Value of anti-contamination specimen brush in the etiologic diagnosis of bacterial pulmonary infections

This paper reports the results of sampling the secretion of lower respiratory tract by protected specimen brush(PSB) via fiberoptic bronchoscope for the isolation of pathogenic organisms in laboratory and clinic. Studies in vitro showed that the technique of PSB is better than that of single shear catheter brush (SSC) or cytologic brush (CB) for anti-contamination. The specificity and sensitivity of sampling were 93% and 100% respectively. The application of PSB in the diagnosis of pneumonia in canine models revealed that both specificity and sensitivity were 100% Sampling in 18 cases of pulmonary bacterial infections and 17 cases of other pulmonary diffusing diseases indicated that the specificity and sensitivity were 86% and 94% respectively. The authors are of the opinion that PSB sampling technique has a better anti-contamination effect and can increase the isolation rate of pathogens. The PSB may be a satisfactory sampling tool in etiologic diagnosis of pulmonary infections.