USMLE Pediatry paraclinic pédiatrie for student 122 QCM

1) The parents of a 3-year-old patient followed in your clinic recently took their child on quickly planned 5-day trip to Africa to visit an ill grandparent. Everyone did well on the trip, but since their return about 10 days ago the boy has been having intermittent, spiking fevers associated with headache, sweating, and nausea. The parents had not been too concerned since he was relatively well, except for being tired, between the fevers. Today, however, they feel that he looks a bit pale and his eyes appear “yellow.” Which of the following is likely to reveal the source of his problem?

2) An 11-month-old girl is brought by her mother to the office due to fever, fussiness, and irritability. The girl has a tendency to hold and pull on her left ear. For the past few days, she has had rhinorrhea and nasal congestion. Her medical history reveals nothing particular. Her temperature is 38.9C (102F). Otoscopic examination reveals a bulging, erythematous tympanic membrane with decreased mobility on air compression. What is the most likely organism responsible for the patient's condition?

3) A 1-day-old normal-appearing infant develops tetany and convulsions. He was born at 34 weeks’ gestation with Apgar scores of 2 and 4 (at 1 and 5 minutes, respectively) to a woman whose pregnancy was complicated by diabetes mellitus and pregnancy-induced hypertension. Which of the following serum chemistry values is likely to be the explanation for his condition?

4) A neonate is noted to have aniridia of the right eye on physical examination. He was born by spontaneous vaginal delivery after an uncomplicated full-term pregnancy. The remainder of the physical examination is normal. Which of the following is the most appropriate next step before the infant is released from the hospital?

5) An 11-month-old boy is brought to the emergency department by his parents. The child has a fracture of the right femur. The father reports this was sustained as a result of falling out of the crib. The child is also noted to have bruises on his shoulders and back. The rest of his examination is unremarkable. Which of the following is the most appropriate next step in diagnosis?

6) A 7-year-old boy is brought to the clinic for a lifetime history of bedwetting. He has otherwise been completely healthy and has met all development milestones. His parents deny a history of trauma, and the history is not consistent with abuse. The patient has been wetting every night but not during the daytime. He has no incontinence. Which of the following is the most appropriate next step in his evaluation?

7) A 4-year-old child has mental retardation, shortness of stature, brachydactyly (especially of the fourth and fifth digits), and obesity with round facies and short neck. The child is followed by an ophthalmologist for subcapsular cataracts, and has previously been noted to have cutaneous and subcutaneous calcifications, as well as perivascular calcifications of the basal ganglia. This patient is most likely to have which of the following features?

8) A 30-hour-old infant has not passed meconium since birth. He was full term with a birth weight of 3856 g (8 lb 8 oz). The pregnancy was uncomplicated. The baby appears well with no respiratory distress. Slight abdominal distention is noted. Rectal examination reveals a slightly tight rectum and results in a greenish gush of stool. Which of the following tests will probably confirm the likely diagnosis?

10) A 10-year-old child arrives with the complaint of new-onset bed-wetting. He has had no fever, his urine culture is negative, and he has had no new stresses in his life. He is well above the 95th percentile for weight as is much of his family. Which of the following is most helpful in making a diagnosis?

11) A 2-year-old child is brought to the physician for a routine visit. He is growing and developing appropriately. He 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 shows mild pallor. Laboratory studies show the following: Hemoglobin 9.5 g/dL, RDW 21%, MCV 70 fl, Platelet count 284,000/mm3, Leukocyte count 6,500/mm3. Which of the following additional findings is most likely in this patient?

12) A 2-month-old infant is brought to the emergency department with irritability and lethargy. The parents state that he was well until he rolled off the couch on to the floor yesterday. On examination, he is inconsolable and afebrile. The fontanels are full and tense. He has a generalized tonic-clonic seizure. Which of the following is the most important initial diagnostic study to order?

13) A 6-month-old male infant is brought to the physician's office by his mother due to failure to thrive. According to the mother, the child always regurgitates shortly after feedings, and has even had a few episodes of blood-stained projectile vomiting. During the vomiting episodes, the child tilts his head to the left and arches his back. On examination, the child is afebrile. His abdomen is soft and non-tender to palpation. Laboratory evaluation shows hypochromic microcytic anemia. What is the most appropriate test to confirm the most likely diagnosis of this child?

14) Which of the following is the most appropriate evaluative procedure for an otherwise normal 7-day-old boy with perineal hypospadias?

15) A 10-year-old boy has a long history of recurrent infections. These have included pneumonia, suppurative lymphadenitis, persistent rhinitis, dermatitis, diarrhea, and perianal abscesses. Involved organisms have included Staphylococcus aureus, Serratia, Escherichia coli, and Pseudomonas. Biopsy of skin and lymph nodes have demonstrated granulomatous lesions, even though the only species isolated were those noted above. Immunoglobulin levels are higher than normal. Which of the following findings would be most helpful in establishing the diagnosis?

16) A previously healthy 15-month-old girl is brought to the emergency department after she had several episodes in which she lost consciousness after crying. Her parents state that the episodes always occur when the child gets frustrated or upset. She has no cyanosis or incontinence. The episodes last about 45 seconds each. After the episode, she is alert and appropriate. Physical examination is unremarkable. What is the next best step in the management of this patient?

17) A male infant born at term is found to have bilateral colobomas, choanal atresia, ear anomalies, and cryptorchidism. There is no history maternal drug or alcohol abuse during pregnancy. There is no family history of similar congenital defects. Which of the following is the most appropriate initial test to exclude any associated abnormalities?

18) A 10-year-old patient with sickle cell disease comes to the physician for a routine visit. The patient has a history of multiple pain crises and pneumonias. He was started on hydroxyurea one year ago and has not had any further pain crises since then. He has had no recent illnesses or hospitalizations. His physical examination is unremarkable. The patient's laboratory results are shown below. Complete blood count: Hemoglobin 9.0 g/L, Erythrocyte count 2.2 mln/mm3, MCHC 32%, MCV 105 fl, Reticulocytes 2.0%, Platelets 212,000/mm3, Leukocyte count 9500/mm3, Neutrophils 56%, Eosinophils 3%, Lymphocytes 36%, Monocytes 5%. Which of the following best describes the role of hydroxyurea in the treatment of patients with sickle cell disease?

19) A 3-year-old boy is brought to the ER with a two-day history of decreased appetite, neck swelling, and irritability. He keeps his head rotated slightly to the right side. He resists passive flexion of the neck and rotation to the left side. Which of the following is the best next step in managing this patient?

20) The parents of a 2-month-old baby boy are concerned about his risk of coronary artery disease because of the recent death of his 40-year-old maternal uncle from a myocardial infarction. Which of the following is the most appropriate management in this situation?

21) A 5-month-old infant is brought to the physician for a routine visit. The child was born full term without complications. The infant has been seen several times for poor weight gain. The infant takes 5 ounces of formula every 4 hours, and has been tried on increased calorie formula without success. Family history is significant only for nephrolithiasis. On examination, the infant's weight is <5%, height is at the 20% and head circumference is at the 20%. The infant appears thin, but the remainder of the physical examination is unremarkable. Screening labs are shown below. Chemistry panel: Serum sodium 140 mEq/L, Serum potassium 3.0 mEq/L, Chloride 113 mEq/L, Bicarbonate 15 mEq/L, Blood urea nitrogen (BUN) 10 mg/dl, Serum creatinine 0.5 mg/dl, Calcium 9.0 mg/dl, Blood glucose 98 mg/dl. The urine pH is 7.9 and urinary sodium and potassium are within normal limits. What is the most likely cause for this patient's failure to thrive?

22) A 6-year-old boy has had a fever for 8 days. He just finished a 5-day course of amoxicillin for otitis media. On examination, his temperature is 38.6 C (101.4 F). He has meningismus and palsy of the left sixth cranial nerve. Cerebrospinal fluid (CSF) analysis reveals 200 white cells per mL with 80% lymphocytes and 20% polymorphonuclear leukocytes, glucose of 18 mg/dL, protein of 260 mg/dL, and a negative Gram stain. There is basilar enhancement without focal lesions on CT. Which of the following CSF tests will most likely identify the cause of meningitis?

23) An 18-month-old boy is brought to the clinic for a checkup. As part of his routine care, a serum lead level is obtained. It is 25 g/mL. Which of the following is the most appropriate next step in his management?

24) A 3-month old infant is brought to a pediatrician's office because of increased lethargy and irritability. The parents state that the child rolled off the couch and fell on the floor one day prior to presentation. His parents report that the child has been previously healthy and is up to date on his vaccinations. He has been meeting his development milestones. His fontanelles are full. While in office the patient develops a tonic-clonic seizure. Which of the following is the next appropriate step?

25) A 4-year-old girl was diagnosed of left-side otitis media about 10 days ago and was prescribed oral amoxicillin, 40 mg/kg/day for 7 days. She has since developed bloody diarrhea with mucus, crampy abdominal pain, and fever. On physical examination, her temperature is 39.4 C (102.9 F), pulse is 88/min, and respirations are 16/min. She has normal bowel sounds and is diffusely tender to palpation. Which of the following is the most appropriate initial step in diagnosis?

26) A 4-week-old infant is brought to the office due to several episodes of vomiting over the past week. The episodes have progressively become more frequent and forceful, but the vomitus never contains any blood or bile. The infant has been breastfed since birth. His vital signs are stable, and he is afebrile. An olive-shaped mass is palpated just to the right of the umbilicus, and peristaltic waves are seen in the upper abdomen. Lab studies reveal a sodium level of 135 mEq/L, potassium level of 3.3 mEq/L, chloride level of 92 mEq/L and bicarbonate level of 30 mEq/L. Which of the following is the most appropriate diagnostic test for this patient?

27) A 5-year-old boy presents to the emergency department with 2-day history of fever, anorexia, loose stools, and yellow skin color. He attends a large daycare center. On physical examination, his temperature is 38.1 C (100.7 F), blood pressure is 88/56 mm Hg, pulse is 74/min, and respirations are 15/min. Initial laboratory evaluation reveals a total bilirubin of 1.8 mg/dL and alanine aminotransferase of 764 U/L. Which of the following is the most appropriate diagnostic test?

28) A 6-year-old child is hospitalized for observation because of a short period of unconsciousness after a fall from a playground swing. He has developed unilateral pupillary dilatation, focal seizures, recurrence of depressed consciousness, and hemiplegia. Which of the following is the most appropriate management at this time?

29) A 2-year-old boy has been doing well despite his diagnosis of tetralogy of Fallot. He presented to an outside ER a few days ago with a complaint of an acute febrile illness for which he was started on a “pink antibiotic.” His mother reports that for the past 12 hours or so he has had a headache and is more lethargic than normal. On your examination he seems to have a severe headache, nystagmus, and ataxia. Which of the following would be the most appropriate first test to order?

30) In an adolescent presenting with pityriasis rosea, which of the following would be an appropriate blood test to order?

31) A 2-year-old boy with cough and difficulty breathing is brought to the emergency department by his mother. She says that he was well and playing with his toys until 2 hours prior to presentation. He is healthy, but his 6-year old brother has a peanut allergy. The patient's temperature is 36.7 C (98 F), blood pressure is 92/48 mmHg, pulse is 114/min, and respirations are 48/min. The patient's pulse oximetry shows 91 % on room air. Physical examination shows nasal flaring and grunting with both subcostal and intercostal retractions. Wheezing is heard in the right lung field; the left field is clear to auscultation. No rales or rhonchi are noted. The remainder of the physical examination is within normal limits. Supplementary oxygen is applied. Chest x-ray reveals mild hyperinflation of the right lung. Which of the following is the most appropriate next step in management of this child?

32) An 8-year-old boy is brought to the emergency department by his mother. Two weeks ago, he developed a low-grade fever followed by a persistent cough. He occasionally has severe paroxysms of cough that are precipitated by eating and do not resolve with antitussive medications. On physical examination, extensive subcutaneous emphysema over the anterior chest is noted. What is the most appropriate next step in the management of this patient?

33) During a routine yearly checkup, a 10-year-old boy is found to have 2+ proteinuria on urinalysis. Which of the following would be the most appropriate diagnostic test?

34) An infant has had repeated pneumonias and middle ear infections that began at about 5 months of age. At 1 year of age, serum electrophoresis demonstrated hypogammaglobulinemia. T cell function was normal. By 2 years of age, the child's infection rate has decreased, and repeat serum electrophoresis is normal. Which of the following immunoglobulins was likely decreased in this child during the period of increased susceptibility to infection?

35) A 12-year-old, previously healthy girl presents to her physician with a chief complaint of early morning headaches. She states that these headaches wake her up from sleep 2-3 days a week. She also complains of some vomiting associated with the headaches. The headaches have been getting progressively worse for the past 2 months. She denies any photophobia, dizziness, or blurred vision. There is no history of a recent respiratory infection, runny nose, or cough. There is no history of recent trauma. In the office, her vital signs are within normal limits. Her examination shows pupils that are equal, round, and reactive, with no maxillary or frontal sinus tenderness. Her tympanic membranes are clear and intact. Her neck is supple with full range of motion. Neurologic examination shows a positive Romberg sign. Which of the following tests would most likely confirm the diagnosis?

36) A 4-year-old child manifests symptoms of fever, sore throat, and swollen lymph nodes. The spleen tip is palpable. Throat culture and rapid slide (Monospot) test results are negative. The next logical diagnostic procedure would involve which of the following?

37) A 17-year-old adolescent female is 6 weeks postpartum. She presents to the emergency room with the complaints of increased jaundice, abdominal pain, nausea, vomiting, and fever. Her examination is remarkable for jaundice, pain of the right upper quadrant with guarding, and a clear chest. Chest radiographs appear normal. Which of the following tests is most likely to reveal the cause of this pain?

38) An 8-year-old is accidentally hit in the abdomen by a baseball bat. After several minutes of discomfort, he seems to be fine. Over the ensuing 24 hours, however, he develops a fever, abdominal pain radiating to the back, and persistent vomiting. On examination, the child appears quite uncomfortable. The abdomen is tender, with decreased bowel sounds throughout, but especially painful in the midepigastric region with guarding. Which of the following tests is most likely to confirm the diagnosis?

39) A 10-month-old baby boy, recently adopted from Guyana, has a 5-hour history of crying, with intermittent drawing up of his knees to his chest. On the way to the emergency room he passes a loose, bloody stool. He has had no vomiting and has refused his bottle since the crying began. Physical examination is noteworthy for an irritable infant whose abdomen is very difficult to examine because of constant crying. His temperature is 38.8C (101.8F). The rectal ampulla is empty, but there is some gross blood on the examining finger. Which of the following studies would be most helpful in the immediate management of this patient?

40) A 5-month-old male infant has a urine output of less than 0.1 mL/kg/hr shortly after undergoing major surgery. On examination, he has generalized edema. His blood pressure is 94/48 mm Hg, pulse is 140/min, and respirations are 20/min. His blood urea nitrogen is 38 mg/dL, and serum creatinine is 1.4 mg/dL. Initial urinalysis shows a specific gravity of 1.018 and 2+ protein. Microscopic examination of the urine sample reveals 1 WBC per high-power field (HPF), 18 RBCs per HPF, and 5 granular casts per HPF. His fractional excretion of sodium is 3.2 %. Which of the following is the most appropriate next step in diagnosis?

41) A young Hispanic couple brings their first child to their physician for a well-child examination. The child is a 3-month-old healthy-appearing infant, whose weight is at the 45th percentile of the normal growth curve. During examination, the physician observes an area of blue-black pigmentation over the buttocks. The parents say that it was present from the time of birth. Which of the following is the most appropriate next step in management?

42) A 2-year-old boy is brought to the clinic because of a swelling at the base of his neck on the left side. The family indicates that since he was born, they suspected he had some kind of a mass in his left supraclavicular area and behind the sternomastoid on that same side, but the area felt soft and mushy, was not always evident, and seemed to be painless, so they did nothing about it. Two weeks ago the child had an upper respiratory infection, and within a day or two the mass became larger and quite obvious. On physical examination he indeed has a soft, mushy, ill-defined mass occupying the entire left supraclavicular area and extending into the posterior triangle of the neck. He has no enlarged lymph nodes anywhere, and his spleen and liver are not palpable. Which of the following is the most appropriate next step in the evaluation?

43) A 9-month-old infant is brought to the pediatrician's office because his weight is persistently below the 10th percentile. His mother states that the infant seems to be hungry all the time and usually consumes 8-12 oz of formula every 2-3 hours in addition to some table food. He also has frequent, bulky, and malodorous stools. A malabsorption syndrome is suspected. The results of which of the following tests will most likely be abnormal?

44) A 6-week-old child is being evaluated for a fever of unknown etiology. As part of the laboratory evaluation, a urine specimen was obtained that grew E coli with a colony count of 2000/μL. These findings would be definite evidence of a urinary tract infection if which of the following is true about the sampled urine?

45) An obese Caucasian father brings his 1 0-year-old obese son to your office. The father states that he was recently diagnosed with high cholesterol levels and coronary artery disease. Even though his son is asymptomatic, he is worried about the obesity. Which of the following best explains the next best step in management?

46) A full-term infant is born after a normal pregnancy; delivery, however, is complicated by marginal placental separation. At 12 hours of age, the child, although appearing to be in good health, passes a bloody meconium stool. For determining the cause of the bleeding, which of the following diagnostic procedures should be performed first?

47) A 1-year-old boy is brought to the pediatrician for a routine visit. While talking to his mother, she reports that they moved into an old house several months ago and are in the process of renovating. The child eats table food and drinks whole milk. His height, weight, and head circumference are all at the 50th percentile for his age. Physical examination is normal. The results of a fingerstick blood test are shown below: Hemoglobin 10.5 g/dL, Hematocrit 30.0%, Lead level 12 μg/dL (Normal < 10 μg/dL). Which of the following is the most appropriate next step in management?

48) A father brings his 3-year-old daughter to the emergency center after noting her to be pale and tired and with a subjective fever for several days. Her past history is significant for an upper respiratory infection 4 weeks prior, but she had been otherwise healthy. The father denies emesis or diarrhea, but does report his daughter has had leg pain over the previous week, waking her from sleep. He also reports that she has been bleeding from her gums after brushing her teeth. Examination reveals a listless pale child. She has diffuse lymphadenopathy with splenomegaly but no hepatomegaly. She has a few petechiae scattered across her face and abdomen and is mildly tender over her shins, but does not have associated erythema or joint swelling. A CBC reveals a leukocyte count of 8,000/μL with a hemoglobin of 4 g/dL and a platelet count of 7,000/μL. The automated differential reports an elevated number of atypical lymphocytes. Which of the following diagnostic studies is the most appropriate next step in the management of this child?

49) A recovering premature infant who weighs 950 g (2 lb, 1 oz) is fed breast milk to provide 120 cal/kg/d. Over the ensuing weeks, the baby is most apt to develop which of the following?

50) A 15-year-old boy has been immobilized in a double hip spica cast for 6 weeks after having fractured his femur in a skiing accident. He has become depressed and listless during the past few days and has complained of nausea and constipation. He is found to have microscopic hematuria and a blood pressure of 150/100 mm Hg. Which of the following is the most appropriate course of action?

51) A 14-year-old boy comes to the office because he has been feeling a mass under his right nipple for the last three weeks. The physical examination reveals clinical findings suggestive of right gynecomastia with very mild tenderness. The left breast and the rest of the physical exam is unremarkable. His testis is 2 cm in length and has 3 ml volume. What is the most appropriate next step in the management of this patient?

52) A 14-year-old boy is brought to your office by his mother because of a two-week history of generalized edema, fatigue, and abdominal pain. His past medical history is insignificant, and the boy is not taking any medications. His BP is 110/70 mmHg and heart rate is 80/min. Urinalysis reveals proteinuria 4+, but urine sediment findings are within normal limits. Which of the following light microscopy finding would you expect in this patient's kidney biopsy?

53) A 5-week-old bottle-fed boy presents with persistent and worsening projectile vomiting, poor weight gain, and hypochloremic metabolic alkalosis. Of the following diagnostic modalities, which would most likely reveal the diagnosis?

54) You are asked by a colleague to evaluate a 5-year-old boy as a second opinion. He has a history of chronic and recurrent upper respiratory tract infections, several admissions to the hospital for pneumonia, and three surgeries for PE tubes for chronic otitis media. Of note is a right-sided heart on repeated radiographs. Convinced you know the diagnosis based on history alone, you confirm your diagnosis with a biopsy of the nasal mucosa. You expect to find which of the following?

55) A 13-year-old patient with sickle-cell anemia presents with respiratory distress; she has an infiltrate on chest radiograph. The laboratory workup of the patient reveals the following: hemoglobin 5 g/dL; hematocrit 16%; white blood cell count 30,000/μL; and arterial blood (room air) pH 7.1, PO2: 35 mm Hg, and PaCO2: 28 mm Hg. These values indicate which of the following?

56) A 6-month-old child was noted to be normal at birth, but over the ensuing months you have been somewhat concerned about his slowish weight gain and his mild delay in achieving developmental milestones. The family calls you urgently at 7:00 AM noting that their child seems unable to move the right side of his body. Which of the following conditions might explain this child’s condition?

57) A 3-year-old girl with a ventricular septal defect (VSD) presents to the emergency department after a 15-minute focal seizure of her left arm and leg. A brief history reveals that the child has no known seizure disorder and has been having a low-grade fever at home for about 4 days. She also has been less active and has had poor appetite. On physical examination, her temperature is 40.2 C (104.3 F), and her pulse is 82/min. She is not responsive to her name, but she is responsive to painful stimuli with withdrawal of her extremities. Cardiac examination is significant for a grade 3 systolic murmur best heard at the left lower sternal border. Neurologic examination reveals anisocoria with a dilated right pupil. After stabilization, which of the following is the most appropriate next step in diagnosis?

58) A 20-month-old male is brought to the emergency department for evaluation of rectal bleeding after his parents discovered a substantial amount of maroon colored stool when changing his diaper. He has no history of hematochezia. The patient has been otherwise healthy and has not appeared to be in any pain. He has been eating and drinking well. His temperature is 37 C (98.6 F), blood pressure is 85/50 mmHg, pulse is 130/min, and respiratory rate is 20/min. On examination, the abdomen is soft, nondistended, and nontender. On rectal examination, there are no fissures or masses present. A fecal occult blood test is positive. The remainder of the physical examination is normal. Which of the following is the best test to confirm the diagnosis?

59) A 7 -year-old African American boy is brought to your clinic with complaints of bedwetting. He was toilet trained at the age of 4. He has been able to pass urine normally in daytime, but has never been dry at night. There is no history of urgency or frequency during daytime. There is no history suggestive of child abuse. He had two episodes of urinary tract infections (UTI) from birth until he was 2-years-old, but he has not had any episodes ever since. What is the next best step in the management of this patient?

60) A 1-month-old male infant is brought to the emergency department by his mother due to a 3-day history of projectile vomiting. He has been formula- fed since birth, and his bowel movements are normal. He has never been ill before. His parents and 4-year-old sister are all healthy. One of his maternal uncles is mentally retarded. He weighs 3.1 kg (7 Ib). Physical examination reveals fair hair and skin, blue eyes, eczematous rash, and mild signs of dehydration. His urine has a mousy odor. What is the most appropriate screening test for this patient's early diagnosis and treatment?

61) A 7-year-old boy is brought to the physician because of persistent nasal obstruction for 6 months. There is no: personal or family history of allergic disorders. Examination of the nasal fossae reveals bilateral ethmoidal polyps that protrude into the middle meatus and nasal cavity. Which of the following is the most appropriate next step in diagnosis?

62) A 3-year-old African American boy is brought to the emergency department with sudden onset of difficulty walking. His mother reports that his right hand also seems "clumsy." The boy's past medical history is significant for a hospitalization one year ago for severe upper extremity pain and hand swelling. On physical examination, he has a blood pressure of 90/60 mmHg, heart rate of 120/min, temperature of 36.7°C (98°F), and respiratory rate of 22/min. Which of the following would be most helpful in diagnosing his condition?

63) A 15-year-old boy with tall stature presents with decreased exercise tolerance over the past 2 months. He states that he used to play two games of basketball with no problem, but he now can play only one game. On physical examination, his weight is at the 25th percentile, and his height higher than the 95th percentile. He is thin and has a gangly body habitus. His fingers are long and thin. There is pectus deformity in his chest. His joints are hyperextensible. An ophthalmologic examination reveals mild subluxation of the lens. Which of the following is the most likely finding on an echocardiogram?

64) A 15-year-old otherwise healthy boy presents with a complaint of intermittent abdominal distention, crampy abdominal pain, and excessive flatulence. He first started noticing these symptoms when he moved into his father’s house, and his stepmother insisted on milk at dinner every night. He has normal growth, has not lost weight, and has no travel history. Which of the following is the most appropriate study to diagnose his condition?

65) A 6-week-old infant is admitted to the hospital with jaundice. Her outpatient blood work demonstrated a total bilirubin of 12 mg/dL with a direct portion of 3.5 mg/dL. Which of the following disorders is most likely to be responsible?

66) A 9-month-old child comes in for a routine visit. She has had several episodes of otitis media in the past, but no major illnesses or hospitalizations. Her mother is concerned because the child was previously happy and social around other people, but now cries if her mother is not in the room. The child constantly wants to be held by her mother and becomes upset if her mother walks into the next room. Her grandmother keeps her during the day, and she now cries when her mother leaves her in the morning. Developmentally, she is crawling and waves bye-bye. She does not yet respond to her name or say words. She previously babbled but stopped several months ago. When you hide a toy with your hand, she lifts your hand to look for the toy. Which of the following is the best next step in the management of this child?

67) As a city public health officer, you have been charged with the task of screening high-risk children for lead poisoning. Which of the following is the best screen for this purpose?

68) The 1-year-old brother of a child with known abetalipoproteinemia is evaluated by a pediatrician for the disease. The 1 -year-old has been exhibiting steatorrhea and ataxia. Which of the following would most strongly support the suspected diagnosis?

69) A 2-year-old boy is brought to the emergency department (ED) in acute respiratory distress. He is afebrile, and has a heart rate of 100/min, respiratory rate of 80/min, and Sa02 of 84% on room air. He is sitting upright, and has significant nasal flaring and intercostal retractions. He is given supplemental oxygen in the ED. Chest x-ray reveal hyperinflation of the right lung, mediastinal shift to the left, and a severely hypoinflated left lung Which of the following is the most appropriate next step in management?

70) A 2-year-old presents to the emergency center with several days of rectal bleeding. The mother first noticed reddish-colored stools 2 days prior to arrival and has since changed several diapers with just blood. The child is afebrile, alert, and playful, and is eating well without emesis. He is slightly tachycardic, and his abdominal examination is normal. Which of the following is the best diagnostic study to order to confirm the diagnosis?

71) A 16-month-old girl is brought to medical attention because of irritability, poor feeding, and temperatures up to 39.4 C (103 F). Careful history and physical examination fail to disclose any identifiable cause of her fever. There is some degree of abdominal tenderness on palpation. Which of the following is the most appropriate next step in diagnosis?

72) A 3-year-old child presents to your office for an evaluation of constipation. The mother notes that since birth, and despite frequent use of stool softeners, the child has only about one stool per week. He does not have fecal soiling or diarrhea. He was born at term and without pregnancy complications. The child stayed an extra day in the hospital at birth because he did not pass stool for 48 hours, but has not been in the hospital since. Initial evaluation of this child should include which of the following?

73) A 4-year-old boy falls from the jungle gym at preschool. He sustains minor abrasions and contusions, and is taken care of by the school nurse. His parents take him that same afternoon to his regular pediatrician and demand "a thorough check-up" for possible internal injuries. The pediatrician complies, and a complete physical examination is normal. His hemoglobin is 14 g/dL, and a urinalysis shows the presence of microhematuria. Which of the following is the most appropriate next step in management?

74) A 4-year-old child is brought to the emergency department after he ingested liquid oven cleaner. His vital signs are stable. He is crying and drooling with blood-tinged secretions. His lips and chin are swollen and erythematous. His clothes are contaminated with the material. His breathing appears normal. His lungs are clear. Based on these findings, what is the best next step in the management of this patient?

75) A 4-week-old male infant is brought to the office due to several episodes of projectile vomiting for the last few days. The vomitus contains milk and doesn't contain bile or blood. The child's appetite has increased for the last few days. He has been fed with goat's milk since birth, but doesn't seem to tolerate it anymore for the last few days. He vomits a few minutes after feedings. He appears dehydrated, and abdominal examination reveals no mass. Blood tests reveal macrocytosis. What is the most appropriate next step in the management of this patient?

76) A 6 month old male is brought in to the Emergency Room by his mother who states that when she picked him up from the baby-sitter he was not acting right. The baby-sitter stated that he was sleeping more and was fussy. On examination the baby is stuporous. His temperature is 37.8 C (99.9 F), pulse is 140/min, and respirations are 36/min. A 4 cm ecchymosis is noted on his right cheek. The remainder of the physical examination is unremarkable. The physician suspects possible physical abuse. He orders a CT scan of the head, skeletal survey, chemistry panel and complete blood count. Which of the following diagnostic tests should also be ordered?

77) A 4-year-old boy, recently adopted through an international adoption service, is noted to have intermittent watery diarrhea, nausea, belching, and abdominal pain. His weight is less than the fifth percentile for his age. Which of the following studies would be most helpful in making the diagnosis?

78) A 10-month-old infant has poor weight gain, a persistent cough, and a history of several bouts of pneumonitis. The mother describes the child as having very large, foul-smelling stools for months. Which of the following diagnostic maneuvers is likely to result in the correct diagnosis of this child?

79) A 14-year-old African-American girl presents to the ER with a mild fever and severe right-sided thigh pain. She is agitated and requests quick pain relief. Her heart rate is 120/min and blood pressure is 120/70 mmHg. She says that she had a similar episode one year ago and was placed in the hospital for intravenous pain management. Her brother had similar episodes and died of an infection at 10 years of age. Which of the following would you most expect to see on this patient's peripheral blood smear?

80) You are asked to evaluate an infant born vaginally 3 hours previously to a mother whose only pregnancy complication was poorly controlled gestational diabetes. The nursing staff noticed that the infant was breathing abnormally. On examination, you find that the infant is cyanotic, has irregular, labored breathing, and has decreased breath sounds on the right side. You also note decreased tone in the right arm. You provide oxygen and order a stat portable chest radiograph, which is normal. Which of the following studies is most likely to confirm your diagnosis?

81) A 3-year-old boy of African descent is brought to your office by his stepfather because of easy bruising. He says that the child bruises easily even without trauma. The child started playing games by himself recently. He has a past history of clavicular fracture, which the stepfather attributes to a fall down a set of stairs. The history of the biological father is unknown. On examination, there is a right knee effusion with decreased range of motion, and multiple soft tissue hematomas on the thigh. What is the most appropriate diagnostic step in management?

82) An 8-year-old boy presents to the pediatrician's office with a headache for the past 3 weeks. His mother also states that he has been more tired and has had frequent nose bleeding for the past month. On physical examination, his height and weight are both below the 5th percentile for his age. His blood pressure is 152/86 mm Hg in all four extremities. His pulse is 74/min, and respirations are 16/min. His heart examination is normal with no murmur. His peripheral pulses are strong and symmetric. Urinalysis and serum electrolytes are ordered. Which of the following is the most appropriate next step in diagnosis?

83) A 15-year-old girl presents with diplopia after prolonged reading and ptosis that worsens in the afternoon. On examination, she is noted to have bilateral ptosis, impaired extraocular muscle movements, facial weakness, and generalized hypotonia and weakness increasing with repetition. Which of the following is the best diagnostic test for this disorder?

84) A 7-day-old boy who is the product of an uncomplicated gestation is brought to the physician because of hypospadias. The baby is otherwise healthy, and is urinating without any difficulty. On physical examination, vital signs are stable, lungs are clear and the heart is beating at a regular rate. The only abnormal physical finding is the hypospadias. Urinalysis is negative for infection. Which of the following is the most appropriate next step?

85) A 12-year-old girl has a solitary thyroid nodule found on routine examination; she has no symptoms. Which of the following is the most appropriate next step for this patient?

86) A 5-year-old boy develops a headache, cough, myalgia and a fever. He has been a healthy child with all immunizations up to date. He is given a decongestant and an aspirin for his symptoms with some relief. However, 4 days later, he is brought back by his parents because of persistent vomiting and irritability. On physical examination, he is found to be semicomatose, becoming combative on stimulation. Which of the following levels should be measured to aid in the diagnosis of this patient?

87) A 3-year-old boy is admitted for seizure-like activity. He has been a healthy child and has been meeting all development milestones. His immunization schedule is up-to-date. Examination is notable for an erythematous throat and fever. His convulsions require IV administration of a benzodiazepine. Serum analysis reveals a normal white cell count with mild basophilic stippling. The lumbar puncture reveals elevated CSF pressure. Head CT scan is notable for cerebral edema. Which of the following is the next diagnostic step?

88) A 3-day-old, full-term baby boy is brought into the emergency department because of feeding intolerance and bilious vomiting. X-rays films show multiple dilated loops of small bowel and a "ground glass" appearance in the lower abdomen. The mother has cystic fibrosis. Which of the following diagnostic tests would also have therapeutic value?

89) A 5-year-old boy is brought to clinic with increasing right lower foot pain. He stepped on a nail several days ago. At that time, the family had sought medical attention. The child was given a tetanus shot, and the wound was extensively irrigated. On examination, the foot is tender, swollen, warm, and erythematous. Osteomyelitis is suspected. Which of the following is the most appropriate next step in diagnosis?

90) A 15-year-old African-American girl has a facial rash and vague joint pains. Her temperature is 37.2C (99F). On examination, a malar erythematous rash is noted. Her laboratory evaluation is significant for anemia, leukopenia, and a normal platelet count. Her antinuclear antibody and Rapid Plasma Reagin (RPR) tests are positive. Which of the following tests is confirmatory for this patient's condition?

91) A 15-year-old Caucasian female comes to your office because her menses have not yet started. Her breast development is Tanner stage 2 and there is scant pubic hair. Physical examination is also significant for decreased femoral pulses. Which of the following is the best next step in evaluating her condition?

92) A 5-year-old boy is brought to the clinic by his mother because he was sent home by the school nurse. The nurse claims to have heard a murmur in his chest. The child has always been healthy, and has never had any shortness of breath, chest pain, dizziness or any other illnesses. On examination, the child appears alert, and his vital signs are stable. Auscultation of the chest reveals a grade-2 systolic ejection murmur at the left sternal border, but no other extra sounds. The murmur changes with position. What is the best next step in the management of this patient?

93) A 4-year-old boy was admitted to the hospital last night with the complaint of “difficulty breathing.” He has no past history of lung infection, no recent travel, and no day-care exposure; he does, however, have an annoying tendency to eat dirt. In the emergency center he was noted to be wheezing and to have hepatomegaly. He is able to talk, relaying his concern about his 6-week-old Chihuahua being left alone at home. Laboratory studies revealed marked eosinophilia (60% eosinophils). Which of the following tests is most likely to produce a specific diagnosis?

94) A 2-year-old boy who emigrated from Eastern Europe 1 year ago is brought to the physician because of fever, cough, and night sweats for 3 weeks. The child's grandmother, who lives with him, has similar symptoms. The child's temperature is 39.2 C (102.6 F), Wood pressure is 110/65 mm Hg, pulse is 90/min, and respirations are 28/min. A Mantoux test is reactive, and a chest x-ray film shows a right middle lobe infiltrate and hilar lymphadenopathy. Which of the following is the most appropriate next step in diagnosis?

95) An otherwise healthy 17-year-old complains of swollen glands in his neck and groin for the past 6 months and an increasing cough over the previous 2 weeks. He also reports some fevers, especially at night, and possibly some weight loss. On examination, you notice that he has nontender cervical, supraclavicular, axillary, and inguinal nodes, no hepatosplenomegaly, and otherwise looks to be fairly healthy. Which of the following would be the appropriate next step?

96) A 3-year-old girl is brought to the pediatrician with complaints of abdominal pain and fever. Her mother states that the fever started 2 days ago, with the highest temperature being 39.0 C (102.2 F). She has had no vomiting or diarrhea. The mother states that her daughter has been complaining of pain on urination. On examination, she is tender in her lower abdomen, and there is some right-sided costovertebral angle tenderness. A urinalysis confirms the suspicion of a urinary tract infection. Which of the following would be the most appropriate diagnostic procedure?

97) A 7 -year-old male child is brought to the office due to decreased urine output and lethargy for the past week. His birth and past medical histories are insignificant. His immunizations are up-to-date. Examination reveals no abnormalities. His BUN and creatinine levels are elevated. What is the most appropriate next step in the management of this patient?

98) A 6-year-old girl is brought to the office for the evaluation of "passing smoky urine." She recently had a sore throat. Her blood pressure is 150/100 mmHg. There is swelling of the face and extremities. Urinalysis reveals many red blood cells, red blood cell casts and 1 + proteinuria. Her serum C3 level and CH 50 are low. Her C4 1evel is normal. Her antistreptolysin-a (ASO) titer is 1,024 Todd units (normal ≤ 166 Todd units). In this patient, which of the following abnormal findings is most likely to become normal within 8 to 12 weeks?

99) A 2-year-old girl is brought to the emergency department with a fever, chills, poor appetite, and vomiting. On examination, she is irritable and diaphoretic. Her temperature is 39.2 C (102.5 F), blood pressure is 80/48 mm Hg, pulse is 88/min, and respirations are 17/min. She is tender at the left costovertebral angle. Initial laboratory tests show the following: Leukocyte count 16,300/mm3, Hemoglobin 12.5 g/dL, Platelet count 245,000/mm3, Blood urea nitrogen 6 mg/dL, Creatinine 0.5 mg/dl. Urinalysis is positive for leukocyte esterase and nitrite, with 150 white blood cells/hpf. After TV antibiotic administration and stabilization, what is the most appropriate diagnostic study?

100) A 9-year-old girl is brought to the clinic with complaints of fatigue, abdominal pain and low grade fever. Four days ago her mother noticed a red rash on the tops of her daughter's feet, which has now spread to her thighs and buttocks. The rash was initially small red dots, but has now become patches. Her daughter subsequently developed periumbilical, cramping, abdominal pain. Review of systems is positive only for a respiratory viral illness three weeks ago. Her temperature is 37.7 C (99.8 F), pulse is 96/min, and respirations are 18/min. Abdominal examination is remarkable for tenderness to palpation near the umbilicus, but the abdomen is otherwise soft, with no rebound or guarding, and no organomegaly. Raised, palpable purpuric lesions are present on the buttocks and thighs. The ankles are tender and edematous bilaterally. Complete blood count reveals a leukocyte count of 9,000/mm3. Her hemoglobin 12. 6 g/dL, and platelets are 325,000/mm3. Serum electrolytes are normal. Which of the following is her urinalysis most likely to reveal?

101) A 6-year-old girl is brought to the office due to significant steatorrhea and failure to thrive. She has a poor appetite and general malaise. Her past medical history is significant for prolonged neonatal jaundice and numerous respiratory tract infections. On examination, she looks a little underweight and has a runny nose. Auscultation reveals mild wheezing and diminished air entry in both lungs. Clubbing is visible on both hands. What is the best diagnostic test for this patient?

102) A 6-year-old girl is brought to the emergency room because her urine is red. She has been healthy her whole life, and has recently returned from an outing with her grandmother to a local amusement park. Her urine dip for heme is positive, suggesting which of the following is a possibility?

103) A 6-year-old boy with mental retardation has recently been diagnosed with Fragile X syndrome. His 9-year-old sister appears to be of normal intelligence but has symptoms of attention deficit hyperactivity disorder (ADHD). What is the first test that is indicated in her work-up for ADHD?

104) A 21-year-old woman has just delivered a term infant. She has had only one visit to her obstetrician, and that was at about 6 weeks of pregnancy. She provides her laboratory results from that visit. The delivered infant is microcephalic, has cataracts, a heart murmur, and hepatosplenomegaly. Your further evaluation of the child demonstrates thrombocytopenia, mild hemolytic anemia, and, on the echocardiogram, patent ductus arteriosus and peripheral pulmonary artery stenosis. Which of the following maternal laboratory tests done at 6 weeks gestation is likely to explain the findings in this child?

105) A 4-year-old boy from India presents with weakness. His parents note that he has been looking increasingly pale. Hemoglobin electrophoresis demonstrates an abnormal hemoglobin species. Genetic analysis indicates that the patient has the substitution of a valine for a glutamine in the sixth position of the betahemoglobin chain. Which of the following will most likely be seen on his blood smear?

106) A concerned mother brings her 2-month-old daughter to the clinic because of constipation. The mother had appropriate prenatal care but decided to deliver her child at home with the help of a midwife. The child has not received any medical attention since birth. Examination reveals jaundice, an umbilical hernia, and poor muscle tone. Which of the following is the most appropriate diagnostic study?

107) A one-month-old infant is born with craniofacial anomalies. Further evaluation reveals a cognitive impairment, a 22q 11 microdeletion in his chromosomes, and a heart condition with a right-to-left shunt. The infant subsequently undergoes heart surgery. The surgeon notes that the patient's thymus is absent. The anesthesiologist observes prolonged QT intervals in the patient's ECG. What is the most important parameter that should be monitored throughout this surgery?

109) A 14-year-old girl is brought to the office by her mother for the evaluation of leg muscle fatigability while climbing the stairs. She has occasional headaches. She was diagnosed (via karyotyping) with Turner's syndrome two years ago. Her blood pressure is 165/95 mm Hg on the right arm, and 161/95 mm Hg on the left arm. Her heart rate is 85/min. The physical examination reveals no secondary sexual characteristics. Her chest is broad. The point of maximal apical impulse is displaced to the left and increased in intensity. A mild, continuous murmur is heard all over the chest. The lungs are clear. What is the most probable finding on her chest radiograph?

110) A 14-year-old male presents with a complaint of soreness, and weakness in his legs for the past day that has slowly spread from his calves to his thighs. He now complains of weakness in his trunk and arms. On examination he appears tired and lays on the examining table. His temperature is 37 C (98.6 F), pulse is 48/min, and respirations are 22/min. Both of his legs are diffusely tender. Deep tendon reflexes are absent in the lower extremities, and sensation is greatly diminished. Which of the following studies is essential for this patient's diagnosis?

113) A nurse notices that a 1-week-old, premature infant in the neonatal unit is experiencing migratory jerks of the extremities. She picks the infant up and can feel that the muscle jerks are continuing to happen, even when she holds an involved extremity still. After about 5 minutes, the jerking movements stop. Which of the following is the most appropriate first step in diagnosis?

114) A 7-year-old is brought to the office with sore throat, poor appetite, and malaise over the last 2 days. He has no cough, rhinorrhea, or nasal congestion. The boy takes no medications, has no known allergies, and his immunization are up to date. Temperature is 38.9 C, BP is 110/70 mmHg, pulse is 130/min, and respitations are 16/min. On examination, his tonsils are swollen and covered with thin, with exudates. Small, tender anterior cervical lymph nodes are palpated. What is the most appropriate next step in management of this patient?

115) A 12-year-old male child comes to the office after being referred for a medical evaluation. His schoolteacher says that he has a problem concentrating during class. He stares in space for a few seconds several times a day, and appears totally absorbed in his thoughts. He is not disruptive in class, but appears forgetful. There is no history of trauma, infection or problem at birth. On examination, the child is alert with stable vital signs. There is no loss of motor or sensory perceptioin. Which of the following can confirm the patient’s diagnosis?

116) Within 8 hours after birth, an infant has "excessive salivation." Physical examination reveals that she has an imperforate anus, with a small fistula to the vagina. A small, soft nasogastric tube is inserted, and the infant is taken to x-ray. The film shows the tube coiled back on itself in the upper chest, and a normal gas pattern in the gastrointestinal tract. There are no apparent abnormalities of the radius or the vertebral bodies. Which of the following is the most appropriate next step in management?

117) An 8-year-old girl is brought to the pediatrician's office for evaluation of new onset swelling around the eyes. Physical examination reveals periorbital, sacral, and pretibial edema; her blood pressure is 96/64 mm Hg. The rest other physical examination is normal. Which of the following is the most appropriate initial diagnostic study?

118) A 4-year-old child is observed to hold his eyelids open with his fingers and to close one eye periodically, especially in the evening. He has some trouble swallowing his food. He usually appears sad, although he laughs often enough. He can throw a ball, and he runs well. Which of the following is most likely to aid in the diagnosis?

120) A neonate is markedly edematous and dies 1 hour after birth. A diagnosis of hydrops fetalis is made after the hematocrit on cord blood is demonstrated to be 5%. The erythrocytes in a smear from the cord blood are markedly hypochromatic. The mother is Rh positive and is known to have alpha-thalassemia trait. The thalassemia status of the father is unknown. Alpha-thalassemia is the suspected cause of the infant's hydrops. Which of the following hemoglobins would most likely be markedly elevated in this infant's blood if this diagnosis were correct?

121) A 21-year-old woman presents to the emergency room in active labor. She has had no prenatal care, but her last menstrual period was approximately 9 months prior. Her membranes are artificially ruptured, yielding no amniotic fluid. She delivers an 1800-g (4-lb) term infant who develops significant respiratory distress immediately at birth. The first chest radiograph on this infant demonstrates hypoplastic lungs. After this infant is stabilized, which of the following is the most appropriate next step for this infant?

122) A 7-year-old girl was found in a routine health supervision visit to have bilateral breast tissue development. She also had long, pigmented hair over the labia majora. Her height and weight are both at the 80th percentile for her age. Which of the following is the most appropriate management?