Valerie C. Stanley

Microbial flora of the lower genital tract during pregnancy: relationship to morbidity.

Nineteen genera and groups of micro-organisms were isolated from the lower genital tract of 280 women at their first antenatal visit. Chlamydia, viruses, and T-strain mycoplasmas were not sought, and only routine methods of anaerobic culture were used. Growth was recorded as scanty, moderate or heavy. The population studied was grouped according to age, parity, gestational stage at booking, presence and degree of severity of lower genital tract morbidity, past history of vulvovaginitis, and suspicion of lower genital tract morbidity as evidenced by a request for a report on the microbiological findings. The frequency of isolation of the various microbes in health and in disease is given. The grading of Gram-stained smears bore no relation to the isolation rates of lactobacilli, but there was a significant increase (p less than 0-001) in the isolation rates of each of the following: Mycoplasma hominis, Bacteroides spp., Trichomonas vaginalis, Gram-variable cocco-bacilli, and anaerobic streptococci in those patients with smears in which lactobacilli were adjudged to be absent. The isolation of faecal streptococci was increased (p less than 0-001) in women aged more than 34 years. Escherichia coli (p less than 0-05) and anaerobic and microaerophilic streptococci (p less than 0-02) were isolated more frequently from those booking after the 25th week of pregnancy. The incidence of M. hominis (p less than 0-02) and of anaerobic streptococci (p less than 0-05) increased between the first and third trimesters. No significance positive correlations were established between the isolation rates of the various microbes and objective assessment of lower genital tract morbidity or the demonstration of pus cells, but lactobacilli were isolated less frequently (p less than 0-01) from those with morbidity. The isolation of Candida albicans (p less than 0-02), T. vaginalis (p less than 0-05), and M. hominis (p less than 0.05) was increased in patients in whom vulvovaginitis was suspected, and that of T. vaginalis (p less than 0-05) was increased in those with a past history of vulvovaginitis. The study indicates that, other than the pathogens T. vaginalis and C. albicans, only M. Hominis could be suspected, on statistical grounds, of being associated with disease of the lower genital tract during early pregnancy.

CRITERIA FOR DIAGNOSIS OF CANDIDA VULVOVAGINITIS IN PREGNANT WOMEN

In this prospective study of 303 pregnant women C. albkans was found in 50 patients (16‐5 per cent) but only once was it isolated from the healthy vagina. The majority of isolates (84 per cent) were associated with signs of vaginitis or vulvovaginitis. In the remainder, isolation of the fungus was associated with discharge or other sign of morbidity. Discharge and irritation were not specifically associated with isolation of the thrush fungus, but 85 per cent of women with vaginitis during pregnancy had precipitins in their serum, or C. albicans in the vagina. Candida albicans was isolated from 23 of 28 women with vulvitis, and from 11 out of 16 women with vaginal plaques or a cheesy appearance of the vaginal epithelium.

Cytopathic effects of pathogenic and non-pathogenic species of Candida on cultured mouse epithelial cells: relation to the growth rate and morphology of the fungi.

Summary The cytopathic effects of standard inocula (30,000 blastospores per ml) of Candida albicans, C. tropicalis, C. stellatoidea, C. krusei, C. pseudotropicalis, C. parapsilosis and C. guilliermondii (isolated from man) on murine renal epithelial cells in culture were compared with those of C. cacaoi, C. diddensii, C. kefyri, C. blankii, C. ingens and C. shehatae (isolated from non-human sources). The nature of the changes in the mammalian cells, and the extent of their destruction, were shown to be correlated with the growth rate and with the proportion of mycelium in the growing fungi. The presence of mammalian cells induced filamentous change in some species. These experiments demonstrate the greater importance of the M phase in the progression of Candida lesions, because of the more widespread involvement of cells by organisms with rapid growth rates, but they do not demonstrate a qualitative difference in the cytopathic effects of the M and Y phases. They suggest that in vivo the Y phase may initiate infection, as it does experimentally, and that the M phase is associated with the more rapidly growing species and with extension of the lesion. The filamentous phase may be induced by exposure of the fungi to cellular exudates or transudates.

Distribution and significance of Candida precipitins in sera from pregnant women.

Summary Sera from 303 pregnant women were examined for antibodies to Candida by means of a precipitin test in gel. Three preparations derived from C. albicans, type A (mannan antigen, cytoplasmic antigen and culture-filtrate antigen), were used, each at two concentrations. Precipitins to all three antigens were found more frequently in the sera of women with mycotic vulvovaginitis than of other women. When serum precipitins were present and C. albicans was isolated from the vagina there was nearly always clinical evidence of vaginal thrush.

Microbial ecology of the female lower genital tract during pregnancy

The posterior fornices of the vagina of 280 unselected pregnant women were sampled, using a sponge swab, squeezed out into Stuarts Transport Medium. Other specimens were also taken. Eleven primary media were inoculated, wet swabs were examined, and Gramstained smears were also made. Nineteen groups or species of microbes were identified. Nearly 80% of women harbour pathogenic, or potentially pathogenic microbes; 52% harbour streptococci of various sorts. The incidence of the various groups, and species of microbes is tabulated. There is a statistically significant correlation between the presence of polymorphonuclear leucocytes in excess of one per high power field, and the presence of lesions of the cervix.

Morbidity of the lower genital tract during pregnancy.

The lower genital tract of 280 pregnant women was studied in detail, and symptoms relevant to its morbidity were elicited and recorded. The study was contemporaneous with a study of microbial flora in the genital tract of these women (de Louvois et al, 1975). Complaint was made frequently of discharge (42%), irritation (15%), or both (11%). Apart from these symptoms, 14% admitted a past history of vulvovaginitis, emphasizing the importance of this condition in obstetric and gynaecological practice. The notorious discrepancy between the complaint, and the objective demonstration of discharge, was confirmed, but a significant difference in observations, varying with the clinical observer (P less than 0-001), was also demonstrated. This illustrates the necessity of even more accurate grading of signs when clinicopathological correlations are to be attempted. Only 30% of women had no evidence of vulvovaginitis or cervicitis. Morbidity did not relate to age, gestation or parity, but there was a significant correlation between clinical acumen, as evidenced by a request for a microbiological report with a view to treatment, and morbidity (P less than 0-001), between past vulvovaginitis and present morbidity (P less than 0-01), and between cervicitis and the presence of pus cells in the smear (P less than 0-001). The results indicate that microbiological investigations should be requested when there is past history of vulvovaginitis, and that lesions of the cervix, if not already noted, should be suspected if pus cells are demonstrable in stained smears.