Tuberculosis Clinical Presentation and Differential Diagnosis

Active tuberculosis (TB) disease presents with a variety of symptoms and signs. Mycobacterium tuberculosis (MTB) can affect multiple organs; within this chapter we review common symptoms and signs of active TB in the lung and extra-pulmonary sites. The sites of disease explored include: pulmonary infections, lymph node disease and central nervous system disease amongst others. Possible differential diagnoses to be considered are discussed within each organ, though often there may be overlap in the clinical presentations. Individuals may have localised presentations for example with abdominal or musculoskeletal disease with or without constitutional symptoms. Sometimes localised TB may precede systemic infection or be the only manifestation of active disease, for example ocular and cutaneous TB, and the spectrum of clinical manifestations are described which should prompt a clinician to investigate further. Atypical infection in those with underlying immunosuppression is also explored within this chapter.