INFECTIVITY

LEGIONELLA

Q.Which of the following organisms, if found on a sputum culture, definitely indicates infection?
A. Chlamydia pneumoniae
B. Pneumococcus
C. Haemophilus influenzae
D. Legionella pneumophila
E. Moraxella

D. Legionella is not known to be a colonizer; if it is found on culture, it should be treated. While Mycoplasma and Chlamydia cultures are rarely sent, these organisms can be found in asymptomatic subjects, so their mere presence does not require treatment. Moraxella, Haemophilus, and Pneumococcus can also be colonizers in asymptomatic patients. However, they should be treated in a patient with clinical signs of pneumonia and one of these organisms

predominating in a sputum Gram stain and culture

ATD

ATD

Q.Which of the following drugs is a first-line agent against TB?
A. Streptomycin
B. Pyrazinamide
C. Para-aminosalicylic acid (PAS)
D. Levofloxacin
E. Cycloserine

Ans:B.

Pyrazinamide is one of the four first-line TB drugs. The other listed drugs are second line because of decreased or less proven efficacy, the necessity for parenteral administration

(streptomycin), serious side effects (PAS and cycloserine), or cost and reservation for other uses (levofloxacin).

RIFAMPICIN

ORANGE DISCOLOURATION

Q. Which of the following side effects occurs commonly with the administration of rifampin for N. meningitides chemoprophylaxis?
A. Liver failure
B. Renal failure
C. Orange discoloration of secretions
D. Anemia
E. Leukopenia

Ans: C.

Rifampin will turn all of an individual’s secretions, such as urine, sweat, tears, and stool, an orange color. Contact lenses can be permanently stained with this orange discoloration. This side

effect is a source of great consternation to individuals who are not warned of its possibility.

IMAGE DIAGNOSIS Q1

Q.. What is the diagnosis in this diabetic woman?

(a) Toxic megacolon

(b) Emphysematous cholecystitis

(c) Ileus

(d) Diverticular disease

(e) Volvulus

Ans:B.

 The diagnosis here is emphysematous cholecystitis because air can be seen in the wall of the gallbladder. The condition, due to infection, most commonly occurs in elderly female diabetics and is usually caused by coliforms.

Causes of gas in the biliary tree

Within the bile ducts

1.      Incompetence of the sphincter of Oddi following sphincterotomy, passage of a

gallstone or in the elderly (‘patulous sphincter’)

2.      Postoperative cholecystectomy or choledochoenterostomy

3.      Spontaneous biliary fistula due to passage of gallstone from gallbladder to bowel,

duodenal ulcer perforating into common bile duct, tumour or malignancy

Within the gallbladder-

• Emphysematous cholecystitis