Infectious Disease

Tuberculosis

A chronic Mycobacterium tuberculosis complex infection that may remain latent or reactivate as active pulmonary or extrapulmonary disease, requiring microbiological diagnosis, multi-drug treatment and public-health contact tracing.

Definition

Tuberculosis is infection with Mycobacterium tuberculosis complex. Infection may be latent, with immune containment and no symptoms or transmission, or active, with disease in the lungs or another organ and potential transmission when the airway or larynx is involved.

First principles

Latent infection is immune containment, not eradication

Mycobacterium tuberculosis complex is inhaled as airborne droplet nuclei and may persist within granulomas after the initial immune response. Latent TB infection causes no symptoms and is not transmissible, but viable organisms can reactivate when cell-mediated immunity is weakened by HIV, immunosuppression, diabetes, malnutrition, age or other factors.

You’ve reached the end of the preview

The rest of this extended textbook page is part of full access. Create a free account to read the sample topics in full and try sample questions, then upgrade to unlock every high-yield and extended page, plus the complete question bank.

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.