Feodorova Valentina, Sultanakhmedov Edgar, Saltykov Yury, Zaitsev Sergey, Utz Sergey, Corbel Michael, Gaydos Charlotte, Quinn Thomas, Motin Vladimir
Laboratory for Molecular Biology and NanoBiotechnology, Federal Research Center for Virology and Microbiology, Branch in Saratov, Ap. 6, the 53 Strelkovoi Divisii Street, Saratov, 410028, Russia.
Department for Skin Diseases, Saratov State Medical University, 22, Proviantskaya Street, Saratov, 410028, Russia.
Open Microbiol J. 2018 Oct 18;12:343-352. doi: 10.2174/1874285801812010343. eCollection 2018.
Chronic asymptomatic chlamydial genital infection caused by the wild-type of (wtCT) is the most common bacterial infection causing human infertility. The novel 'Swedish' variant of (nvCT) which contains a 377 bp deletion in a region that is specifically targeted in some nucleic acid amplification tests may impede diagnosis.
The study aimed to investigate whether nvCT may be a possible cause of infertility in a couple undergoing fertilization (IVF).
Clinical specimens from both genital (urethra and cervix) and extra-genital sites (pharynx, conjunctive, blood) of a couple who experienced multiple unsuccessful attempts at pregnancy by natural fertilization and IVF procedures were analyzed before and after antibiotic therapy. Both partners had neither somatic nor endocrinal abnormality nor any clinically apparent genital manifestations of or other STIs.
Before antibiotic therapy all the samples of the Female Partner (FP) contained DNA of only the nvCT. After antibiotic therapy, additionally, DNA of wtCT of genovars E and D was detected in specimens from her conjunctiva and oropharynx. All samples of the Male Partner (MP) revealed co-infection of nvCT and wtCT. Identical SNP within the variable region 4 (VD4) of the gene confirmed the identity of the wtCT strains found in both partners. The FP had a positive anti-chlamydial IgG titer. The sperm characteristics of the MP, motility (immotile spermatozoa was 51.1% versus 21.6%) and vitality (46% versus 68%) declined progressively, and the MP anti-chlamydial IgG titer was negative.
Infertility in this couple may have been caused by chronic asymptomatic and persistent nvCT-associated infection that was complicated by re-infection later with wtCT. This study illustrates the importance of including detection methods for nvCT strains in the investigation of infertility cases.
由野生型沙眼衣原体（wtCT）引起的慢性无症状衣原体性生殖器感染是导致人类不孕的最常见细菌感染。新型“瑞典”变种沙眼衣原体（nvCT）在某些核酸扩增检测的特定靶向区域存在377 bp的缺失，这可能会妨碍诊断。
本研究旨在调查nvCT是否可能是一对接受体外受精（IVF）的夫妇不孕的原因。
对一对通过自然受精和IVF程序多次尝试怀孕均未成功的夫妇的生殖器（尿道和宫颈）及生殖器外部位（咽部、结膜、血液）的临床标本在抗生素治疗前后进行分析。夫妇双方均无躯体或内分泌异常，也无任何明显的衣原体或其他性传播感染的生殖器临床表现。
抗生素治疗前，女性伴侣（FP）的所有样本仅含有nvCT的DNA。抗生素治疗后，在她的结膜和口咽标本中还检测到了基因型E和D的wtCT的DNA。男性伴侣（MP）的所有样本均显示nvCT和wtCT的合并感染。在沙眼衣原体基因可变区4（VD4）内相同的单核苷酸多态性（SNP）证实了在夫妇双方中发现的wtCT菌株的一致性。FP的抗衣原体IgG滴度呈阳性。MP的精子特征，即活力（不动精子比例从51.1%降至21.6%）和活力（从46%降至68%）逐渐下降，且MP的抗衣原体IgG滴度为阴性。
这对夫妇的不孕可能是由慢性无症状且持续的nvCT相关感染引起的，随后又并发了wtCT的再次感染。本研究说明了在不孕症病例调查中纳入nvCT菌株检测方法的重要性。
