Bacterial causative agents of neonatal sepsis and their antibiotic susceptibility in neonatal intensive care units (Nicus) and neonatal wards in Iran: A systematic review

Context: Sepsis is one of the most common causes of neonatal mortality, especially in developing countries. The purpose of this study was to systematically review the bacterial causative agents of neonatal sepsis and their antibiotic susceptibility in Iran. Material and Methods: We searched all previously published papers to gather related information on Iranian neonatal sepsis in international and national databases (in both Persian and English) from 2006 to 2018. The standard STROBE checklist was used for quality assessment. The data were analyzed by statistical methods with a random-effects model using Stata 14 software. Results: A total of 89,472 neonates with sepsis (presented in 17 studies) were included in this systematic review. The mortality rate of neonates was 28.0. The proportions of neonatal sepsis caused by Gram-negative and Gram-positive bacteria were 66.0 and 33.0, respectively. The most common bacteria causing neonatal sepsis were Klebsiella pneumoniae and Pseudomonas aeruginosa (Gram-negative) and coagulase-negative staphylococci and Staphylococcus aureus (Gram-positive). Conclusions: Gram-negative bacteria are the most common causes of neonatal sepsis in Iran. Imipenem is the most effective antibiotic against Gram-negative bacilli and vancomycin against Gram-positive cocci causing neonatal sepsis in Iran. © 2020, Author(s)

B Cell Epitopes of Four Fimbriae Antigens of Klebsiella pneumoniae: A Comprehensive In Silico Study for Vaccine Development

Klebsiella pneumoniae is one of the major causes of nosocomial infections worldwide which can cause several diseases in children and adults. The globally dissemination of hyper-virulent strains of K. pneumoniae and the emergence of antibiotics-resistant isolates of this pathogen narrows down the treatment options and has renewed interest in its vaccines. Vaccine candidates of Klebsiella pneumoniae have not been adequately protective, safe and globally available yet. In K. pneumoniae infection, it is well known that B cells that induce robust humoral immunity are necessary for the host complete protection. Identifying the B cell epitopes of antigens is valuable to design novel vaccine candidates. In the present study using immunoinformatics approaches we found B cell epitopes of four K. pneumoniae type 1 fimbriae antigens namely FimA, FimF, FimG, and FimH. Linear and conformational B cell epitopes of each antigen were predicted using different programs. Subsequently, many bioinformatics assays were applied to choose the best epitopes including prediction antigenicity, toxicity, human similarity and investigation on experimental records. These assays resulted in final four epitopes (each for one Fim protein). These final epitopes were modeled and their physiochemical properties were estimated to be used as potential vaccine candidates. Altogether, we found four B cell epitopes of K. pneumoniae Fim antigens that are immunogen, antigenic, not similar to human peptides, not allergen and not toxic. Also, they have suitable physiochemical properties to administrate as vaccine, although their complete efficacy should be also shown in vitro and in vivo. © 2020, Springer Nature B.V