Tuberculosis in the elderly.

Although the cause of the steady increase in tuberculosis (TB) notifications in England and Wales since 1987 is multifactorial, the elderly have made an appreciable contribution. From 1987-1989 the increase was 6% for all ages combined, but 13% in females and 16% in males over the age of 75. Tuberculosis in the elderly therefore remains an appreciable problem. Although the characteristic presentation of chronic cough, malaise and weight loss, with cavitatory changes in the upper lobes still predominates in the elderly, there has been an increased incidence of cryptic miliary disease in which the onset is insidious and chest X-ray often normal. The diagnosis must often be made on suspicion and treatment started before a positive diagnosis is obtained. The elderly are more likely to suffer adverse effects from the anti-tuberculous chemotherapy than the younger population and greater care must be taken. Drug resistance is uncommon in the elderly in the UK. Isoniazid, rifampicin and pyrazinamide are appropriate for the initial two months of treatment. Rifampicin and isoniazid should be continued for a further four months for disease at virtually any site, with the exception of TB meningitis, when a further 10 months therapy should be given. In the UK, preventative therapy in the form of isoniazid or rifampicin and isoniazid probably has no place in disease control in an elderly population; tuberculin tests are frequently negative, even in the presence of active disease, as elderly patients are often anergic.