Multi Drug Resistant Tuberculosis (MDR)
Multi Drug Resistant Tuberculosis (MDR)
Multi Drug Resistant Tuberculosis (MDR)
Types Of Resistance
Primary drug resistance: Presence of resistance to anti TB drugs in a patient who has not received anti TB drugs in the past Acquired drug resistance: Resistance to anti TB drugs in a patient during the course or after treatment with ATT
Natural drug resistance: Strains of tubercular bacilli naturally resistant to anti TB drugs. eg: M. Bovis is resistant to PZA Multi drug resistance: Development of resistance to both INH and Rifampicin with or without resistance to other anti TB drugs
Diagnosis of MDR
Detailed treatment history including history of contact Progressive radiological worsening Absence of clinical improvement in spite of optimal ATT Persistence of sputum positivity Fall and rise phenomenon
1. Conventional culture
2. Rapid culture- BACTEC
Complications of TB
Haemoptysis:
Causes are Rupture of Rasmussen aneurysm Erosion of blood vessel by broncholith Aspergilloma in a cavity Post tubercular bronchiectasis Rupture of fibrotic bands Anastamosis between bronchial and pulmonary artery
Complications of TB
Pleural complications: PLEF, empyemas, pneumothorax, bronchopleural fistula Bronchiectasis TB laryngitis Open negative syndrome Secondary bronchitis Cor pulmonale Respiratory failure Amyloidosis Disseminated Koch's Scar carcinoma
TB & HIV
HIV increases susceptibility to infection with tuberculosis by 10 folds Progression of TB more rapid in HIV and vice versa Higher incidence of extra pulmonary TB in HIV patients Higher risk of intolerance to ATT, relapse and MDR Poses diagnostic difficulties due to atypical features and smear negativity
BCG VACCINE
Live attenuated vaccine Does not protect against infection, but efficacy in preventing disease varies from 20-80% Route intradermally Adverse effect: keloids, ulcers, lymphadenitis, disseminated infection
tuberculosis infection
Intradermal administration of 5 units of PPD Induration > 10 mm considered positive test Induration > 5mm positive in those with HIV, close contact with sputum positive cases, those with XRC changes Test is neither sensitive nor specific False negative occurs in HIV positive, on steroids etc
Chemo Prophylaxis
1. 2. 3. Used to prevent the development of the disease Drug used is INH at dose of 5-10 mg / kg / day for 6 months Indicated in Mantoux > 10mm with risk factors like DM, steroid therapy, malignancies Mantoux > 5mm with HIV positive, contact with infectious person, lesion on chest X-ray Mantoux > 15mm with age < 35 yrs with no risk factors