Treponema pallidum diagnosed in Thi-Qar province, Iraq

This study aimed to determine the levels of some immunoglobulins (IgG, IgA and IgM), Complement 3 concentration and diagnosis of Treponema pallidum PolA gene using PCR technology. The study was conducted in Dhi Qar between September and November 2023 and a total of 489 people participated in the study. The ages of the participants ranged from 18 to 57 years. For this study, an additional serum sample was collected from participants to identify a specific treponemal antibody. Five to ten millilitres of serum sample was collected from each study participant by venipuncture using disposable syringes. 4 mL of the sample was placed in disposable plastic tubes and kept at room temperature for five minutes to coagulate. The sera were then extracted by centrifugation for five minutes. Aliquots with a volume of 250 µL were then stored at -20°C until testing. To avoid freezing and thawing, the serum was applied only once to each aliquot. The results obtained showed that out of a total of 489 individuals, 9 (1.84%) were positive and 480 (98.16%) were negative for the test to detect the presence of T. pallidum in the participants. The present results showed that there was a relationship between T. pallidum infection and age; the rate in the 15-25 age group was 33.3% and in the 26-40 age group was 33.3%. The rate in the 41-55 age group was 22.2%. The rate in the 55+ age group was 11.1%. IgA (245.02±14.74), IgG (1385.51±62.91) and IgM (392.61±37.42) levels in the infected group showed a highly significant (P<0.05) increase compared to the control group (183.95±9.44; 1135.46±57.09 and 138.74±24.58). C3 levels in the infected group (208.57±15.92) showed a highly significant (P<0.05) increase compared to the control group (127.45±8.63). The results of the PCR test to detect the polA gene showed that all 9 positive isolates (n=9) identified as T. pallidum contained the polA gene.