Open Access18S ribosomal DNA based PCR diagnostic assay for Trichomonas vaginalis infection in symptomatic and asymptomatic women in India
Author(s) -
Surya Prakash Dwivedi,
Nuzhat Husain,
Singh Rb,
Nancy Malla
Publication year - 2012
Publication title -
asian pacific journal of tropical disease
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.208
H-Index - 33
ISSN - 2222-1808
DOI - 10.1016/s2222-1808(12)60031-0
Subject(s) - trichomonas vaginalis , trichomoniasis , biology , haeiii , polymerase chain reaction , restriction enzyme , restriction fragment length polymorphism , nested polymerase chain reaction , genotype , virology , microbiology and biotechnology , gene , medicine , genetics , gynecology
Objective: To identify the cases of trichomoniasis in symptomatic and asymptomatic\udTrichomonas vaginalis (T. vaginalis) infected patients by PCR amplification of hypervariable\ud18S rRNA gene and to assess the sensitivity of restriction fragment length polymorphism (RFLP)\udtechnique for their diagnosis. Methods: We enrolled 498 women of child bearing age groups, with\udtheir pre-informed consent, attending OPD for their routine checkups and STI related problems.\udTrichomoniasis was diagnosed on the basis of wet mount preparations and PCR with a primer set\udtargeting a well-conserved region in the 18S rRNA genes of T. vaginalis, respectively. Sequencing\udwas done for differentiating the symptomatic and asymptomatic strains of axenic and clinical\udisolates. Results: After PCR diagnosis T. vaginalis infection was detected in 17 (3.42%) out of\ud498 clinical isolates. Seventeen axenic and sixteen clinical strains of T. vaginalis tested were\udsuccessfully detected by PCR yielding a single predicted product of 312 bp in gel electrophoresis\udfollowed by restriction digestion with restriction endonuclease HaeIII. After restriction digestion\udthey gave two bands, one of 101 and the other of 211 bp, while there was negative response with\udDNA from Chlamydia trachomatis, Neisseria gonorrhoeae, Giardia lamblia, Toxoplasma gondii,\udLeishmania donovani and Entamoeba histolytica. An optimal analytical sensitivity and specificity\udof one T. vaginalis organism per PCR was achieved. Sequence of symptomatic and asymptomatic\udstrains of axenic and clinical isolates are somewhat differentiated on the basis of point mutations\udin their 18S rRNA gene. Conclusions: Only few factors are known to predict symptoms of T.\udvaginalis infection, although the majority of women are infected with trichomoniasis are reported.\udTherefore the application of sensitive PCR based diagnosis may be quite useful for routine\uddiagnosis of T. vaginalis strains