Standardization of gastric aspirate technique improves yield in the diagnosis of tuberculosis in children.

Abstract

The diagnosis of tuberculous disease in children remains a difficult one, based on epidemiologic investigation, Mantoux skin testing and suggestive radiologic findings. Because children with pulmonary tuberculosis are unable to produce sputum, gastric aspirates remain the procedure of choice for microbiologic confirmation of tuberculous disease; however, yield is frequently low. To evaluate the effect of a standardized gastric aspirate collection protocol on diagnostic culture yield. The gastric aspirate culture yield for Mycobacterium tuberculosis in 13 historical control children with clinically confirmed tuberculosis from 1979 to 1994 was compared with the yield in 8 children with tuberculous disease after institution of a standardized gastric aspirate collection protocol involving physician education, strict timing of collection, base neutralization of aspirate specimens and expedited processing. Retrospective survey of gastric aspirate results in Rhode Island from 1979 to 1994 revealed that only 1 of 13 cases (8%) of pediatric pulmonary tuberculosis were confirmed in this manner. During a 12-month period after institution of a protocol, gastric aspirates yielded positive cultures in 4 of 8 children (50%) with pulmonary tuberculosis, a yield that compares favorably with the sensitivities of 20 to 52% published in the literature. Attention to the technique of gastric aspirate collection, and expedited processing in particular, appears to improve the yield of this diagnostic procedure for pediatric tuberculosis.