A clinical view of tuberculosis.

Although tuberculosis (TB) involves the lungs most commonly, nonpulmonary sites of disease are increasingly common. The modes of presentation of TB and the approach to diagnosis depend on the extent of the disease and the organs that are affected. In addition, TB involving any site commonly causes systemic symptoms such as fever and weight loss. Early and accurate diagnoses depend on recognition of the systemic and local manifestations of TB, the obtaining of appropriate diagnostic tests, and the correct interpretation of results.