Objectives: The aim of this study was to develop a novel urine transport method to be used in self collection-based screening for Chlamydia trachomatis (C. trachomatis). The method needed to be suitable for C. trachomatis PCR detection, be economical, and suitable for transport by standard envelope mailing.
Methods: An anhydrous gel composed of superabsorbent polymer and buffering agent was used to desiccate urine into a dry granulous state, which could subsequently be reconstituted upon arrival at a laboratory. DNA was then extracted from the reconstituted solution using the Roche MagNA Pure protocol for the detection of C. trachomatis by PCR. Collections of urine specimens from three populations with widely differing chlamydia prevalences (100% (n=56); 47% (n=70) and 3% (n=97)) were used. We determined the gel method's impact on C. trachomatis PCR sensitivity and specificity using neat and gel-processed urine specimens. An equine herpes virus PCR was used to test for assay inhibition.
Results: Overall, the sensitivity of the gel based method ranged from 94.6 to 100% compared to neat urine, with a specificity of 100%. No PCR inhibition or decrease in analytical sensitivity was observed using the gel-processed extracts.
Conclusions: The gel-based method was found to be suitable for the detection of C. trachomatis by PCR. In addition, its ease of use, effectiveness at ambient temperature, and low cost makes it well suited for self-collection kits used in population-based C. trachomatis screening, particularly for geographically and socially isolated individuals.