RELIABILITY OF GASTRIC SMEARS BY AURAMINE-RHODAMINE STAINING TECHNIQUE FOR DIAGNOSIS OF TUBERCULOSIS

Abstract

From 1972-1974, all sputum specimens and gastric aspirate specimens submitted to the University of Michigan Laboratory [USA], for acid-fast smear and culture were studied. Specimens were paired for culture and smear results using auramine-rhodamine staining. Of 1893 patients, 75 patients without prior antituberculous therapy, had a positive smear or a positive culture of sputum or gastric material. The data analyzed by patient source revealed that staining sputum with auramine-rhodamine is a clinically reliable technique for detecting pulmonary tuberculosis; it demonstrates a sensitivity of 78% and a relative fraction of false-positive smears of only 11%. Staining gastric-aspirated material by the auramine-rhodamine technique is apparently not a clinically reliable method as a routine procedure for the detection of pulmonary tuberculosis, because of a sensitivity of only 58.8% and a relative fraction of false-positive smears of 33%. In the absence of sputum in suspected clinical granulomatous disease, quantified gastric smears may be helpful. When > 6 organisms/high power field were found, the patient''s sputum or gastric material yielded a pathogenic Mycobacterium on culture.