Candida precipitins in pregnant women: validity of the test systems used

Abstract

Sera from 200 pregnant women, with symptoms suggestive of vaginitis and harbouring yeast in the vagina, were examined for precipitating antibodies to 3 antigens of C. albicans, using a gel double diffusion test. A high overall incidence of precipitin positive sera (47.5%) was found compared with an incidence of 18% in the unselected pregnant population previously studied. Using the clinicopathological criteria of Caroll, Hurley, and Stanley (1973), a final aetiological diagnosis of C. albicans mycosis was reached in 75 cases and precipitins were demonstrated in 64%. Forty eight women harbouring C. albicans responded favourably to a single course of antifungal treatment, and probably had mycotic vaginitis. The incidence of precipitins in this group was 42%. C. albicans was isolated from a further 55 of 62 patients, in whom the incidence of precipitins was 32%. 'Booking' sera were investigated from 50 of the 200 women studied. Sixty four per cent of women had symptoms of vaginitis at booking and 32% were precipitin positive. Twenty eight per cent had precipitins on both occasions, and a further 24% acquired candida precipitins during pregnancy. None of the 7 newborn with oral or skin thrush had precipitins to C. albicans. The results indicate that the detection of precipitating antibodies to C. albicans, particularly to all 3 of the antigens described, would be a useful additional criterion in the diagnosis of Candida vaginitis, particularly if the vaginitis were persistent, recurrent, or unresponsive to therapy. The sensitivity of the test system used was 64%, and its specificity 87%; as such, the test is valid and may be reasonably useful as a screening procedure.