Genotyping of toxoplasma gondi strains in patients affected by ocular toxoplasmosis

Purpose: to identify the type ocular toxoplasmosis responsible for retinochoroiditis in patients coming to khatam alanbiya hospital in mashhad in 2017-2018 Methods: 24 patients who have been clinically diagnosed with active toxoplasmic retinochoroiditis at the uveitis clinic in khatam al anbiya hospital , at the same time where given the corresponding treatment and toxoplasma serology tests and PCR for the RE , B1 and GRA6 genes were performed. RE and B1 genes to confirm the presence of toxoplasma gondi and GRA6 gene to indicate it’s type. bands were separated using electrophoresis in order to identify their sequence. Results: Out of 24 patients , 2 patients were excluded from the study because of negative serology results for toxoplasma . 12 (54.5%) patients were females 10 (45.5%) were males. The common complaint in patients was blurred vision (95.5%) and floater (54%) . out of 18 (81.84%) patients who had toxoretinitis in zone 1 , 10 patients (45.5%) due to sight threatening lesion were treated by intravitreal clindamycin + dexamethasone along with oral antibiotics and the rest of patients were only given oral azithromycin and co-trimoxazole. One patient had undergone pp.vitrectomy because of uveitis complications.22 samples were RE positive , 20 samples were B1 positive. Out of 15 samples that were GRA6 positive 10 were sent for sequencing and toxoplasma type 3 was specified. Conclusion: Type 3 toxoplasma has the highest prevalence in khorasan and is responsible of retinochoroiditis