Cytopathologic detection of chlamydia trachomatis in vaginopancervical (fast) smears

Abstract

The value of the Papanicolaou-stained vaginopancervical (Fast) smear in the detection of chlamydial infection has been disputed. We examined 116 satisfactory Fast smears from 203 women enrolled in the Johns Hopkins Fertility Control Clinic and compared tissue-culture results with cytopathologic detection using various published morphologic criteria. All Chlamydia culture-positive cases were reviewed, and certain cytologic features considered helpful in the detection of chlamydial infection in cervical smears obtained from this selected high-risk population were identified. The changes that had the highest correlation with tissue culture included fine vacuolation of metaplastic endocervical cells, giving their cytoplasm a rarefied "moth-eaten" appearance. Using these criteria, cytopathologic changes of chlamydial infection were observed in 24 of 28 cases of tissue-culture-positive cases and in 8 of 88 tissue-culture-negative cases. The sensitivity and specificity of the Fast-smear cytodiagnosis of Chlamydia infection utilizing these morphologic changes and compared with tissue culture were 86% and 91%, respectively. Other cytologic features, including inflammatory background and intracytoplasmic structures consistent with initial and intermediate chlamydial bodies within the metaplastic cells, were found to be useful although less specific and less sensitive. The implications of these diagnostic features, the conditions to be considered in their differential diagnosis, and the pitfalls of chlamydial cytodiagnosis and the chlamydia culture studies have been critically reviewed. Study design and the high unsatisfactory cervical smear rate are discussed.

Effect of endocervical specimen quality on detection of Chlamydia trachomatis and on the incidence of false-positive results with the Chlamydiazyme method

“…No attempt was made during this evaluation to detect intracellular inclusion bodies of C. trachomatis in Pap-stained smears from infected patients, because such a microscopic analysis has been previously shown to be insensitive (1, 10-12, 23, 25, 31). Failure to observe intracellular inclusions may be due either to the poor quality of many specimens or to too few well-preserved cells in the sample (1,(10)(11)(12). Epithelial cells containing intact inclusions are very fragile and are rarely well preserved (25).…”

“…An adequate female genital specimen for detection of C. trachomatis by culture or antigen assay is one containing metaplastic cells or columnar or cuboidal epithelial cells from the endocervix, the cell types infected by the pathogen (2,6,11,12,23,33,35). In the current study, these cells were detected more frequently in specimens which contained RBCs and PMNs.…”

Trends in Inflammatory Status of the Vaginal Flora as Established in the Dutch National Screening Program for Cervical Cancer Over the Last Decade

“…Different types of "diagnostic" inclusion bodies have been observed. 23,24 Studies on cytologic diagnosis of Chlamydia infection based on the detection of various inclusion bodies display an average sensitivity of 27% and an average specificity of 79%, with large numbers of false positive and false negative results. 14,22 Nowadays, the conclusive diagnosis of C trachomatis requires confirmation by PCR.…”

Pap smear follow-up of possible role of mucopurulent exudate as a prognosticator of a negative pregnancy outcome

“…Additionally, the Gram stain adds cost to the prenatal care of pregnant women. 22 The advantage of the Pap smear over the Gram stain is several-fold: 1) the Pap smear is about equal to or better than the Gram stain in detecting bacterial flora, including lactobacilli, lepothrix, and coccobacilli associated with bacterial vaginosis; 21 2) the Pap smear permits the identification of other pathogens, not identifiable by the Gram stain, such as HSV, 23 chlamydia, 24 and human papilloma virus (HPV); 25 and 3) the Pap smear detects premalignant epithelial and malignant abnormalities. 26 In addition, the Pap smear may be studied by immunocytochemical methods in the specific documentation of chlamydia, 27 HSV subtypes, 28 and HPV.…”