TB

Question 1

Disseminated vs miliary TB?

Answer 1

(call in the military when the situation is severe)

Question 2

Rifampicin SEs?

Answer 2

red/orange urine and tears

potent cytochrome P450 inducer (reduced effectiveness of the pill)

“red-an-orange-pissin”

Question 3

Isoniazid SE?

Answer 3

peripheral neuropathy

“I’m-so-numb-azid”

Question 4

Pyrazinamide SE?

Answer 4

hyperuricaemia > gout.

Question 5

Ethambutol SE?

Answer 5

colour blindness and reduced visual acuity

“eye-thambutol”

Question 6

what should be co-prescribed with Isoniazid and why?

Answer 6

Pyridoxine (vitamin B6) - to reduce the risk of peripheral neuropathy

Question 7

Treatment of acute pulmonary TB?

Answer 7

RIPE 2 months

RI further 4 months

Question 8

Why is TB difficult to diagnose?

Answer 8

bacteria slow growing in culture

can’t be stained with traditional gram stains (waxy coat)> ‘acid fast’

Question 9

Tests for immune response to TB?

Answer 9

Mantoux

Interferon-gamma release assays

Question 10

Mantoux test

1) involves?
2) shows?

Answer 10

1) intradermal tuberculin injection > induration >5mm = positive
2) previous immune response to TB (vaccination, latent or active TB)

Question 11

IGRA

1) involves?
2) shows?

Answer 11

1) blood sample mixed with TB antigens > if they’ve had previous contact with TB the WBCs release interferon gamma
2) asymptomatic but positive mantoux > latent TB

Question 12

CXR

1) primary
2) reactivated
3) disseminated

Answer 12

1) patchy consolidation, pleural effusions and hilar lymphadenopathy
2) patchy/ nodular consolidation with cavitation typically in the upper zones
3) uniformly distributed ‘millet seeds’ throughout the lung fields

Question 13

Diagnosis of active TB

1) imaging
2) sputum ___ (rapid and inexpensive)
3) gold standard?
4) for rapid diagnosis?

Answer 13

1) CXR (b/l hilar lymphadenopathy, patchy consoliation)
2) sputum smear: 3 specimens stains for acid-fast bacilli (ZN stain)
3) Sputum culture: can assess sensitivities but takes 1-3 weeks
4) NAAT. Diagnosis in 24-48 hours.

Question 14

Vaccine

1) name
2) type
3) screening test first
4) contraindications

Answer 14

1) BCG
2) live attenuated
3) tuberculin skin test
4) previous BCG, history of TB, HIV, pregnancy, + tuberculin skin test

Question 15

BCG vaccine is not given to anyone over ___, as there’s no evidence that is works for people in this age group

Answer 15

35