Tuberculosis

Question 1

What are the ESSENTIAL INVESTIGATIONS for the diagnosis of Tuberculosis?

Answer 1

1) Sputum Microscopy and Culture

2) CXR

Question 2

What would you expect to see in the CXR of a POST-PRIMARY TB case?

Answer 2

1) Patchy Shadowing
2) Often in the Apices/Upper Zones ( > oxygenation)
3) Bilateral
4) Cavitation, if advanced
5) Calcification, if chronic or healed TB

Question 3

What FURTHER INVESTIGATIONS can be carried out for the diagnosis of TB?

Answer 3

1) CT Thorax
2) Bronchoscopy with Bronchoalveolar Lavage
3) Transbronchial Biopsy
4) Pleural Aspiration and Biopsy, if Pleural Effusion

Question 4

What are the TREATMENT REGIMENS for TB?

Answer 4

MULTIPLE DRUG THERAPY for 6 months

For 2 months:

Rifampicin
Isoniazid
Pyrazinamide
Ethambutol

For 4 months:

Rifampicin
Isoniazid

Question 5

What are the SIDE EFFECTS of TB treatments?

Answer 5

Rifampicin:
Orange urine, tears
Hepatitis

Isoniazid:
Hepatitis
Peripheral Neuropathy

Pyrazinamide:
Gout

Ethambutol:
Optic Neuropathy

Question 6

What are the PUBLIC HEALTH DUTIES of doctors when managing TB?

Answer 6

1) Legal requirement to NOTIFY ALL CASES
2) Screen close household contacts
3) If close contacts are infected, screen casual contacts, also

Question 7

Describe the IMPACT of TB in the UK:

Answer 7

Growing Problem since the mid-1980s

Most prevalent in areas with increased immigration, i.e. London

Question 8

Describe the Global Distribution of TB:

Answer 8

Second leading cause of death from Infectious Disease worldwide, behind Malaria

Most prevalent in the Developing World, i.e. Africa

High incidence rate among the Immunosuppressed, i.e. HIV +ve; Malnourished; Diabetics and the Elderly

Question 9

What are the PRIMARY ORGANISMS involved in the spread of TB?

Answer 9

1) Mycobacterium Tuberculosis

2) Mycobacterium Bovine

Question 10

Describe the HISTOLOGICAL characteristics of TB organisms:

Answer 10

Slow Proliferation

Aerobic, Acid-Fast Bacilli (ZN-stain)

Thick, Waxy Cell Wall

Resistant to Acids, Alkalis, etc

Question 11

What are the COMMON SYMPTOMS of PRIMARY TB?

Answer 11

Usually Asymptomatic

Can present with Fever and Malaise

Question 12

What is a COMMON CLINICAL PRESENTATION of PRIMARY TB?

Answer 12

Initial Granulomatous Lesion (Ghon Focus) + Local, Hilar Lymph Node = GHON COMPLEX

Caseous Necrosis of the tissue

May then Calcify and Fibrose

Scar tissue formation

Question 13

What are the THREE possible STAGES of the development of Primary TB?

Answer 13

Progressive Disease

Contained and Latent

Cleared and Cured

Question 14

What are the SIGNS of POST-PRIMARY TB?

Answer 14

Can be NO physical signs

Crackles
Bronchial Breathing, if advanced

Finger Clubbing - rare and only if chronically infected

Question 15

What are the SYMPTOMS of POST-PRIMARY TB?

Answer 15

May be ASYMPTOMATIC, initially

After several months:

Cough
Productive of Sputum
Haemoptysis
Pleuritic Chest Pain
Dyspnoea