Comparison of scrape, swab, and cytobrush samples for the diagnosis of cervical chlamydial infection by immunofluorescence.

An endocervical swab, cytologic scraper, and endocervical cytobrush were used to prepare simultaneous full-slide smears for immunofluorescence for the diagnosis of cervical chlamydial infection. The cytobrush produced the best sample, with significantly higher numbers of organisms. Most of the false negative results were obtained with the cytologic scraper. The optimum technique appears to be to use a cytobrush sample; however, a swab should be used with pregnant patients.