Streptococcus agalactiae clinical isolates in Northwest Iran: antibiotic susceptibility, molecular typing, and biofilm formation.

Background: Group B Streptococcus (S. agalactiae) is one of the colonizing bacteria in pregnant women which can be a causative agent of meningitis and neonatal sepsis. This organism has also been increasingly related to invasive infections in non-pregnant adults. Objective: In present study, we aimed to characterize the clonality of biofilm-producing S. agalactiae isolates from various sources from two different clinical laboratories in Tehran, Iran. Materials and Methods: S. agalactiae isolates were collected from community-acquired (CA) and hospital-acquired (HA) infections in pregnant and non-pregnant adults. The antimicrobial susceptibility patterns and biofilm formation ability were determined. In addition, pulse field gel electrophoresis (PFGE) was used to verify the clonal diversity of isolates. Results: Out of the 87 isolates, 15 (16.6%) formed biofilm. The antibiotic resistance rate was 98.85% for clindamycin, 98.85% for tetracycline, followed by 29.88% for erythromycin, 9.19% for moxifloxacin and 6.89% for levofloxacin. The PFGE patterns revealed a total of 16 different clusters consisting of 6 single types (STs). Conclusion: This study evaluated the biofilm formation of clinical S. agalactiae, which may be a step towards understanding its role in pathological processes. Biofilm formation was significant only in the hypervirulent ST-17 clone. Intraclonal spread of isolates indicates that a local lineage of isolates is responsible for infection by these bacteria.

HIV-1 drug resistance mutations detection and HIV-1 subtype G report by using next-generation sequencing platform.

BACKGROUND: Based on world health organization (WHO) recommend, drug resistance assay should be performed in initial of treatment and after treatment for administering and monitoring of anti-retroviral regime in HIV-1 infected patients. MATERIAL AND METHOD: NGS analyses were performed on forty-one plasma samples from HIV-1 affected patients using the Sentosa SQ HIV genotyping assay (Vela-Diagnostics, Germany). This system comprises a semi-automated Ion torrent based platform and the sequencing results were analyzed based on ANRS, REGA and Stanford drug resistance algorithms. Phylogenetic analysis was analyzed based on https://comet.lih.lu database as well as MEGA5 Software. RESULTS: Drug resistances were identified in thirty-three samples (80%) out of forty-one samples. The Phylogenetic analysis results showed that CRF-35AD (94%) and subtypes B (2.4%) and G (2.4%) were dominant subtypes in this study. NRTI and NNRTI associated dominant mutations were M184I/V and K103 N.High-level resistance to lamivudine (3 TC) and Emtricitabine (FTC) were detected in 34.3% of patients while 53.1% were resistant to Efavirenz (EFV) and Nevirapine (NVP). The Protease inhibitor (PI) minor and major mutations were not reported but more than 95% of samples had polymorphisms mutation in K20R, M36I, H69K, L89 M positions. These mutations are subtype dependent and completely are absent in subtype B virus. The secondary mutations were reported in positions of E157Q, S230 N, and T97A of integrase gene and four samples represent low-level resistance to integrase strand transfer inhibitor (INSTI). CONCLUSIONS: This is the first preliminary evaluation of HIV-1 drug resistance mutation (DRM) by using the Sentosa SQ HIV Genotyping Assay in Iran. The NGS represent a promising tool for the accurate detection of DRMs of CRF-35AD that is dominant subtype in Iranian HIV-1 infected population and for the first time revealed HIV-1 subtype G in Iranian population. In the present study polymorphic mutation in the position of K20R, M36I, H69K, L89 M were properly reported in CRF35AD that is dominant in Iranian HIV patients.

Molecular technique for detection of Leishmania infantum isolates in Iran.

INTRODUCTION: Leishmania infantum is the causative agent of autochthonous cutaneous and visceral cases of leishmaniasis and transmitted by female sandflies. The dogs are considered the main reservoir hosts; however, there are the reports on Leishmania infection in other animals. In this study, occurrence types of L. infantum isolates have been analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. MATERIALS AND METHODS: In this experimental study, 77 samples were cultured and prepared for microscopic study and examined through PCR-RFLP. The samples were used for both deoxyribonucleic acid (DNA) and smear-slide preparations. The DNAs were amplified by PCR for the detection of Leishmania subgenus and PCR products were restricted with HaeIII for the species differentiation. RESULTS: The visceral Leishmania parasites were genotyped as L. infantum. It was also determined sensitivity in PCR (100%) was higher than microscopic examination. CONCLUSION: PCR-RFLP technique appears to be most sensitive for the detection and differentiation of L. infantum. There exists a relationship between genetic heterogeneousness and clinical manifestation and geographical regions of this disease in human.