The Role of the Coagulase-negative Staphylococci (CoNS) in Infective Endocarditis; A Narrative Review from 2000 to 2020.

Coagulase-negative staphylococci (CoNS) are part of the microbiota of human skin and rarely linked with soft tissue infections. In recent years, CoNS species considered as one of the major nosocomial pathogens and can cause several infections such as catheter-acquired sepsis, skin infection, urinary tract infection, endophthalmitis, central nervous system shunt infection, surgical site infections, and foreign body infection. These microorganisms have a significant impact on human life and health and, as typical opportunists, cause peritonitis in individuals undergoing peritoneal dialysis. Moreover, it is revealed that these potential pathogens are mainly related to the use of indwelling or implanted in a foreign body and cause infective endocarditis (both native valve endocarditis and prosthetic valve endocarditis) in patients. In general, approximately eight percent of all cases of native valve endocarditis is associated with CoNS species, and these organisms cause death in 25% of all native valve endocarditis cases. Moreover, it is revealed that methicillin-resistant CoNS species cause 60 % of all prosthetic valve endocarditis cases. In this review, we describe the role of the CoNS species in infective endocarditis, and we explicated the reported cases of CoNS infective endocarditis in the literature from 2000 to 2020 to determine the role of CoNS in the process of infective endocarditis.

Association of CYP2C19 and HSP70 Genes Polymorphism with Aspirin- Exacerbated Respiratory Disease in a Kurd Population.

BACKGROUND: CYP2C19 a metabolizing enzyme and Heat Shock Proteins (HSP) are induced in stress conditions, such as hypoxia and ischemia. Recently, polymorphism in the CYP2C19 and HSP genes has been established in Aspirin-Exacerbated Respiratory Disease (AERD). OBJECTIVE: We investigated the polymorphism of these two genes in Kurdish patients with AERD. METHODS: This study involved 306 subjects, referred to the Be'sat hospital in Kurdistan Province, which were divided into three groups, (i) Aspirin Induced Asthma (AIA), (ii) Aspirin Tolerant Asthma (ATA), and (iii) healthy subjects as control. The subjects as control and ATA\AIA groups were verified by the physician. The demographic data of each subject with respect to age, sex, parental education, and residence was collected. Spirometry was performed on subjects and blood samples were collected for serum Immunoglobulin E (IgE) estimation and molecular tests. Genotyping was done for CYP2C19 681G>A، CYP2C19 636G>A, and HSPA1B1267A>G by using PCR- Restriction Fragment Length Polymorphism (RFLP) and for HSPA1B-179C>T by High Resolution Melting (HRM). RESULTS: Demographic statistics were not significantly different between the three groups (p>0.05). Further, genotypes were also not observed to be significantly different in the genes of CYP2C19 681G>A, CYP2C19 636G>A and HSPA1B1267A>G (p>0.05). However, the heterozygote genotype in HSPA1B-179 C>T in AIA group was higher than the control group (p<0.05). Notably, 92.8 % of the subjects showed heterozygote genotype in HSPA1B1267 A>G. In clinical tests, FEV-1, FVC, and asthma severity in the AIA group were higher than control and additionally IgE levels were lower in this group (p<0.05). CONCLUSION: The results confirm the association of polymorphism in the HSPA1B-179C>T and HSPA1B1267A>G with AERD in the Kurdish population.

Role of MexAB-OprM and MexXY-OprM efflux pumps and class 1 integrons in resistance to antibiotics in burn and Intensive Care Unit isolates of Pseudomonas aeruginosa.

BACKGROUND: The overexpression of efflux pumps and existence of class 1 integrons are the most important mechanisms that contribute to antimicrobial resistance in Pseudomonas aeruginosa especially in burn and Intensive Care Units (ICUs). The present study evaluated the role of MexAB-OprM and MexXY-OprM efflux pumps and class 1 integrons in resistance to antibiotics in burn and ICU isolates of P. aeruginosa. METHODS: Fifteen burn and forty-two ICU isolates were obtained from four hospitals in Northwest Iran. The isolates were identified and evaluated by the disk diffusion and agar dilution methods for determining antibiotic resistances. The presence of class 1 integrons and associated resistance gene cassettes were detected by PCR and sequencing of the products. The expression levels of efflux pumps were evaluated by phenotypic and genotypic (Quantitative Real-time PCR) methods. The isolates were genotyped by Random Amplified Polymorphic DNA Typing (RAPD-PCR). RESULTS: All burn isolates were integron positive and Multi-drug resistant (MDR), while 78.5% and 69% of ICU isolates were found as MDR and integron positive, respectively. The aadB gene was the most prevalent gene cassette (63.6%) followed by aacA4 (47.7%). Thirty-nine (68.4%) and 43 (75.4%) isolates exhibited an overexpression of MexAB-OprM and MexXY-OprM. Among burn isolates, 80% and 86.6% of them were mexB and mexY overexpressed, while 64.2% and 71.4% of ICU isolates exhibited mexB and mexY overexpression, correspondingly. The isolates were genotyped as 24 different RAPD profiles and were grouped into 15 clusters. CONCLUSIONS: The data suggested that class 1 integron had a more significant role than efflux pumps in resistance to beta-lactams and aminoglycosides in burn and ICUs except for gentamicin in burn isolates. Based on our data, it is possible that efflux pumps were not the main cause of high-level resistance to antibiotics.

Assessment of interferon-γ levels and leishmanin skin test results in persons recovered for leishmaniasis.

Patients who recover from leishmaniasis usually show development of strong immunity and induction of interferon-γ (IFN-γ) and delayed type hypersensitivity. In a randomized trial, we analyzed the IFN-γ response by using a Quantiferon-Leishmania assay against three Leishmania peptide antigens and compared it with results of the leishmanin skin test (LST) in persons residing in areas in Iran to which zoonotic cutaneous leishmaniasis (ZCL, 181 persons), anthroponotic cutaneous leishmaniasis (ACL, 104 persons), and zoonotic visceral leishmaniasis (ZVL, 67 persons) are endemic. The percentage of persons with an IFN-γ-positive response (> 0.2 IU/mL) to three antigens and the mean concentration of IFN-γ induced by the antigens were higher for persons from areas endemic for ZVL than for persons from areas endemic for ZCL and ACL. The percentage of persons with LST-positive results (≥ 5 mm indurations) was 99%, 94%, and 70% for areas with ZCL, ACL, and ZVL, respectively. Our data indicate that the LST is significantly more sensitive than IFN-γ levels in persons who have been cured of cutaneous leishmaniasis than in persons who have been cured of ZVL.