Fortuitous diagnosis of Trichomoniasis by PCR using panfungal primers

Abstract

We report the unusual diagnosis of trichomoniasis in an 18 year old patient suffering from salpingitis. Chlamydiae, Mycoplasma and Gardnerella vaginalis were diagnosed using classic laboratory procedures. However, T. vaginalis infection was assessed fortuitously by Polymerase Chain Reaction (PCR) followed by sequencing using panfungal primers (NL1/NL4) on a vaginal swab. This cross-reactivity of panfungal primers was further confirmed using a specific T. vaginalis PCR as well as a reference strain of T. vaginalis isolated in culture. Such cross-reactivity of panfungal primers has been previously reported with non-fungal eukaryotes (Taenia solium, Strongyloides stercoralis or Toxoplasma gondii DNA). This case highlights the usefulness of broad range molecular tools that can take advantage of this cross-reactivity in order to diagnose unsuspected pathogens. In particular settings (e.g. immunosuppression, infection without etiology) it should be used to detect pathogens across kingdoms. Thus, such tools would help direct care providers toward appropriate treatment regimens and better management of unsuspected infection etiologies. Keywords: Trichomonas vaginalis, PCR, Broad range, Panfungal