Question 1: Which one of the following microorganisms uses antigenic variation as a major means of evading host-defences ?
A) Streptococcus pneumoniae
B) Borrelia recurrentis
C) Mycobacterium tuberculosis
D) Listeria monocytogenes
Answer:
D
Question 2: Which one of the following statements is correct regarding chronic granulomatous disease?
A) It is an autosomal dominant disease
B) It is characterized by abnormal bacterial phagocytosis
C) Recurrent streptococcal infections are usual in this disease
D) Nitroblue tetrazolium test is useful for screening
Answer:
B
Question 3: Humoral immunodeficiency is suspected in a patient and he is under investigation. Which of the following infections would not be consistent with the diagnosis ?
A) Giardiasis
B) Pneumocystis carinii pneumonia
C) Recurrent sinusitis
D) Recurrent subcutaneous abscesses
Answer:
B
Question 4: All of the following statements are true regarding Staphylococci except ?
A) A majority of infections caused by coagulase-negative Staphylococci are due to Staphylococcus epidermidis
B) ß-lactamase production in Staphylococci is under plasmid control
C) Expression of methicillin resistance in Staphylococcus aureus increases when it is incubated at 37°C on blood agar
D) Methicillin resistance in Staphylococcus aureus is independent of ß-lactamase production
Answer:
Question 5: A 15 year old girl was admitted to the infectious disease hospital with a provisional diagnosis of rabies. The most suitable clinical sample that can confirm the antemortem diagnosis is ?
A) Serum for anti-rabies IgG antibody
B) Corneal impression smear for immunofluorescence stain
C) CSF sample for viral culture
D) Giemsa stain on smear prepared from salivary secretions
Answer:
D
Question 6: In a completely and adequately immunized child against Diphtheria, the throat swab was collected. It showed the presence of Corynaebacterium diphtheriae like organisms on Albert staining. These organisms can have one of the following properties on further laboratory processing ?
A) It can grow on Potassium tellurite medium
B) It would show a positive Elek’s gel precipitation test
C) It can be pathogenic to experimental guinea pigs
D) It can produce cytotoxicity in tissue cultures
Answer:
Question 7: A 35 year old patient complains of abdominal cramps along with profuse diarrhea. The treating physician wants to process the stool specimen for isolation of Campylobacter jejuni. Which of the following is the method of choice for the culture of stool ?
A) Culture of TCBS medium incubated at 37°C under aerobic conditions
B) Culture on Skirrow’s medium incubated at 42°C under micro-aerophilic conditions
C) Culture on Mackconkey’s medium incubated at 42°C under anaerobic conditions
D) Culture on Wilson and Blair’s medium incubated at 37°C under microaerophilic conditions
Answer:
B
Question 8: All of the following are correct regarding Legionellae except ?
A) Legionellae can be grown on complex media
B) Legionella pneumophila serogroup 1 is the most common serogroup isolated from humans
C) Legionellae are communicable from infected patients to others
D) Legionella pneumophila is not effectively killed by polymorphonuclear leukocytes
Answer:
Question 9: The operating temperature in an ethylene oxide sterilization during a warm cycle is ?
A) 20-35 °C
B) 49-63 °C
C) 68-88 °C
D) 92-110 °C
Answer:
Question 10: Ebstein Barr virus is associated with ?