Extrapulmonary tuberculosis

Extrapulmonary tuberculosis (TB) refers to the hematogenous spread of Mycobacterium tuberculosis.

Pathology

Extrapulmonary tuberculosis can occur as a primary form of the disease, i.e. direct infection of an extrapulmonary organ without the presence of primary pulmonary tuberculosis or it can occur as a result of the spread of primary pulmonary tuberculosis. 

It appears classically as tuberculous granulomata (tuberculomas) within the affected organs. However, certain forms of the disease exist manifesting with specific findings:

• CNS
  • tuberculous meningitis
  • tuberculous pachymeningitis
  • intracranial tuberculous granuloma (tuberculoma)
  • focal tuberculous cerebritis
  • intracranial tuberculous abscess
  • tuberculous rhombencephalitis
  • tuberculous encephalopathy
• head and neck
  • tuberculous otomastoiditis
  • laryngeal tuberculosis
• musculoskeletal
  • tuberculous spondylitis (Pott disease)
  • tuberculous osteomyelitis
  • tuberculous arthropathy
• abdominal tuberculosis
  • gastrointestinal tuberculosis
    • esophageal tuberculosis
    • gastric tuberculosis
    • duodenal tuberculosis
    • jejunal and ileal tuberculosis
    • ileocecal tuberculosis
    • colorectal tuberculosis
  • tuberculous peritonitis
  • tubercular lymphadenopathy
  • visceral tuberculosis
    • hepatic tuberculosis
    • gallbladder tuberculosis
    • pancreatic tuberculosis
    • splenic tuberculosis
    • genitourinary tuberculosis
      • renal tuberculosis
      • bladder and ureteric tuberculosis
      • prostatic tuberculosis
      • scrotal tuberculosis (testes, epididymis, seminal vesicles, ductus (vas) deferens)
      • tuberculous pelvic inflammatory disease (female)
        • tuberculosis of the Fallopian tube​

Radiographic features

Widely variable dependent on the site of involvement. It is best to refer to site-specific articles.

As tuberculous organ infection can mimic malignant disease recent studies have reported the usefulness of ¹⁸FDG PET-CT in evaluating and following up patients in whom the diagnosis is in doubt ⁴.