Resp

Question 1

primary, secondary and miliary TB

Answer 1

primary: encapsulated in hilar lymph nodes, Ghon focus macrophages contain it
secondary: goes to apices of lungs
miliary: disseminated in bloodstream

Question 2

Secondary TB sites

Answer 2

Lungs (most common)
central nervous system (tuberculous meningitis - the most serious complication)
vertebral bodies (Pott’s disease)
cervical lymph nodes (scrofuloderma)
renal
gastrointestinal tract

Question 3

Systemic TB symptoms

Answer 3

night sweats
fever
weight loss

Question 4

Lung TB symptoms

Answer 4

Chronic cough productive of purulent sputum +/- haemoptysis.
Can get bronchiectasis, pneumonia and pleural effusions.

Question 5

CNS TB symptoms

Answer 5

TB meningitis or tuberculoma
Headache
Meningism
Focal neurological signs
Decreased consciousness

Question 6

Genitourinary TB symptoms

Answer 6

Second most affected organ system outside of the lungs.
Causes ‘sterile’ pyuria, kidney pathology, abscesses, salpingitis and infertility, epididymo-orchitis.

Question 7

MSK TB symptoms

Answer 7

Arthritis
Osteomyelitis
Psoas abscess
Pott’s Disease of the Spine.

Question 8

skin TB symptoms

Answer 8

erythema nodosum

Question 9

TB investigations

Answer 9

CXR - upper lobe cavitation is the classical finding of reactivated TB
bilateral hilar lymphadenopathy
Sputum samples for culture and sensitivity testing (at least three needed - may need to consider lavage or sputum induction if cannot produce)
Samples from non-pulmonary sites: may need biopsy and needle aspiration
Samples are stained with Ziehl-Neelsen or Auramine staining for direct microscopy

Question 10

IGRA test

Answer 10

Interferon-Gamma Release Assays (IGRAs) - cannot tell difference between latent or active TB, and not useful in very young or immunosuppressed patients.
Results are obtained rapidly, however, and are not affected by prior BCG.
may be used after mantoux

Question 11

Mantoux test

Answer 11

Mantoux test - usually offered to contacts of infected patients.
Positive in those who have had the BCG vaccine.

Question 12

TB management

Answer 12

rifampicin, Isoniazid, pyrazinamide and ethambutol for 2 months,
then rifampicin and Isoniazid for a further 4 months.
Extended duration in TB meningitis, pericarditis, and spinal TB - meningitis 12 months + steroids

Question 13

Rifamipicin s/e

Answer 13

Liver toxicity
Hepatic enzyme (p450) inducer
Turns bodily fluids red/orange colour.

Question 14

Isoniazid s/e

Answer 14

Peripheral neuropathy (pyridoxine VB6 is given to prevent this)
hepatitis
agranulocytosis
liver enzyme inhibitor

Question 15

Pyrazinamide s/e

Answer 15

hyperuricaemia causing gout
arthralgia, myalgia
hepatitis

Question 16

Ethambutol s/e

Answer 16

Visual disturbance (colour blindness, loss of acuity etc.)
Avoid in chronic kidney disease - adjust dose

Question 17

Main screening test for TB

Answer 17

Mantoux test

Question 18

Which sputum sample needs 3 samples and is stained for acid fast bacilli

Answer 18

Sputum smear
(ziehl neilson stain)

Question 19

the gold standard investigation for TB
more sensitive than a sputum smear and nucleic acid amplification tests
can assess drug sensitivities
can take 1-3 weeks (if using liquid media, longer if solid media)

Answer 19

sputum culture

Question 20

TB test:
allows rapid diagnosis (within 24-48 hours)
more sensitive than smear but less sensitive than culture

Answer 20

Nucleic acid amplification tests (NAAT)

Question 21

Latent TB treatment

Answer 21

3 months of isoniazid (with pyridoxine) and rifampicin OR 6 months of isoniazid (with pyridoxine)