We are carrying on the basic and clinical investigations of transbronchial bacteriological culture studies using the flexible fiberoptic bronchoscope.<BR>This time we would like to present some of the results of bacteriological culture studies with some of the asscciated problems through the transtracheal tube method. Sixty point five % of positive bacterial cultures were obtained from a total of 172 cases, consisting of 16 kinds of chest diseases.<BR>In each disease in which we examined more than 10 cases, the higher positive bacterial culterial groups were, lung abscess 100%, chronic bronchitis 82%, tumor of the lung 80% and bronchiectasis 75%; on the other hand, lower positive bacterial culture groups were pulmonary tuberculosis, 16.7% and the cases examined for the purpose of excluding cancer, 33.3%.<BR>Approximately 10 kinds of causative microbials were identified in the both groups. Secretions came from different diseases and different tracheobronchial areas showed their own microorganisms and different positive culture rates.<BR>No microorganisms were cultured from clear serous and white tenaceous secretions, except those located on hyperemic mucosa and with stenotic or ectatic lumens; however, several kinds of microorganisms were cultured from yellowish, brownish and greenish secretions.<BR>In reference to contamination within the lumen of the tracheal tube immediately after intubation, positive bacterial cultures were obtained from the swab-sponges at 12.5%, so the contamination rate of the channel of the fiberoptic bronchoscope caused by passing through the tracheal tube, will be under 12.5%, however comparative bacteriological identification between the secretions from the tracheal tube (sputum) and from the fiberscope channel should be done for diagnostic and therapeutic purpose.<BR>“PRELEVEMENTS BRONCHIQUES AU MOYEN DU FIBROSCOPE: ETUDE BACTERIOLOGIQUE ET PROBLEMES DE CONTAMINATION DES CANULES ENDO-TRACHEALES APRES INTUBATION”<BR>Nous voudrions presenter, dans le cadre d'une étude clinique et bactériologique, les résultats obtenus à partir de prélèvements endoscopiques par bronchofibroscope en essayant d'apprecier l'influence éventuelle du passage du fibroscope dans une canule d'intubation.<BR>Sur un total de 172 prelevements concernant 16 affections broncho-pulmonaires différentes, les cultures furent positives dans 60.5% des cas-Eu ce qui concerne les maladies pour lesquelles plus de 10 cas furent réunis les pourcentages les puls éléves concernaient les abcès du poumon (100%), les bronchites chroniques (82%), les tumeures broncho-pulmonaires (80%) et les bronchectasies (75%); les plus bas: les cas examinés pour la exclusion de cancer (33.3%) et la tuberculose pulmonaire (16.7%).<BR>Environ 10 espèces microbiennes furent identifiées. Suivant la maladie et le territoire concerné par le prélèvement, les souches différaient par le germe en cause et pourcentage de détection.