Mycobacterial lymphadenitis in childhood.

A total of 42 cases of childhood mycobacterial adenitis have been studied to define the optimal steps that lead to the correct diagnosis of this disease. Antigens from the atypical mycobacteria are not currently available, so the usefulness of tuberculin skin testing as a diagnostic tool was examined. Skin testing differentiates mycobacterial adenitis from infection caused by pyogenic bacteria. In addition, repetitive skin testing with tuberculin over a three- to six-month period is also useful in differentiating adenitis caused by atypical mycobacteria from that due to Mycobacterium tuberculosis. Children with atypical mycobacterial adenitis have a decreasing tuberculin response to repeated testing, while children with tuberculous adenitis have a stable response. Other factors that assist in the differentiation of adenitides include a history of recent exposure to tuberculosis and evidence of extralymphatic tuberculosis. Needle aspiration or partial excision in mycobacterial adenitis may lead to drainage and sinus tract information. A PPD skin test should be done prior to surgical manipulation of enlarged nodes. Children with reactive skin tests should undergo complete excision.