Objectives: To review the current literature on the presence of COVID-19 virus in the urine of infected patientsand to explore the clinical features that can predict the presence of COVID-19 in urine.Materials and Methods: A systematic review of published literature between 30th December 2019 and 21st June2020 was conducted on Pubmed, Google Scholar, Ovid, Scopus, and ISI web of science. Studies investigatingurinary viral shedding of COVID-19 in infected patients were included. Two reviewers selected relative studiesand performed quality assessment of individual studies. Meta-analysis was performed on the pooled case reportsand cohort with a sample size of ≥ 9.Results: Thirty-nine studies were finally included in the systematic review; 12 case reports, 26 case series, andone cohort study. Urinary samples from 533 patients were investigated. Fourteen studies reported the presenceof COVID-19 in the urinary samples from 24 patients. The crude overall rate of COVID-19 detection in urinarysamples was 4.5%. Considering case series and cohorts with a sample size of ≥ 9, the estimated viral sheddingfrequency was 1.18 % (CI 95%: 0.14 – 2.87) in the meta-analysis. Urinary viral load in most reports were lowerthan rectal or oropharyngeal samples. In adult patients, urinary shedding of COVID-19 was commonly detectedin patients with moderate to severe disease (16 adult patients with moderate or severe disease versus two adultpatients with mild disease). In children, urinary viral shedding of COVID-19 was reported in 4 children who allsuffered from mild disease. Urinary viral shedding of COVID-19 was detected from day 1 to day 52 after diseaseonset. The pathogenicity of virus isolated from urine has been demonstrated in cell culture media in one studywhile another study failed to reveal replication of isolated viral RNA in cell cultures. Urinary symptoms were notattributed to urinary viral shedding.Conclusion: While COVID-19 is rarely detected in urine of infected individuals, infection transmission throughurine still remains possible. In adult patients, infected urine is more likely in the presence of moderate or severedisease. Therefore, caution should be exerted when dealing with COVID-19 infected patients during medical interventionslike endoscopy and urethral catheterization especially in symptomatic adult patients while in childrencaution should be exerted regardless of symptoms.

Background: β-Lactam antibiotics have been broadly used for the treatment of Acinetobacter baumannii infections, resulting in development of β-lactam inactivating β-lactamases. Here, we described antibiotic resistance rate, prevalence of β-lactamase-encoding genes, and clonal relationships of A. baumannii strains isolated from children referred to Children’s Medical Center in Tehran, Iran, during 2019–2020. Methods: A total of 60 non-replicate A. baumannii isolates were recovered from clinical specimens of pediatric patients. Antibiotic susceptibility testing was done by the disc diffusion method. Colistin susceptibility of isolates was performed by the broth microdilution method. β-lactamase-encoding genes were characterized by PCR. The presence of ISAba1 element upstream of the several oxacillinase genes was also checked. Genetic relatedness of isolates was determined by using random amplification of polymorphic DNA (RAPD) typing. Results: The antimicrobial susceptibility tests showed that 83.3% of A. baumannii isolates were MDR, and 40% XDR. Both MDR and XDR A. baumannii isolates were susceptible to colistin. The frequency of bla_OXA-51-like, bla_OXA-23-like, bla_TEM, bla_OXA-24-like, bla_PER, bla_SHV, bla_CTX-M, bla_OXA-58-like, and bla_IMP was 100, 93.33, 60, 36.67, 28.33, 8.33, 5, 3.33, and 1.67%, respectively. Coexistence of ISAba1/bla_OXA-23-like and ISAba1/bla_OXA-51-like was observed in 65% and 85% of isolates, respectively. RAPD analysis revealed 4 common types and 2 single types of A. baumannii isolates. Conclusions: The multiple clones harboring bla_OXA-23-like, ISAba1-bla_OXA-51-like, and ISAba1-bla_OXA-23-like were responsible for the spread of A. baumannii isolates in our clinical wards. Dissemination of the well-established clones is worrisome and would become therapeutic challenges due to the possible transferring genetic elements associated with resistance.

Background: Hepatitis B virus (HBV) infection is a major health problem worldwide. Objectives: The aim of this study was to investigate the frequency of occult hepatitis B infection (OBI) and its associated risk factors, together with the molecular characterization of the virus in injecting drug users of Tehran. Patients and Methods: The study consisted of 229 injecting drug users. Serum samples were collected and tested for the presence of hepatitis B core antibody (HBcAb) and hepatitis B surface antigen (HBsAg) by an enzyme-linked immunosorbent assay (ELISA). HBV B virus DNA was extracted from the serum samples, and a fragment of the S gene was amplified using the nested polymerase chain reaction. The genotype, subgenotypes, subtype, and S gene mutation of HBV were determined by direct sequencing. A phylogenetic tree was constructed using the neighbor-joining method. Results: Sixty-four (28%) participants were HBcAb positive, 59 cases were HBcAb positive and HBsAg negative, and 5 cases were HBsAg positive. Hepatitis B DNA was found in three HBsAg-positive cases. Thirteen of 59 (22%) individuals were hepatitis B DNA positive. The phylogenetic tree of hepatitis B DNA showed the existence of genotype D. The only significant correlation was between sharing a syringe and OBI. Conclusions: In comparison with the rate of HBcAb positivity reported in other Iranian studies, the rate was higher in the present study. There were a few variations, genotypes, and subtypes among the infected injecting drug users. Further investigations are needed to unravel the molecular characterization of OBI. Keywords: Injecting Drug User; Hepatitis B; Genotype; Hepatitis B Surface Antigen

Objectives: To review the current literature on the presence of COVID-19 virus in the urine of infected patients and to explore the clinical features that can predict the presence of COVID-19 in urine. Materials and Methods: A systematic review of published literature between 30 ^th December 2019 and 21 ^st June 2020 was conducted on Pubmed, Google Scholar, Ovid, Scopus, and ISI web of science. Studies investigating urinary viral shedding of COVID-19 in infected patients were included. Two reviewers selected relative studies and performed quality assessment of individual studies. Meta-analysis was performed on the pooled case reports and cohort with a sample size of 9. Results: Thirty-nine studies were finally included in the systematic review; 12 case reports, 26 case series, and one cohort study. Urinary samples from 533 patients were investigated. Fourteen studies reported the presence of COVID-19 in the urinary samples from 24 patients. The crude overall rate of COVID-19 detection in urinary samples was 4.5%. Considering case series and cohorts with a sample size of ≥ 9, the estimated viral shedding frequency was 1.18 % (CI 95%: 0.14 – 2.87) in the meta-analysis. In adult patients, urinary shedding of COVID-19 was commonly detected in patients with moderate to severe disease (16 adult patients with moderate or severe disease versus two adult patients with mild disease). In children, urinary viral shedding of COVID-19 was reported in 4 children who all suffered from mild disease. Urinary viral shedding of COVID-19 was detected from day 1 to day 52 after disease onset. The pathogenicity of virus isolated from urine has been demonstrated in cell culture media in one study while another study failed to reveal replication of isolated viral RNA in cell cultures. Urinary symptoms were not attributed to urinary viral shedding. Conclusions: While COVID-19 is rarely detected in urine of infected individuals, infection transmission through urine still remains possible. In adult patients, infected urine is more likely in the presence of moderate or severe disease. Therefore, caution should be exerted when dealing with COVID-19 infected patients during medical interventions like endoscopy and urethral catheterization.