Diagnosis USMLE

66) A 13-year-old girl had growth of breast buds at 11 years, followed by the appearance of pubic hair between the ages of 11.5 and 12 years. Which pubertal event is most likely to occur next?

75) A 14-year-old black male comes to the office for the evaluation of pain in his right hip that started several weeks ago. The pain has gradually progressed, and now it limits his daily activities. He has sickle cell disease and was hospitalized three months ago due to a painful crisis that was successfully treated with hydration, oxygen, and analgesics. His temperature is 37.2C (99F), blood pressure is 100/70 mmHg, pulse is 80/min, and respirations are 16/min. Physical examination reveals no local tenderness, but there is restriction of abduction and internal rotation of the hip What is the most likely diagnosis?

77) A 14-year-old boy is brought to the emergency room because of persistent midepigastric pain for two days. The pain is getting no better, yet it is no worse, and radiates to his back. The boy also has had fever, as well as nausea and vomiting that is worse when his temperature rises in the afternoon. On examination, his temperature is 39.2C (102.5F) and there is marked upper abdominal tenderness with guarding. Mild abdominal distention is present with no audible bowel sounds. A complete blood count reveals an elevated leukocyte count and a normal serum amylase. Which of the following is the most likely diagnosis?

91) A 1400-g infant, born at 35 weeks' gestation, is 42 cm in length and a head circumference of 28 cm. One day after birth, she becomes very irritable, tremulous, and inconsolable. Her cry is high-pitched. Her pulse is 174/min. There are no dysmorphic facial features. To which of the following substances was this newborn most likely exposed in utero?

99) A 15-year-old boy is brought to the physician because of a 15-day history of painful swelling of the right knee. The swelling and redness were immediate after hitting his knee on the door, but have not subsided after 15 days of ibuprofen. He states the pain is increasing. He has no other complaints. His temperature is 37.1C (98.9F), blood pressure is 110/75 mm Hg, pulse is 80/min, and respirations are 22/min. Laboratory studies show a normal ESR and elevated serum alkaline phosphatase. Examination shows the skin is warm and non-tender. An x-ray film of the femur and the knee joint shows an osteolytic lesion of the distal femur along with periosteal inflammation. Which of the following is the most likely diagnosis?

116) A 16-year-old boy is persuaded by his older brother to accompany him and his friends on a beer-drinking binge. This is the first such experience for the boy, and it leads to the development of severe colicky left flank pain. When rescued by his parents, he is diaphoretic and doubled up in pain. He relates that he began to urinate frequently and profusely after the third or fourth beer and that the pain seized him shortly thereafter. He is tender to fist percussion over the left costovertebral angle but is afebrile. Which of the following is the most likely diagnosis?

142) A 17-year-old man is brought to the emergency room with confusion and incoordination. He is uncooperative and refuses to provide further history. Physical examination reveals an RR of 30; the vital signs are otherwise normal as is the general physical examination. Laboratory values are as follows: Na: 135 mEq/L, K: 2.7 mEq/L, HCO3: 15 mEq/L, Cl: 110 mEq/L. Arterial blood gases: PO2 92, PCO2 30, pH 7.28 Urine: pH 7.5, glucose—negative, Ca: 9.7 mg/dL, PO4: 4.0 mg/dL. Which of the following is the most likely cause of the acid base disorder?

140) A 17-year-old girl presents to the clinic because she has not yet menstruated and does not have significant breast development. Family history is significant only for some cousins who are color blind. The patient denies ethanol, tobacco, and illicit drug use and sexual activity. Physical examination reveals a normal-appearing girl in no acute distress with minimal breast development and a lack of pubic hair. She is 168 cm (5'6") tall and weighs 61.2 kg (135 lb). Cardiac examination reveals no murmurs, rubs, or gallops, with point of maximal impulse at the left mid-clavicular line between the third and fourth intercostal space. Gynecologic examination reveals a vagina without rugae and a cervix that is easily visualized. There is no discharge. A urine test is negative for β-human chorionic gonadotropin. Which of the following is the most likely diagnosis?

148) A 19-year-old G0 woman presents to her family physician complaining of dysmenorrhea for the past year. She reports severe right-sided pain that coincides with days 1–5 of her menstrual cycle. Her menses occur regularly every 28 days, and she requires three to four pads per day for the first 2 days of her bleeding and one to two pads per day for the remainder. She has never had surgery. She is not sexually active and does not smoke. Her last menstrual period was 1 week ago. Her temperature is 36.7C (98.1F), blood pressure is 121/74 mmHg, heart rate is 80/min, and respiratory rate is 14/min. Physical examination reveals a thin, healthy-appearing young woman. Pelvic examination reveals a normal sized uterus and no cervical motion tenderness. Which of the following is the most likely diagnosis

145) A 17-year-old teenage girl presents to your office with a 10-month history of lower abdominal pain that radiates to the upper thighs and back. The pain is colicky in nature and usually starts a few hours prior to menses, lasting 3-4 days. Menses have occurred at regular 28-day intervals over the past 2 years. She has no inter-menstrual bleeding. She became sexually active 6-months ago and does not use contraception. Physical examination shows healthy external genitalia and well-developed secondary sexual characteristics; the uterus is normal in size and freely mobile. Examination shows no other abnormalities. Which of the following is the most likely cause of her pelvic pathology?

168) A 2-month-old infant is evaluated by a pediatric cardiologist. The infant was noted at birth to have an upper left sternal border ejection murmur. The infant at that time was not cyanotic, but slowly developed cyanosis over the next two months. At the time of the pediatric cardiologist's examination, an ECG showed right axis deviation and right ventricular hypertrophy. A chest x-ray film showed a small heart with a concave main pulmonary artery segment and diminished pulmonary blood flow. Which of the following is the most likely diagnosis?

176) A 2-year-old boy has been vomiting intermittently for 3 weeks and has been irritable, listless, and anorectic. His use of language has regressed to speaking single words. In your evaluation of this patient, which of the following is the most reasonable diagnosis to consider?

192) A 2-year-old child is brought to the physician for a routine visit. He is growing and developing appropriately. He eats a variety of foods including meat, vegetables, and fruits, and drinks 3-4 glasses of whole milk each day. He is starting to put words together into short sentences. His mother has no concerns. Physical examination is unremarkable. Routine laboratory studies show the following: Hemoglobin 9.5 g/dl, RDW 14%, MCV 65 fl, Reticulocyte count 3.0%, Platelet count 212,000/mm3, Leukocyte count 6,500/mm3, TIBC 300 mcg/dl (240-450 mcg/dl), Ferritin 100 ng/ml (7 -140 ng/ml). What is the most likely cause for this child's anemia?

194) A 2-year-old child with minimal cyanosis has an S3 and S4 (a quadruple rhythm), a systolic murmur in the pulmonic area, and a middiastolic murmur along the lower left sternal border. An ECG shows right atrial hypertrophy and a ventricular block pattern in the right chest leads. Which of the following is the most likely diagnosis?

207) A 20-year-old G2P0020 with an LMP 5 days ago presents to the emergency room complaining of a 24-hour history of increasing pelvic pain. This morning she experienced chills and a fever, although she did not take her temperature. She reports no changes in her urine or bowel habits. She has had no nausea or vomiting. She is hungry. She denies any medical problems. Her only surgery was a laparoscopy performed last year for an ectopic pregnancy. She reports regular menses and denies dysmenorrhea. She is currently sexually active. She has a new sexual partner and had sexual intercourse with him just prior to her last menstrual period. She denies a history of any abnormal Pap smears or sexually transmitted diseases. Urine pregnancy test is negative. Urinalysis is completely normal. WBC is 18,000. Temperature is 38.8C (102F). On physical examination, her abdomen is diffusely tender in the lower quadrants with rebound and voluntary guarding. Bowel sounds are present but diminished. Which of the following is the most likely diagnosis?

236) A 21-year-old woman, primigravida, presents at 39 weeks’ gestation in active labor. She is 155 cm tall and weighs 75 kg. Her pregnancy weight gain has been 20 kg. On digital vaginal examination, the fetus is in cephalic presentation at –1 station. Her cervix is 5 cm dilated, 90% effaced, soft, midposition. Onset of regular uterine contractions was 8 hours ago, and she is now experiencing regular contractions every 3 minutes, lasting 45 seconds, which are firm to palpation. Clinical pelvimetry shows her pelvic dimensions as follows: pelvic sidewalls are straight, ischial spines are not prominent, pubic arch is wide, sacrum is hollow, and sacrosciatic notch is well rounded. Based on general bony architecture, the characteristics of this woman’s pelvis identify it as which one of the following common female bony shapes?

237) A 22-month-old boy who recently immigrated from Eastern Europe with his family is brought to your office by his mother who is worried that he seems to tire easily. She describes how he becomes short of breath with even mild physical activity and cannot keep up with his peers during play. The boy is at the 40th percentile for height and 20th percentile for weight. On general examination, there is no clubbing, cyanosis, or peripheral edema, but there is a harsh 3/6 holosystolic murmur over the left lower sternal border and a rumbling diastolic murmur over the cardiac apex. Which of the following is the most likely cause of his symptoms?

270) A 22-year-old woman presents with mouth sores, sore throat, vaginal discharge, fever, and myalgia. She has no other medical problems. She takes oral contraceptive pills. She is in a monogamous relationship and states that her partner occasionally uses barrier contraception. Physical examination reveals a temperature of 38.3 C (101 F), cervical and inguinal lymphadenopathy, exudative pharyngitis, and multiple ulcers on the oral mucosa, the labia, and cervix. The vaginal discharge is profuse, and Gram stain indicates many neutrophils. Which of the following is the most likely diagnosis?

281) A 23-year-old male is brought to the emergency department after a motor vehicle accident. He was an unrestrained driver. He was found unresponsive at the scene of the accident, and was intubated by the paramedics. He has received 2L of normal saline over the last 20 minutes. His blood pressure is 80/40 mmHg, and heart rate is 120/min. He responds to strong vocal and tactile stimuli by opening his eyes. His pupils are equal and reactive to light. His neck veins are distended. There are multiple bruises involving the anterior chest and upper abdomen. His chest x-ray shows a small, left-sided pleural effusion and normal cardiac contours. Which of the following is the most likely diagnosis?

329) A 24-year-old woman, 5 days after delivery of a normal, full-term infant, is brought to the obstetrician because she is so tearful. She states that her mood is quite labile, often changing within minutes. She has trouble sleeping, both falling asleep and awakening early. She notes anhedonia, stating she doesn’t enjoy “much of anything” right now. Which of this patient’s symptoms point preferentially to a postpartum depression?

330) A 24-year-old woman, gravida 2, para 1, at 36 weeks' gestation is brought to the emergency department after passing out. She is drowsy and moaning, complaining of abdominal pain. Her husband accompanies her. He states that she has not experienced any trauma, but that she experienced the sudden onset of severe abdominal pain before she passed out. She has no significant past medical history. Her pregnancy has been uncomplicated thus far. She does not use tobacco, alcohol, or drugs. She takes supplemental vitamins, but no other medications. Her temperature is 36.9 C (98.4F), blood pressure is 90/60 mm of Hg, and pulse is 130/min. Physical examination shows a cold and diaphoretic female. Examination shows a uterus consistent in size with a 36-week gestation; the cervical os is closed and no vaginal bleeding is noted. Which of the following is the most likely diagnosis?

341) A 25-year-old male presents to his physician with dyspnea and fatigue for the last few weeks. He is a non-smoker. He denies any family history of asthma or blood disorders. He does not take any medications. Examination shows pallor, scleral icterus and splenomegaly. Lab tests show the following: Hematocrit 20%, WBC count 10,000/micro-L, Platelet count 180,000/miro-L, Total Bilirubin 7 mg/dl, Direct bilirubin 1.4 mg/dl, BUN 10 mg/dl, Serum creatinine 0.7 mg/dl, Serum LDH 400 U/L (normal value is 80-280 U/L), Serum haptoglobin 160mg/dl (normal value is 30-220 mg/dl ), Reticulocyte count 8 %. Peripheral blood smear shows spherocytes with central pallor. Osmotic fragility and direct Coombs' tests are positive Based on these findings, what is the most likely diagnosis?

351) A 25-year-old white female presents to the clinic with persisting pain in her wrists and ankles for the last 3 months. The pain is 3/10 in intensity, and partially relieved by ibuprofen. She also has a rash on her face. She denies smoking, and drinks alcohol occasionally. Her temperature is 37.3°C (99.2°F), blood pressure is 120/80 mm Hg, pulse is 79/min, and respirations are 18/min. Physical examination reveals swollen joints of the hands and ankle, as well as erythema over the bridge of the nose and the upper cheeks. There is no muscle weakness. Labs show: Hemoglobin 11.0 g/dL, Hematocrit 33%, Platelets 240,000/mm3, WBC 13,600/mm3. Leukocyte distribution:Segmented neutrophils 76%, Lymphocytes 20%, Bands 2%, Monocytes 2%. RF, ANA, and antibodies to double stranded-DNA are positive in high titers. What is the most likely diagnosis?

406) A 27-year-old man is shot point blank with a .22-caliber revolver. The entrance wound is in the anterior chest wall, just to the left of the sternal border, at the level of the 4th intercostal space. There is no exit wound. He is diaphoretic, cold, shivering, and anxious, and is asking for a blanket and a drink of water. His blood pressure is 65/40 mm Hg, and his pulse is 145/min and barely perceptible. He has large, distended veins in his neck and forehead. He is breathing adequately and has bilateral breath sounds. He is neurologically intact. Which of the following is the most likely diagnosis?

414) A 28-month-old female has been living with her mother in a shelter for homeless women and children. She is brought to the Emergency Department in status epilepticus, which is stopped with intravenous lorazepam. She is placed on a cardiac monitor and a wide complex tachycardia is noted. The ventricular tachycardia reverts to sinus tachycardia after defibrillation is performed. Her temperature is 38.5 C (101.3 F), blood pressure is 120/80 mm Hg, pulse is 195, and respirations are 26. Physical examination reveals a lethargic, pale toddler with dilated and reactive pupils, dry mucous membranes, shallow respirations, diaphoresis and brisk deep tendon reflexes. A urine toxicology screen is most likely to detect which of the following substances?

423) A 28-year-old G1 presents to your office at 8 weeks gestation. She has a history of diabetes since the age of 14. She uses insulin and denies any complications related to her diabetes. Which of the following is the most common birth defect associated with diabetes?

465) A 3-week-old infant is being evaluated for hematochezia. His mother states that the infant passed stools j that contain both blood and mucus. There were no complications during her pregnancy, and the infant has been otherwise healthy. On physical examination, his temperature is 37.1 C (98.9 F), pulse is 110/min, and respirations are 18/min. He appears well, and his fontanelle is flat and level. Abdominal examination reveals normal active bowel sounds; his abdomen is nontender to palpation and there is no mass. His diaper contains stool that has bright red blood on it with mucus. Which of the following is the most likely explanation of his hematochezia?

470) A 3-year-old boy is brought to the office by his mother because he has been having painless passage of black stools for the past few days. Otherwise, his bowel habits are normal. He has no other medical problems. He takes no medication. His vital signs are within normal limits. The physical examination is unremarkable. What is the most likely diagnosis of this patient?

512) A 31-year-old accounting student presents with a persistent headache that began approximately 4 months ago. The headache has been gradually increasing in intensity, and is worse in the mornings. Thinking that she might need new glasses, she sought help from her optometrist, who discovered that she has bilateral papilledema and sent her in for medical evaluation. On direct questioning, she admits to repeat vomiting for the past 3 weeks, with no heaving, straining, or preceding nausea. "I would just open my mouth, and the stuff would hit the wall," she explains. She denies any other neurological symptoms. Which of the following is the most likely diagnosis?

542) A 32-year-old male presents to your office complaining of daytime sleepiness and frequent night-time awakenings. He says that his sleep gets disrupted by a choking sensation, sometimes accompanied by cough and dyspnea. After such episodes he typically has trouble falling back to sleep. The patient notes that his symptoms are somewhat improved when he sleeps with multiple pillows. Physical examination is unremarkable except for a BMI of 29 Kg/m2. What is the most likely diagnosis?

577) A 33-year-old white man with a 9-year-history of progressive-relapsing multiple sclerosis is brought to the emergency department (ED) due to a severe flare-up. He has had several attacks before, and has recovered every time with some residual damage. The last physical examination in his medical records revealed cerebellar symptomatology, a visual defect, and central hemiparesis on the right side. MRI showed multiple, bright, signal abnormalities in the white matter supratentorially on the left side, in the cerebellum, and the left optic nerve. CSF examination revealed an increased synthesis of oligoclonal bands. In the ED, the physical examination reveals paraplegia, bladder and fecal incontinency, and absent sensation from the nipples down. What is the most likely location of this patient's new plaque?

593) A 34-year-old man comes to the physician after being involved in a street fight. He has a painful and swollen left arm. Neurovascular examination shows no abnormalities. An x-ray film of the arm shows a fracture of the midshaft of the humerus. Closed reduction of the facture is done and the arm is kept in a hanging cast. One hour later he has numbness of the left wrist and marked limitation of extension at the wrist. Which of the following is the most likely diagnosis?

666) A 36-year-old woman, gravida 3, para 2, comes to the physician for a prenatal checkup. According to her last menstrual period and an ultrasonography performed at 16 weeks gestation, she is at 30 weeks gestation. She missed two antenatal appointments. She does not use tobacco, alcohol, or drugs. Examination shows a fundal height of 26 cm (9.8 in). Fetal heart tones are heard by Doppler. Repeat ultrasound shows a fetal biparietal diameter consistent with 30 weeks and an abdominal circumference below the 10th percentile. Which of the following could most likely be responsible for the observed fetal findings?

728) A 4-year-old, apparently healthy child is examined by a pediatrician. The pediatrician hears a loud systolic ejection murmur with a prominent systolic ejection click. He also hears a soft, early diastolic murmur. Both murmurs are heard best at the upper right sternal border. ECG shows left ventricular hypertrophy. Which of the following is the most likely diagnosis?

755) A 42-year-old man has had a rocky course for the 3 days following a bowel resection for intestinal perforation due to inflammatory bowel disease. His CVP had been 12 to 14 but is now 6, in the face of diminished blood pressure and oliguria. Which of the following is the most likely etiology of his hypotension?

758) A 42-year-old man presents to the emergency department complaining of two weeks of weakness, low-grade fevers, and exertional shortness of breath. He also notes fingertip pain and urine that has been dark and cloudy recently. On physical examination, several of his proximal inter phalangeal joints are swollen. Which of the following diagnoses is most consistent with his presentation?

787) A 44-year-old male is found unresponsive and hypotensive at the scene of a high-speed motor vehicle accident. He is intubated and immediately rushed to the emergency department. The passenger in his car is pronounced dead at the scene. Physical examination in the ED shows large bruises over the entire chest wall and collapsed neck veins bilaterally. Lung exam reveals decreased breath sounds on the left side. Chest x-ray shows a large left hemothorax and a widened, rightward deviating mediastinum. The most likely diagnosis is?

788) A 44-year-old man complains of vague right upper abdominal discomfort that he has had for about 1 month. He describes no other symptoms, and, except for enucleation of one eye at age 21 "for a tumor," he has been in excellent health all his life. He exercises regularly and neither smoke nor drinks. The only findings on physical examination include the artificial eye and a tender, enlarged, and nodular liver. CT scan of the upper abdomen demonstrates multiple masses within the liver. Which of the following will most likely be found on biopsy of these masses?

800) A 45-year-old male presents to his physician with persistent nausea and vomiting of partially digested food for the past month. He has also lost 5 lbs of weight during this period of time. His appetite is good but he feels full after a few bites. His past medical history is significant for a one-year history of type 2 diabetes and a suicide attempt 6 months ago in which he ingested acid. He drinks alcohol and smokes one pack of cigarettes daily. His temperature is 36.80C (98.20 F), blood pressure is 110/65 mm Hg, pulse is 110/min, and respirations are 16/min. Mucous membranes are dry. Examination shows succussion splash on the epigastrium. Which of the following is the most likely diagnosis?

813) A 45-year-old nurse practitioner presents to the emergency department due to painful abdominal cramps and watery diarrhea. She has about 10 to 20 bowel movements a day. She also has nocturnal bowel movements. She has had multiple hospitalizations in the past for similar problems without a definite diagnosis. A lower GI endoscopy during a previous hospitalization showed dark brown discoloration of the colon with lymph follicles shining through as pale patches. Which of the following is the most likely diagnosis?

826) A 45-year-old woman presents with hypertension, development of facial hair, and a 7-cm suprarenal mass. Which of the following is the most likely diagnosis?

859) A 5-day-old male premature infant in the NICU develops a decreased level of consciousness, hypotonia and decreased spontaneous movements. He was delivered vaginally at 32 weeks of gestation, and his birth weight was 1800g. Examination reveals a lethargic infant with a weak and high-pitched cry, prominent scalp veins, tense fontanels, and eyes directed downward, poor suckling, hypotonia. CT scan reveals dilation of the entire ventricular system, with distinct enlargement of the subarachnoid space over the cerebral cortex. What is the most likely cause of the patient's condition?

855) A 49-year-old G4P4 presents to your office complaining of a 2-month history of leakage of urine every time she exercises. She has had to limit her physical activities because of the loss of urine. She has had burning with urination and some blood in her urine for the past few days. Which of the following is the best next step in the evaluation and management of this patient?

1445) An 81-year-old woman presents to your office complaining that her uterus fell out 2 months ago. She has multiple medical problems, including chronic hypertension, congestive heart failure, and osteoporosis. She is limited to sitting in a wheelchair because of her health problems. Her fallen uterus causes significant pain. On physical examination, the patient is frail and requires assistance with getting on the examination table. She has complete procidentia of the uterus. Which of the following is the most appropriate next step in the management of this patient?

910) A 51-year-old man is undergoing abdominal surgery and becomes hypotensive while under general anesthesia. The patient had been doing well during most of the procedure but now has a blood pressure of 80/40 mm Hg. His past medical history is significant for coronary artery disease and diabetes mellitus. A pulmonary artery catheter placed prior to the procedure gives the following data: Central venous pressure 10 mmHg, Pulmonary artery pressure 60/30 mmHg, Pulmonary capillary occlusion 24 mm Hgpressure Cardiac output 2.3 L/min. Which of the following is the most likely diagnosis?

912) A 51-year-old woman is diagnosed with invasive cervical carcinoma by cone biopsy. Pelvic examination and rectal-vaginal examination reveal the parametrium to be free of disease, but the upper portion of the vagina is involved with tumor. Intravenous pyelography (IVP) and sigmoidoscopy are negative, but a computed tomography (CT) scan of the abdomen and pelvis shows grossly enlarged pelvic and periaortic nodes. This patient is classified at which of the following stages?

919) A 52-year-old man has suffered with chronic diarrhea for several years, but has refused to see a doctor. He finally comes because he is having trouble driving at night, because of difficulty seeing. Physical examination reveals a slender, pale, unwell-looking man. He has a microcytic anemia, low calcium, and albumin levels. Which of the following is the most likely cause for his diarrhea?

923) A 52-year-old man presents to your office after passing a black stool. He also describes occasional abdominal discomfort and nausea but denies hematemesis. He says that food seems to help his abdominal pain, so he eats frequently during the day and keeps some snacks on his night stand. As a consequence, he has gained 5 pounds over the last year. He admits that his diet is lacking in vegetables and fruit. He drinks one to two cans of beer nightly, but does not smoke or use illicit drugs. He says that his father died of colon cancer and his mother died from a stroke. Physical examination reveals a right-sided carotid bruit. The fecal occult blood test is positive. Which of the following is the most likely cause of his condition?

938) A 53-year-old woman presents with weight loss and a persistent rash to her lower abdomen and perineum. She is diagnosed with necrolytic migrating erythema and additional workup demonstrates diabetes mellitus, anemia and a large mass in the tail of the pancreas. Which of the following is the most likely diagnosis?

945) A 54-year-old male comes to the physician's office because of chronic cough and recent bloody sputum. He used to smoke 2 packs of cigarettes daily for 22 years, but he quit last month. His other symptoms are weight loss, anorexia, constipation, increased thirst, and easy fatigability. He thinks that he is depressed because his wife died 4 months ago and "life never felt the same after that." On examination, he is a slim man who appears pale. His vital signs are stable, although he appears a little irritable and short of breath. Laboratory and radiologic studies reveal: Sodium 144 mEq/dL, Potassium 4.3 mEq/dL, Chloride 98 mEq/dL, Bicarbonate 21 mEq/dL, Calcium 11.5 mg/dl, BUN 28 mg/dl, Creatinine 0.8 mg/dl. Chest x-ray hilar mass in the left lung. Biopsy of the mass would most likely reveal?

953) A 54-year-old man is brought to the emergency department 1 0 minutes after being involved in a motor vehicle collision. On arrival, he is breathing spontaneously, is non-cyanotic and has no signs of external injury. His temperature is 37C (98.6F), blood pressure is 104/50 mm Hg, pulse is 122/min and respirations are 16/min. Examination shows bilateral round and reactive pupils of 4 mm. He is making some incomprehensible sounds. He responds to his name by opening his eyes and on applying supraorbital pressure he extends his left extremity and grasps your hand with his right hand. What is the Glasgow coma scale (GCS) in this patient?

998) A 56-year-old female is admitted with a diagnosis of chronic renal failure from systemic lupus erythematosus and non-steroidal anti-inflammatory drug use. She has a history of recurrent kidney stones. Laboratory studies show the following: Serum calcium 10.6 mg/dL, Serum albumin 3.9 g/L, PTH 140 pg/mL, Serum phosphorus 3.0 mg/dL. Her baseline serum creatinine level ranges from 1.6 to 1.8 mg/dL. Her bone mineral density is measured by DXA scan, revealing a T score of-2.5 at the lumbar spine, which is consistent with osteoporosis. What is the most likely cause of this patient's hypercalcemia?

1068) A 60-year-old male is admitted to the hospital because of right lower lobe pneumonia. His medical history is significant for hypertension, diabetes mellitus, severe degenerative disease of the spine, and longstanding lower back pain. He is a chronic smoker with a 40-pack year smoking history. During his hospitalization, the laboratory report shows decreased serum calcium levels and increased phosphate levels. Further evaluation reveals increased serum intact parathyroid hormone levels. Which of the following medical conditions is most likely responsible for this patient's abnormal lab findings?

1087) A 62-year-old Caucasian woman complains of difficulty remembering important dates and appointments. She also describes poor concentration, daytime sleepiness and easy fatigability. She is concerned about her forgetfulness because her mother suffered from recurrent strokes and had severe memory loss. Her father died of chronic leukemia. Her daughter's recent job loss has caused her a lot of stress. She does not smoke or consume alcohol. Her appetite is decreased but she has gained 4 pounds over the last three months. She visited an otolaryngologist for hoarseness of recent onset. She takes over- the-counter laxatives for constipation and occasional aspirin for knee pain. She denies any other medication use. Which of the following is the most likely diagnosis in this patient?

1093) A 62-year-old man presents to his primary care physician's office with progressive exertional dyspnea. His past medical history is significant for hypertension treated with hydrochlorothiazide and diabetes mellitus treated with metformin. He was an industrial worker for 30 years and retired one year ago. He smokes one pack of cigarettes per day and consumes alcohol occasionally. His blood pressure is 150/100 mmHg and his heart rate is 80/min. His BMI is 31 kg/m2. Chest x-ray reveals pleural calcifications. Pulmonary function studies show the following: FEV1 70% of predicted, FVC 65% of predicted, Residual volume 70% of predicted, DLCO decreased. Which of the following is the most likely cause of this patient's symptoms?

1016) A 56-year-old woman presents for evaluation of a murmur suggestive of mitral stenosis and is noted on echocardiography to have a lesion attached to the fossa ovalis of the left atrial septum. The mass is causing obstruction of the mitral valve. Which of the following is the most likely diagnosis?

1049) A 6-year-old boy is brought to the physician by his mother with complaints of "inattentivity." His school teacher frequently complains about him, saying that he, "cannot sit still and just does not listen." He rarely completes his classroom assignments in time. When asked to run errands at home, he appears not to listen and continues to do whatever he is engaged in. He makes poor eye contact and has limited language skills compared to his peers. He usually prefers to play by himself. Which of these is the most likely diagnosis in this case?

1108) A 63-year-old man alcoholic with a 50-pack-year history of smoking presents to the emergency room with fatigue and confusion. Physical examination reveals a blood pressure of 110/70 mm Hg with no orthostatic change. Heart, lung, and abdominal examinations are normal and there is no pedal edema. Laboratory data are as follows: Na: 110 mEq/L, K: 3.7 mEq/L, Cl: 82 mEq/L, HCO3: 20 mEq/L, Glucose : 100 mg/dL, BUN : 5 mg/dL, Creatinine: 0.7 mg/dL Urinalysis: normal Specific gravity: 1.016. Which of the following is the most likely diagnosis?

1130) A 64-year-old man presents to the ER with back pain and frequent falls. He also describes difficulty initiating urination. The symptoms started one week ago and have progressed gradually. He was diagnosed with prostate cancer one year ago and treated with radiation therapy. Physical examination reveals weakness of knee and hip extension that is more pronounced on the right. Knee and ankle reflexes are absent bilaterally. Babinski sign is negative. Perianal skin is insensitive to touch but sensation in the anterolateral thigh is preserved. Which of the following is the most likely lesion location in this patient?

1131) A 64-year-old man presents with weight gain, shortness of breath, easy bruising, and leg swelling. On examination, his blood pressure is 140/80 mm Hg, pulse 100/min, JVP 4 cm, heart sounds normal, and lungs are clear. There is a 3+ pedal and some periorbital edema. Investigations include a normal chest x-ray (CXR), electrocardiogram (ECG) with low voltages, anemia, high urea and creatinine, and 4 g/day of protein in the urine. A renal biopsy, which shows nodular deposits that have an apple-green birefringence under polarized light when stained with Congo red. Which of the following is the most likely diagnosis?

1166) A 65-year-old man with chronic obstructive pulmonary disease, chronic atrial fibrillation, hypertension, and diabetes mellitus presents with a three-day history of shortness of breath. His condition began with runny nose, itchy eyes, and sore throat, but his symptoms progressed to productive cough, wheeze, and dyspnea. Physical examination reveals a mildly overweight man in moderate respiratory distress. His blood pressure is 150/90 mmHg and his heart rate is 110/min and irregular. On chest auscultation, expirations are prolonged and there are bilateral wheezes. You administer bronchodilators, facial mask oxygen, and lorazepam for agitation. Thirty minutes later, he is lethargic and confused. While you discuss the case with your attending, the patient experiences a generalized tonicclonic seizure. Which of the following most likely underlies his neurologic symptoms?

1190) A 67-year-old Asian male comes to the clinic for the first time. He walks very slowly as he enters the room. His chief complaint is "extreme forgetfulness" for the past 6 months. He tearfully shares that he has been "losing sleep." He used to be a very "bright and sharp" person, but is now unable to focus on his daily activities and feels "really extremely low and useless." His past medical history is significant for hypertension, hypercholesterolemia, diabetes, benign prostatic hyperplasia, and TIA. His family history is insignificant, except for Alzheimer's dementia in his father. He does not smoke, and drinks wine only occasionally. He has been living alone for the last 6 months, after his son moved out. His physical exam is normal, except for markedly slow movements. A CT scan of the head is normal. Which of the following is the most likely diagnosis?

1199) A 67-year-old woman comes to her physician because she is feeling tired, all the time. She thinks that it is due to multiple surgeries she had over the past several years. She had two caesarian sections at the age of 22 and 26. She also had a thyroid surgery for Graves’s disease, 30 years ago. 12 years ago she was diagnosed with colon cancer and had undergone left hemicolectomy. She denies smoking or alcohol use. Her vitals are Temperature 36.7°C (98.2°F); BP 138/86 mm Hg; PR 77/min; RR 12/min. She looks markedly pale and has weakness in all four extremities. There is some sensory loss in lower limbs. The test for occult blood was negative. Labs came back as: Sodium 144 mEq/L, Potassium 4.2 mEq/L, Bicarbonate 24mEq/L, Blood urea nitrogen 18mg/dl, Creatinine 1.0 mg/dl, Glucose 82 mg/dl, WBC 8,600/cmm, Hemoglobin 7.9, Hematocrit 25%, Platelets 176,000/cmm. The physician decides to further investigate anemia and order RBC indices and peripheral blood smear. The results are: MCV 120 fl, MCH 36 pg, MCHC 28%, Reticulocyte count 04%. Peripheral smear showed anisocytosis, poikilocytosis, 4+ macrocytes, polychromatophilia and basophilic stippling. A whole new bunch of tests are ordered and the following report is seen on the computer. Vitamin B12 106 pg/ml (N=210-911 pg/ml), Serum Folate 16.4 ng/ml (N=2.8-17.8 ng/ml), Serum Bilirubin 1.8 mg/dl, Serum LDH 2500 U/L. Gastric analysis demonstrated an absence of hydrochloric acid. What is the most probable cause of her anemia?

1239) A 70-year-old Caucasian male is brought to the emergency department due to a sudden onset of right-sided weakness and urinary incontinence about ten hours ago. His past medical history is significant for type 2 diabetes for the last 20 years and hypertension for the last 28 years. On examination, there is 3/5 power in the right upper extremity and 1/5 power in the right lower extremity. Babinski's sign is positive on the right side. The sensations are decreased on the right side of the body, more so in the right lower limb than the right upper limb. Which of the following is the most likely diagnosis?

1255) A 72-year-old Caucasian man presents to your office complaining of severe fatigue. He says that five months ago he was able to climb four flights of stairs without shortness of breath, but now he has to rest after two. His appetite has decreased, but he denies any abdominal discomfort or black stool. Physical examination reveals firm, enlarged cervical and supraclavicular lymph nodes. A soft I/VI grade systolic murmur is heard along the left sternal border. Abdomen is soft and non-tender. His liver span is 10 cm and the spleen is palpated 4 cm below the left costal margin. His blood hemoglobin level is 7.5 mg/dl. Which of the following is the most likely cause of this patient's anemia?

1265) A 72-year-old woman complains of difficulty "finding the right word" when she is speaking. Her daughter notes that she also frequently complains that her neighbor is stealing her newspapers when this is not the case in actuality. Recently, the patient has been having difficulty balancing her check book as well. On physical examination, her blood pressure is 160/100 mmHg and her heart rate is 90/min. The exam is otherwise unremarkable. Over the course of the next three years, the patient develops a severe memory deficit, and suffers from poor sleep, slowness of movement, shuffling gait and urinary incontinence. Which of the following is the most likely diagnosis?

1276) A 74-year-old man presents to his primary care physician complaining of dyspnea and cough with blood-tinged sputum for the past several weeks. He has diabetes and elevated cholesterol. Medications include a sulfonylurea and a statin. The patient has a 50-pack-year smoking history and a family history of hypertension. His vital signs are within normal limits. Physical examination reveals abdominal striae and moon facies, along with a truncal fat distribution. X-ray of the chest reveals a single central nodule, and follow-up CT again demonstrates the nodule and multiple solid hepatic masses. Which of the following is the most likely diagnosis?

1290) A 75-year-old patient presents to the ER after a syncopal episode. He is again alert and in retrospect describes occasional substernal chest pressure and shortness of breath on exertion. His blood pressure is 110/80 mmHg and lungs have a few bibasilar rales. Which auscultatory finding would best explain his findings?

1307) A 78-year-old man comes to the physician because of a bloody urethral discharge for 3 days. He has had increasing frequency of urination and hesitancy for the past 2 years, but these symptoms have never been severe enough to require medical attention. Digital rectal examination reveals a slightly enlarged and firm prostate. Expressed prostatic secretions are negative for bacteria and leukocytes. Collection of clean-catch urine in separate aliquots reveals initial hematuria, with blood present in the first 5 mL. Which of the following is the most likely diagnosis?

1341) A full-term neonate presents with hypotonia, lethargy and poor feeding over the past three hours. The pregnancy was uneventful, but during delivery, the neonate presented with shoulder dystocia and subsequently obtained a fracture of the clavicle. His Apgar scores are 7 and 8 at one and five minutes, respectively. His birth weight is 4000g. His vital signs are normal. Physical examination reveals an enlarged tongue, mild microcephaly, prominent occiput, prominent eyes and omphalocele. Abdominal palpation reveals an enlarged liver and kidneys. The initial work-up reveals hypoglycemia and hyperinsulinemia. What is the most likely diagnosis?

1347) A healthy 59-year-old woman with no history of urinary incontinence undergoes vaginal hysterectomy and anteroposterior repair for uterine prolapse, large cystocele, and rectocele. Two weeks postoperatively, she presents to your office with a new complaint of intermittent leakage of urine. What is the most likely cause of this complaint following her surgery?

1356) A middle-aged, divorced mother brings her 19-year -old daughter in for an evaluation. She says that her daughter has "a serious problem." The woman is concerned because her daughter always keeps to herself, does not date, has no close friends, and refuses to participate in activities popular with women of her age. The daughter is extremely fascinated by witchcraft, spending countless hours in her room gazing into a crystal ball and muttering under her breath. When confronted about her behavior, she says, "I have some supernatural powers that I am not willing to discuss." She attends college regularly and earns good grades. Which one of the following is the most likely diagnosis?

1357) A middle-aged, divorced woman brings her 18-year-old daughter to the physician with the complaint that her daughter "seems abnormal." She is concerned because her daughter has no close friends, does not date, and shows no interest in the activities that are popular with young adults. The girl prefers solitude and keeps to her room for most of the day. When she does go out, she hikes in the woods alone for hours at a time. She attends a local university where she studies engineering and performs well academically. During the office visit, the daughter avoids eye contact. In response to questioning about her reasons for being aloof, she replies, "I just don't enjoy being in the company of others. People do not interest me much and I would rather keep to myself." Her thought process appears devoid of delusions or hallucinations. Which of the following personality disorders is demonstrated by her behavior?

1364) A mother brings her 9-month-old daughter to the pediatrician with complaints of a rash. The mother states that the infant had a high fever [temperature up to 40.0 C (104 F)] for 3 days prior to developing the rash, but is now afebrile. The mother also says that the infant has had a runny nose and a slight cough for the past 3 days. On examination, there is a fine macular rash on the infant's trunk and neck. The examination is otherwise within normal limits, and the infant is playful and smiling. Which of the following is the most likely diagnosis?

1369) A neonate develops severe cyanosis that begins within minutes of birth. Blood drawn one hour after birth shows metabolic acidosis with respiratory acidosis. A chest x-ray film shows a narrow base to the great vessels and the heart resembles an egg on its side. ECG is normal. Which of the following is the most likely diagnosis?

1376) A newborn infant born from a mother with polyhydramnios presents with excessive salivation along with coughing and choking with the first oral feeding. An xray of the abdomen shows gas in stomach and a nasogastric tube coiled in the esophagus. Which of the following is the most likely diagnosis?

1383) A patient develops a fever and tachycardia during a blood transfusion after a redo coronary artery bypass procedure. The nurse subsequently discovers that there was a mix-up in the cross-match because of a labeling error. Which of the following is diagnostic in a patient with an immediate hemolytic reaction secondary to a blood transfusion?

1397) A premature neonate develops respiratory distress syndrome several hours after birth. The infant is placed on a respirator and given other appropriate care. However, when the infant reaches a corrected gestational age of 36 weeks, he does not tolerate weaning from the ventilator. A chest x-ray film demonstrates alternating areas of hyperaeration and pulmonary scarring, resulting in parenchymal streaks and hyperexpanded areas. Which of the following is the most likely diagnosis?

1416) A previously healthy full-term infant has several episodes of duskiness and apnea during the second day of life. Diagnostic considerations should include which of the following?

1433) A vomiting infant is brought to the emergency room. The blood work results reveal a normal blood count, but a hyponatremic, hypochloremic, metabolic alkalosis. Which of the following would be consistent with these findings?

1443) After a grand mal seizure, a 32-year-old epileptic woman notices pain in her right shoulder, and she cannot move it. She goes to a minor emergency clinic, where she has a limited physical examination and anteroposterior (AP) x-ray films of her shoulder. The films are read as negative, and she is diagnosed as having a sprain and given pain medication. The next day, she still has the same pain and is unable to move her arm. She comes to the emergency department holding her arm close to her body, with her hand resting on her anterior chest wall. Which of the following is the most likely diagnosis?

1447) Among the conditions that cause edema of the eyelids is orbital cellulitis. This is a serious infection that must be recognized early and treated aggressively if complications are to be avoided. Which of the following features is useful in differentiating orbital cellulitis from periorbital (preseptal) cellulitis?

1462) An 18-year-old male college student is seen in the student health clinic for urinary frequency, dysuria, and urethral discharge. Which of the following is likely to explain his condition?

1494) An 80-year-old female is brought to your office, by her son, because of severe fatigue. She lives alone and is suffering from severe degenerative joint disease, which puts her in a house arrest-type state. Her son usually helps with getting grocery. Her only other medical problem is hypertension. She takes hydrochlorothiazide and acetaminophen. Her vitals are stable. On examination, she has pallor, and evidence of severe degenerative joint disease. Which of the following is the most likely cause of pallor in this patient?

1509) An 88-year-old male complains of severe right calf pain several hours after undergoing a right femoral artery embolectomy. He also complains of a burning sensation in his posterior right leg. He has a long history of atrial fibrillation and hypertension. His past medical history also includes stroke, bleeding duodenal ulcer, diabetes mellitus and diabetic nephropathy. On physical examination, his blood pressure is 160/70 mm Hg and his heart rate is 100 per minute and irregular. His right calf is swollen, tense and exquisitely tender; the pain is worsened by passive extension of the right knee. Dorsalis pedis and posterior tibial pulses are palpable in the bilateral lower extremities. Which of the following is the most likely cause of this patient's symptoms?

1522) An irritable 6-year-old child has a somewhat unsteady but nonspecific gait. Physical examination reveals a very mild left facial weakness, brisk stretch reflexes in all four extremities, bilateral extensor plantar responses (Babinski reflex), and mild hypertonicity of the left upper and lower extremities; there is no muscular weakness. Which of the following is the most likely diagnosis?

1526) An otherwise healthy 7-year-old child is brought to you to be evaluated because he is the shortest child in his class. Careful measurements of his upper and lower body segments demonstrate normal body proportions for his age. Which of the following disorders of growth should remain in your differential?

1527) An out-of-shape, recently divorced, 42-year-old man is trying to impress a young woman by challenging her to a game of tennis. In the middle of the game, a loud "pop" (like a gunshot) is heard, and the man falls to the ground clutching his ankle. He limps off the court with pain and swelling in the back of the lower leg. Although he can still weakly plantar-flex his foot, he seeks medical help the next day because of persistent pain, swelling, and limping. He can put weight on that foot with no exacerbation of the pain, but the motion of taking a step is painful. Which of the following would be the most likely finding on physical examination?

1566) Starting over 9 months ago, a 39-year-old multiparous woman complains about having increasing heavy vaginal bleeding and pain with her menstrual periods. Two years ago, after workup for an abnormal Pap smear reported a low-grade squamous intraepithelial lesion (LSIL), she underwent cryotherapy for biopsy-confirmed cervical intraepithelial neoplasia grade I (CIN 1). Subsequent follow-up Pap smears have been negative. Her present pelvic examination is unremarkable except for a diffusely enlarged, globular, soft, tender uterus. Results of a qualitative urine -human chorionic gonadotropin (-hCG) test are negative. Which of the following is the most likely diagnosis?

1595) The police bring a 14-year-old boy to the clinic after he was found setting fire to the neighbor's house. He has been previously arrested and warned by the cops twice. The first time was 15 months ago for stealing his neighbor's motorcycle. The second occasion was 6 months ago for a fight with his peers on the roadside. His parents arrive and tell you that he has been behaving this way for the past 3 years, and often argues at home. He steals money from them and tries to hurt the pets. Although they have not seen him using any drugs, they suspect that his behavior could be due to drugs. What is the most likely diagnosis?

1609) While making rounds in the newborn nursery, the nurses ask you to examine a 2-day-old infant who is not feeding well. The nurse reports that the infant is irritable, is not sleeping well, and has had several episodes of vomiting and loose stools today. A review of the maternal history reveals that she had poor prenatal care and the pregnancy was complicated by intrauterine growth restriction. On examination, the infant is diaphoretic and has a high-pitched cry. The infant is also noted to have occasional sneezing and is mildly tachypneic. No dysmorphic features are noted and the remainder of the examination is unremarkable. This infant's symptoms are most likely caused by prenatal exposure to which of the following?

1626) You find a discrete, whitish polyp that extends through the tympanic membrane in a child with a history of recurrent otitis media. This most likely represents which of the following?

1354) A married couple brings their 2-week-old infant to the office for the evaluation of lethargy, poor feeding and hypotonia. The infant was "fine" until yesterday, when he started to present with these symptoms. The mother's medical history is unremarkable, and her pregnancy was uneventful. On examination, hypotonia, poor reflexes and bulging fontanel are noted. There are no focal neurological signs. He is hypotensive and tachycardiac. His temperature is 39.4 C (103F). Initial investigation reveals a WBC count of 16,000/mm3 with 18% bands. What is the most likely diagnosis?

714) A 4-year-old boy presents with severe pains in both of his legs. On physical examination, his temperature is 37.7 C (99.8 F), blood pressure is 108/68 mm Hg, pulse is 96/min, and respirations are 17/min. He is noted to have marked pallor on his lips and palpebral conjunctiva. Numerous purpura and petechiae are noted on his skin. His spleen is palpable 3 cm below his left costal margin. Laboratory evaluation reveals a white blood cell count of 1600/mm3; hemoglobin, 6.1 g/dL; and platelets, 36,000/mm3. Which of the following diagnoses is most consistent with these findings?

704) A 4-month-old male infant is brought to the office by his parents due to progressive lethargy, poor feeding, fatigue and increasing pallor for the past four weeks. His antenatal and birth histories are unremarkable. His diet consists mainly of breast milk. His immunizations are up-to-date. His mother's blood type is 0 +. Physical examination reveals a webbed neck, cleft lip, shielded chest, triphalangeal thumbs, and pale mucous membranes and conjunctivae. Cardiac auscultation reveals mild tachycardia and a systolic ejection murmur over the left upper sternal border. The initial investigations reveal the following: Hb 8 g/dl, Ht 26%, WBCs 7,000/mm3, Platelets 300,000 /mm3, Reticulocytes 04%, MCV 104 fl, Blood type A -, Bilirubin direct 0.1 mg/dl, Bilirubin total 1.0 mg/dl. What is the most likely diagnosis?

1052) A 6-year-old boy presents in clinic for a routine visit. Examination reveals coarse, dark pubic hair, an enlarged penis and testes, and acne of the face and upper back. His mother notes that he has a body odor similar to that of her teenage son after playing sports. The child is in file 99th percentile of height for his age group. Which of the following is the most likely diagnosis?

7) A 1-day-old male infant has bilious vomiting after every feeding. He hasn't passed any stools yet. He had no prenatal care, and was delivered vaginally at term. He weighs 3kg (6.61b), and his APGAR scores were 6 and 7 at 1 min and 5 min, respectively. On examination, the neonate is hypotonic, he has a flat facial profile, short ears with downfolding ear lobes, a single palmar crease, and a depressed fontanel. There is abdominal distention which is most prominent in the upper abdomen. His abdominal x-rays show gastric and duodenal gas distension with no air distally. What other anomaly can also be expected in this infant?

162) A 2 and a half-year-old child is brought to the office for the evaluation of easy bruising, nosebleeds, and decreased activity over the past week. He had an upper respiratory infection that was treated with an antibiotic 2 weeks ago. On examination, he is well-developed, seems well-nourished, anicteric, and pale. Pertinent findings include some small palpable posterior cervical lymph nodes, sinus tachycardia, a grade I/VI systolic ejection murmur, ecchymoses on his left shoulder and both lower extremities, and petechiae over his extremities and groin. There is no hepatosplenomegaly. The laboratory findings are as follows: Hemoglobin 7.9 g/dl, Hematocrit 24%, Platelet count 12, 000/mm3, WBC 3,000/mm3, Reticulocyte count 0.5%. A bone marrow biopsy reveal a markedly hypocellular marrow with decreased megakaryocytes and precursors of the erythroid and myeloid cell lines. What is the most likely diagnosis?

995) A 55-year-old, HIV-positive man has a fungating mass growing out of the anus. He can feel it when he wipes himself after having a bowel movement, but it is not painful. For the past 6 months, he has noticed blood on the toilet paper, and from time to time there has also been blood coating the outside of the stools. He has lost weight, and he looks emaciated and ill. On physical examination, the mass is easily visible. It measures 3.5 cm in diameter, is fixed to surrounding tissues, and appears to grow out of the anal canal. He also has rock-hard, enlarged lymph nodes on both groins, some of them as large as 2 cm in diameter. Which of the following is the most likely diagnosis?

1442) Acute renal failure occurs following aortic angiography in a 72-year-old man. His weight has been rising, his lungs show rales at both bases, and he is dyspneic. His fractional excretion of sodium is greater than 1. He has eosinophilia on his peripheral smear, an elevated erythrocyte sedimentation rate, and proteinuria with microscopic hematuria. Which of the following is the most likely cause of his renal failure?

502) A 30-year-old previously healthy man presents with refractory hypertension on four medications. Urinalysis is positive for metanephrines. He was adopted as an infant and therefore does not know his family history. Which of the following inherited syndromes is not associated with this disease?

500) A 30-year-old man with a history of Crohn disease develops an enterocutaneous fistula and is placed on total parenteral nutrition through a right subclavian central venous catheter. After 5 days, the patient develops a fever and leukocytosis; CT scan of the abdomen reveals no intra-abdominal abscess. The subclavian catheter insertion site is inspected and noted to be erythematous and painful. Blood cultures are positive. Which of the following organisms is the most likely cause of his fever?

466) A 3-week-old infant is brought in because of 2 days of protracted bilious vomiting. He looks acutely ill, and plain x-rays show two large air fluid levels in the upper abdomen, the larger one on the left side and a smaller one on the right side. The radiologist describes the finding as a "double bubble sign." He also reports that there is intraluminal gas distal to those two air fluid levels, but that it is sparse and does not outline distended loops. Which of the following is the most likely tentative clinical diagnosis?

589) A 34-year-old male is involved in a high-speed highway motor vehicle collision. He is intubated by rescue workers at the accident scene. In the emergency department, the patient has decreased breath sounds on the right side, normal breath sounds on the left, and hypotension. A right-sided chest tube is placed. Physical examination reveals multiple bruises over the entire chest wall as well as subcutaneous emphysema. A few hours later, his chest x-ray shows an accumulation of air in the pleural space as well as pneumomediastinum. Which of the following is the most likely diagnosis?

1094) A 62-year-old man presents with a 3-month history of an enlarged lymph node in the left neck. He is a long-time smoker of cigarettes and denies fevers, night sweats, fatigue, or cough. On physical examination there is a 1.5 cm hard, fixed mass below the angle of the mandible in the left neck. Which of the following is the most likely cause of an enlarged lymph node in the neck?

369) A 26-year-old man comes to the physician with the chief complaint of a depressed mood for the past 5 weeks. He has been feeling down, with decreased concentration, energy, and interest in his usual hobbies. Six weeks prior to this office visit, he had been to the emergency room for an acute asthma attack and was started on prednisone. Which of the following is the most likely diagnosis?

1280) A 74-year-old woman develops acute sepsis from pneumonia and is admitted to the intensive care unit because of hypotension. She is started on antibiotics, and her blood pressure is supported with intravenous normal saline. Despite this she remains oliguric and develops ARF. Her urinalysis has heme-granular casts and the urine sodium is 56 mEq/L. Which of the following is the most likely cause of her ARF?

843) A 47-year-old woman comes to the office and complains of burning abdominal pain which has been present for the past 3 months, is grade 6/10 in severity, continuous, and relieved by taking antacids. She also complains of some constipation. Her father has a history of "ulcers in his belly." She works as a floor secretary in a surgical ward, and is not happy with her new boss. She denies any weight loss or decreased appetite. Her temperature is 37.1°C (98.8°F), blood pressure is 130/85 mm Hg, heart rate is 78/min, and respirations are 14/min. She is awake, alert, and oriented. The abdominal examination reveals normoactive bowel sounds and tenderness in the epigastric region, but no palpable mass. Her stools are occult blood positive. ECG reveals increased PR and shortened QT intervals. The laboratory results reveal the following: Sodium 137 mEq/dL, Potassium 4.2 mEq/dL, Chloride 101 mEq/dL, Bicarbonate 27 mEq/dL, Calcium 12.0 mg/dl, Phosphorus 2.2 mg/dl, BUN 37 mg/dl, Creatinine 1.8 mg/dl. Which of the following is the most likely diagnosis?