Basic science Q 101 to Q 200

101 Which one of the following viruses is the leading cause of congenital malformations?

102 Orchitis, which may cause sterility, is a possible manifestation of which of the following?

103 Which of the following is a leading cause of pneumonia primarily in infants?

104 Which of the following causes a fatal encephalitis for which a vaccine is available?

105 Traditional vaccination for the common cold is virtually impossible because there are multiple serotypes of which one of the following viruses?

106 Which of the following is available and effective for hepatitis A?

107 Patients should be vaccinated annually for influenza with which of the following vaccines?

108 The vaccine for measles is best characterized as a

109 Which one of the following would be the treatment of choice for HSV infection?

110 Which of the following best describes the presently available vaccine for hepatitis B?

111 Chicken pox is a common disease of childhood. It is caused by which of the following viruses?

112 Excluding influenza, which one of the following viruses is a common cause of acute respiratory disease?

113 A vaccine is available for one of the most common causes of infantile gastroenteritis. However, it has recently been recalled. The virus is

114 A child has mononucleosis-like symptoms yet the test for mononucleosis and the EBV titers are negative. One of the causes of heterophile- negative mononucleosis is

116 Lethargy, malaise, and fatigue are observed in a patient 2 weeks after eating raw hamburger at a restaurant. The most likely infectious cause is

117 This virus may be detected by the polymerase chain reaction (PCR) in a variety of cells of patients with nasopharyngeal carcinoma.

118 What the most appropriate specimen is for the detection of Human papillomavirus

119 What the most appropriate specimen is for the detection of Cytomegalovirus

120 What the most appropriate specimen is for the detection of Enterovirus

121 What the most appropriate specimen is for the detection of Varicella-zoster virus (VZV)

122 What the most appropriate specimen is for the detection of Adenovirus 40/41

124 Which of the following is the most common cause of pediatric gastroenteritis? It is difficult to grow in cell culture but can be detected easily by immunologic methods (ELISA).

125 Which of the following is a common cause of epidemic gastroenteritis, particularly aboard cruise ships and in summer camps? It may be detected by ELISA methods or electron microscopy.

126 Which of the following is a cause of mild gastroenteritis? It can be transmitted by the fecal-oral route but not by food consumption.

127 IgM antibody to the viral particle is the method of choice for laboratory diagnosis of which one of the following hepatitis viruses?

128 This virus belongs to the family of flaviviruses and its reservoir is strictly human. Transmission is blood-borne so the blood supply is routinely screened for this virus.

129 Vaccination for this hepatic disease is with viral surface antigen and usually provides immunity.

130 This hepatitis virus is a calicivirus. The reservoir is in pigs, and humans acquire it via the fecal-oral route.

131 This hepatitis virus is a defective virus in that it cannot replicate independently without the presence of hepatitis B virus.

132 This virus is the leading cause of bronchiolitis and community- acquired pneumonia in infants.

133 This is a double-stranded DNA virus. It is responsible for 15% of pediatric respiratory infections and 10 to 15% of acute diarrhea in children.

135 A 21-year-old college student complained of malaise, low-grade fever, and a harsh cough, but not of muscle aches and pains. An x-ray revealed a diffuseinterstitial pneumonia in the left lobes of the lung. The WBC count was normal. The student has been ill for a week.Based on the information given, the most likely diagnosis is

136 Based on the information given, which of the following laboratory tests would most rapidly assist you in making the diagnosis?

137 Pathogenic mechanisms involved in tuberculosis can be primarily attributed to which of the following?

138 Cholera is a toxicogenic dysenteric disease common in many parts of the world. In the treatment of patients who have cholera, the use of a drug that inhibits adenylcyclase would be expected to

139 Symptoms of C. Botulinum food poisoning include double vision, inability to speak, and respiratory paralysis. These symptoms are consistent with

140 In people who have sickle cell anemia, osteomyelitis usually is associated with which of the following organisms?

141 The treatment of choice for a patient with C. Jejuni enterocolitis is

143 Culture of the menstrual fluid in the case cited would most likely reveal a predominance of

144 The incidence of H. Influenzae meningitis in the general population is less than 1%. If during an epidemic the incidence rose to 3%, the negative predictive value of the LA test would

145 A 2-year-old infant is brought to the emergency room with hemolytic uremic syndrome and thrombocytopenia. Which one of the following bacteria would most likely be isolated from a stool specimen?

146 E. Coli causes disease by a variety of different methods. Which one of the following E. Coli types is characterized by the presence of LT (heat-labile) and ST (heat-stable) proteins?

147 Human plague can be bubonic or pneumonic. The primary epidemiologic difference between the two clinical forms of plague is

149 The most common portal of entry for C. tetani, the cause of tetanus, is the

150 The most common way in which tuberculosis is acquired is via the

152 A person who contracts gonorrhea is most likely to have acquired it via the

153 The antibiotic of choice for pneumococcal pneumonia is

154 The antibiotic of choice for streptococcal pharyngitis is

155 The therapy of choice for pseudomembranous enterocolitis is

156 V. cholerae, the causative agent of cholera, is best described as

157 Y. enterocolitica, formerly a Pasteurella, is best described by which of the following statements?

158 To isolate specific bacteria from clinical specimens, it is necessary to use a variety of artificial media, some of which is selective, others of which are nonselective. N. Gonorrhoeae is a fastidious pathogen and found in sites often con- taminated with normal flora. The best medium for isolation is

159 V. cholerae, the causative agent of cholera, is best isolated using

160 M. Tuberculosis can be found in the sputum of patients with tuberculosis. After digestion of the sputum, isolation is best accomplished using

161 C. Diphtheriae may be difficult to isolate from the nasopharynx with- out the use of special media. The medium of choice is

162 S. Aureus has a distinctive appearance on which one of the following media?

163 In order to recognize abnormal bacteria, it is necessary to know which bacteria are predominant normal flora of certain body sites.

164 Which of the following is the most prevalent microorganism in the vagina that may also be protective?

165 Influenza can be treated; therefore, specific detection of the virus becomes much more important. Which of the following would be best for detection of influenza?

166 A bacterium is examined and is found to lack superoxide dismutase, catalase, and peroxidase. Which of the following statements best describes this bacterium?

168 Ideally, an antibiotic should focus on a microbial target not found in mammalian cells. By this standard, which of the following antibiotic agents would be expected to be most toxic to humans?

169 A broad-spectrum antibiotic in the general class of thienamycins is

170 Third-generation cephalosporin with good activity against Borrelia burgdorferi is

171 Broad-spectrum penicillin with antipseudomonas activity is

172 Third-generation cephalosporin with primary activity againstPseudomonas aeruginosa is

173 Quinolone antibiotic with broad Gram-negative and Gram-positive activity is

174 Mycoplasmas differ from chlamydiae in that they are

175 Which of the following mycoplasmas has been implicated as a cause of nongonococcal urethritis (NGU)?

176 C. Trachomatis can be distinguished from C. Psittaci by which of the following criteria?

177 Trachoma is one of the leading causes of blindness. Which of the fol- lowing best typifies the disease?

178 Which one of the following organisms causes primary atypical pneumonia in humans?

179 Which one of the following organisms is associated with nongonococcal urethritis in humans?

180 Which one of the following organisms normally inhabits the healthy human oral cavity?

181 Which one of the following organisms normally inhabits the female genital tract but may cause acute respiratory illness?

182 Inhalation of fungal spores can cause primary lung infections. Of the following organisms, which one is most likely to be associated with this mode of transmission?

183 An immunocompromised patient is suspected of having an infection with A. fumigatus. Which of the clinical conditions is most likely to occur?

184 The diagnostic characteristics of Plasmodium falciparum are best described by which one of the following statements?

185 The life cycle of this parasite consists of two stages: the cyst and the trophozoite, as shown in the figure below. The most likely identification of this organism is

186 Human infection with the beef tapeworm, Taenia saginata, usually is less serious than infection with the pork tapeworm, T. solium, because

187 A survey of 100 healthy adults reveals that 80% have IgG antibodies to Toxoplasma. Which one of the following statements would help to explain this finding?

189 Trypanosoma cruzi initially penetrates through the mucous mem branes on the skin and then multiplies in a lesion known as a chagoma. In the chronic stage of the disease, the main lesions are often observed in the

190 A woman, recently returned from Africa, complains of having paroxysmal attacks of chills, fever, and sweating; these attacks last a day or two at a time and recur every 36 to 48 h. Examination of a stained blood specimen reveals ring-like and crescent-like forms within red blood cells. The infecting organism most likely is

192 Malaria is a significant worldwide public health problem. Which one of the following control methods for malaria is currently effective?

193 Scabies is caused by a small mite that burrows into the skin. The disease is best described by which one of the following statements?

194 Amebae that are parasitic in humans are found in the oral cavity and the intestinal tract. Which one of the following statements best describes these intestinal amebae?

195 Schistosomiasis is a disease characterized by granulomatous reac- tions to the ova or to products of the parasite at the place of oviposition. Clinical manifestations include which one of the following?

196 Flukes (trematodes) have a great impact on worldwide public health, causing both morbidity and mortality. Which of the following organisms penetrates skin, is endemic in Africa and Latin America, and has a large lateral spine on its eggs?

197 Which of the following organisms may be ingested with raw fish, affects the liver, and has an operculated egg?

198 Which of the following organisms penetrates skin, is endemic in Asia, and has a small lateral spine on its eggs?

199 Which of the following organisms penetrates skin, is endemic in Africa and the Middle East, has large terminal spines on its eggs, and is found in urine samples?

200 Which of the following organisms penetrates skin, is endemic in Africa and the Middle East, has large terminal spines on its eggs, and is found in urine samples?