Extrapulmonary tuberculosis

Extrapulmonary tuberculosis (EPTB) now represents about half of all diagnosed cases of TB in the UK and is seen increasingly in patients with immunosuppression or HIV. It is usually caused by reactivation of latent infection and may cause disease at almost any site in the body. Most common sites include lymph nodes (19%), pleura (7%), gastrointestinal tract (4%), bone (6%), CNS (3%) and genitourinary system (1%). Its manifestations depend on the site of disease, making diagnosis challenging as EPTB may mimic many other diseases. Hence TB should be considered in the differential diagnosis of any sick patient. A diagnosis of EPTB should trigger a search for concomitant pulmonary disease, which has implications for infectivity, and an HIV test (as with any TB diagnosis). Obtaining appropriate samples for microbiological diagnosis is vital for effective management, especially as drug-resistance becomes more common. Treatment is generally with standard quadruple therapy for 6 months (extended in TB meningitis); adjunctive steroid therapy is of proven value in TB pericarditis and meningitis.