TB Flashcards
What are the common causative organisms?
Mycobacterium tuberculosis
Mycobacterium bovii
Mycobacterium africanum
What is primary TB?
Spread by droplets and engulfed by macropahges
Where does primary TB tend to effect?
Hilum
What is secondary TB?
Reactivation of TB due to immune impairment
Where does secondary TB tend to effect?
Apices
What is miliary TB?
Occurs when primary infection is not contained and spreads to bloodstream
What are risk factors for TB?
Contact with TB Foreign travel Immunosuppressed IV drug users Homeless
What are the symptoms of respiratory TB?
B symptoms Cough SOB Haemopytsis Malaise
What are symptoms of non-respiratory TB?
Erythema nodosum
Meningitis symtpms
Lymphadenopathy
Bone pain
How do you investigate suspected TB?
Sputum culture - acid fast bacilli
Bloods
- quantiferon gold
- blood borne virus screen
CXR
CT chest
What stain do you use for TB?
Ziehl-Neelsen
What medium is TB sputum cultured on?
Lowenstein-Jensen slope
What are the CXR findings in TB?
Consolidation
Cavitating lesion
What is the treatment for pulmonary TB?
Rifampicin 6/12
Isoniazid 6/12
Pyrazinamide 2/12
Ethambutol 2/12
What is the treatment for TB meningitis?
Rifampicin 12/12
Isoniazid 12/12
Pyrazinamide 2/12
Ethambutol 2/12
What are the side effects of rifampicin?
Hepatitis
Orange secretions
What are the side effects of isoniazid?
Hepatitis
Peripheral neuropathy
Rashes
What are the side effects of ethambutol?
Optic neuritis
What are the side effects of Pyrazinamide?
Hepatitis
Arthralgia
Rashes
What is MDR TB?
Multi drug resistant TB
- resistant to more than one drug
What is XDR TB?
Extensively drug resistant TB
- resistant to more than 3 drugs
Is TB a notifiable disease?
Yes
What TB prophylaxis is available?
BCG
Isoniazid
When is prophylaxis indicated?
HIV
Recent exposure to TB
No BCG + mantoux >5mm
BCG + mantoux >10mm
What is the mantoux test?
Injection of dilutions of TB antigen under skin
>10mm = postive <5mm = negative
