DIAGNOSIS OF UROGENITAL CHLAMYDIA-TRACHOMATIS INFECTION IN WOMEN BASED ON MAILED SAMPLES OBTAINED AT HOME - MULTIPRACTICE COMPARATIVE-STUDY

Objective-To compare urine and vaginal flush samples collected by wome n at home with endocervical and urethral swabs obtained by general pra ctitioners for their efficacy in the diagnosis of urogenital Chlamydia trachomatis infection. Design-Multipractice comparative study. Settin g-33 general practices and a central department of clinical microbiolo gy in Aarhus County, Denmark. Subjects-222 women aged 18-25 years who for any reason had a gynaecological examination. Interventions-Endocer vical and urethral swabs were obtained by the women's general practiti oners. The same women when at home then collected a first void urine s ample, a midstream urine sample, and a vaginal flush sample (using a v aginal pipette) and mailed them to the laboratory. Main outcome measur es-C trachomatis detected by the polymerase chain reaction and the lig ase chain reaction. Eight tests for C trachomatis were performed for e very woman. When two of the eight yielded positive results the patient was considered infected. Results-The overall prevalence of C trachoma tis infection was 11.2% (23/205 women). Test sensitivities in samples obtained by general practitioners, samples obtained at home subjected to polymerase chain reaction, and samples obtained at home subjected t o ligase chain reaction were 91%, 96%, and 100% respectively. The corr esponding specificities were 100%, 92.9%, and 99.5%. Conclusions-The d iagnostic efficacy of samples obtained by women at home acid mailed to the laboratory was as good as for samples obtained by a general pract itioner when using the ligase chain reaction. This may have important implications for the practicability of screening for this common, ofte n asymptomatic, and treatable infection.