Pulmonary TB

Question 1

Definition?

Answer 1

Pulmonary tuberculosis (TB) is an infectious disease caused byMycobacterium tuberculosis.

Question 2

RF?

Answer 2

• Infection
• Birth in endemic country
• HIV
• Immunosuppressive meds
• Silicosis
Apical fibrosis

Question 3

ddx?

Answer 3

• COVID-19-fever, cough, loss of taste and smell
• CAP-crackles and dyspnoea
• Lung cancer-constitutionals
• Non-TB mycobacteria-cavitation
• Fungal infection-travel
Sarcoidosis-intrathoracic lymphadenopathy and arthralgias

Question 4

epidemiology?

Answer 4

Age:
Sex:
Ethnicity: Asia, Africa, Western Pacific

Question 5

Aetiology?

Answer 5

M.TB/mycobacterium

Question 6

CP?

Answer 6

• RFs
• Cough
• Fever
• Anorexia
• Weight loss
• Malaise
• Night sweats
• Pleuritic chest pain
• Haemoptysis
Crackles, bronchial breath sounds, or amphoric breath sounds (distant hollow breath sounds heard over cavities).

Question 7

Pathophysiology?

Answer 7

• M.TB are rod shaped, and needs oxygen as strict aerobes
• Waxy cell wall from mycolic acid that make them survive even after acidic environments
• Resists weak disinfections and survives on dry surfaces
• Transmitted via inhalation
• TB avoids mucociliary elevators
• Alveolar macrophages phagocytose M.TB but release protein so lysozyme cannot bind so it isn’t broken down and in fact proliferates
• After 3 wks- cell mediated immunity-create granulomas-tissue inside middle dies causes caseous necrosis-Ghon focus
• Ghon complex-ghon focus and caseating necrosis in LNs-subpleural and in lower lobes
• Ranke complex-fibrosis and calcification of Ghon complex
• TB can be killed off are dormant and walled off and can be reactivated in immunosuppression to spread to upper lobes where more oxygen is
Memory T cells release cytokines more caseating necrosis and cavitates and disseminates to the lungs (bronchopneumonia) or the vascular system causing systemic miliary TB

Question 8

signs pulmonary TB?

Answer 8

• kidneys-pyuria
	• Meningitis
	• Lumbar vertebrae-pott disease
	• Adrenal glands-Addisons disease
	• Liver-hep
Cervical LNs-scrophula

Question 9

Investigations first line?

Answer 9

• CXR-fibronodular opacities in lobes, lymphadenopathy and or pleural effusion
• Sputum acid-fast bacilli smear-M.TB
• Sputum culture-gowth of M.TB-Ziehl Neesen stain-red vibrae
• FBC-raised WCC, low Hb
• NCA-positive for M.TB
Purified protein derivative intradermal skin test

Question 10

I-Second line onwards?

Answer 10

• Bronchoscopy
• Empirical treatment
• CT
• Specific microbe assays

Question 11

m-latent?

Answer 11

6 or 9 months of daily isoniazid, 3 months of weekly rifapentine plus isoniazid, or 3 months of daily isoniazid plus rifampicin.One month of daily rifapentine plus isoniazid or 4 months of daily rifampicin are alternative regimens

Question 12

m-acute?

Answer 12

• Initial Phase-
  
  • first-line treatment is isoniazid, rifampicin, pyrazinamide, and ethambutol
  • Directly observed therapy or self-administered
• Continuation Phase
• The continuation phase is 18 weeks in duration and medication is given after completion of the initial phase

• Isoniazid resistance
Multidrug resistance

Question 13

m if acute HIV?

Answer 13

• Intial phase
• Continuation phase
• Anti-TB therapy
• Standardised or individualised long term regimen
• Surgery
• Intensive and continuation regimen
• Surgery
Consult if pregnant or hepatic dysfunction

Question 14

prognosis?

Answer 14

RFs

few complications if treated well

Question 15

complications?

Answer 15

• Transmission
• IRIS
• ARDS
• Pneumothorax
• Empyema
• Bronchiectasis
• Lung destruction
• Right middle lobe syndrome
haemoptysis

Question 16

indications for vaccine?

Answer 16

• are born in areas of the UKwhere the rates of TB are high
• havea parent or grandparent who was born in a country wherethere’sa highrate ofTB
• Work with animals, fluids, refugees, prisoners and homeless people and healthcare workers
• Travelling to endemic areas/infected people

Question 17

presentation of non-pulmonary TB?

Answer 17

• RF’s
  
  • Enlarged LN
  • Pleuritic chest pain
  • Skeletal pain
  • Urinary symptoms
  • Abdominal swelling
  • Abdominal pain
  • Headache

Question 18

ethical and legal consequences of TB therapy?

Answer 18

• Ethical-choices, wider effect on communities,

Legal-sanctions, health education, duty of HCP

Question 19

DOT?

Answer 19

• A method of drug administration in which a health care professional watches as a person takes each dose of a medication.
Directly observed therapy (DOT) is used to ensure the person receives and takes all medications as prescribed and to monitor response to treatment.

Question 20

multi-drug resistant TB?

Answer 20

• Resistance to isoniazid and rifampicin
• Can take up to 12 months to treat
Mutations or re-exposure to same /diff RF/causative agent

Question 21

Screening?

Answer 21

Screening of risk groups allows the burden of disease in countries to be lowered

Question 22

Mantoux test?

Answer 22

• Purified protein derivative of M.TB injected and measure mm of wheal/induration
Delayed type 4 hypersensitivity reaction via TH1 cells

Question 23

Notification?

Answer 23

• Can result in outbreaks

Done via Enhanced TB Surveillance -paper or online forma

Question 24

Traced?

Answer 24

• Household contacts or other close contacts
• In occupational exposures-current and former workers should be contacted
Immunocompromised contacts