Gender-based medicine is an innovative branch of biomedical research and represents a new perspective for the future of health research. Many studies have been published on gender medicine in adults but very few data regarding children are available. A literature search covering articles published between 1stJuly, 2006 and 1st February, 2017 and concerning children only was conducted using multiple keywords and standardized terminology in Pubmed database. The search was limited to English-language publications. All relevant articles on endocrines, neurological, psychiatric, gastrointestinal, immunological, oncological, rheumatic, pneumological disorders, infectious diseases and analgesia were evaluated and pertinent articles were included in this review. Most of the available studies on gender disparity in childhood are about endocrine and neuro-psychiatric disorders, while there are few data in other areas of medicine. Even if several studies on pediatric gender differences can be found on literature, few of them move forwards to analyze the reasons of the observed diversity. No data on pharmacokinetic and pharmacodynamic differences between boys and girls can be found. Hence, more efforts should be directed to investigate these topics in childhood.

Staphylococcus aureus is an opportunistic pathogen and a leading cause of nosocomial infections. It can acquire resistance to all the antibiotics that entered the clinics to date, and the World Health Organization defined it as a high-priority pathogen for research and development of new antibiotics. A deeper understanding of the genetic variability of S. aureus in clinical settings would lead to a better comprehension of its pathogenic potential and improved strategies to contrast its virulence and resistance. However, the number of comprehensive studies addressing clinical cohorts of S. aureus infections by simultaneously looking at the epidemiology, phylogenetic reconstruction, genomic characterisation, and transmission pathways of infective clones is currently low, thus limiting global surveillance and epidemiological monitoring. We applied whole-genome shotgun sequencing (WGS) to 184 S. aureus isolates from 135 patients treated in different operative units of an Italian paediatric hospital over a timespan of 3 years, including both methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) from different infection types. We typed known and unknown clones from their genomes by multilocus sequence typing (MLST), Staphylococcal Cassette Chromosome mec (SCCmec), Staphylococcal protein A gene (spa), and Panton-Valentine Leukocidin (PVL), and we inferred their whole-genome phylogeny. We explored the prevalence of virulence and antibiotic resistance genes in our cohort, and the conservation of genes encoding vaccine candidates. We also performed a timed phylogenetic investigation for a potential outbreak of a newly emerging nosocomial clone. The phylogeny of the 135 single-patient S. aureus isolates showed a high level of diversity, including 80 different lineages, and co-presence of local, global, livestock-associated, and hypervirulent clones. Five of these clones do not have representative genomes in public databases. Variability in the epidemiology is mirrored by variability in the SCCmec cassettes, with some novel variants of the type IV cassette carrying extra antibiotic resistances. Virulence and resistance genes were unevenly distributed across different clones and infection types, with highly resistant and lowly virulent clones showing strong association with chronic diseases, and highly virulent strains only reported in acute infections. Antigens included in vaccine formulations undergoing clinical trials were conserved at different levels in our cohort, with only a few highly prevalent genes fully conserved, potentially explaining the difficulty of developing a vaccine against S. aureus. We also found a recently diverged ST1-SCCmecIV-t127 PVL− clone suspected to be hospital-specific, but time-resolved integrative phylogenetic analysis refuted this hypothesis and suggested that this quickly emerging lineage was acquired independently by patients. Whole genome sequencing allowed us to study the epidemiology and genomic repertoire of S. aureus in a clinical setting and provided evidence of its often underestimated complexity. Some virulence factors and clones are specific of disease types, but the variability and dispensability of many antigens considered for vaccine development together with the quickly changing epidemiology of S. aureus makes it very challenging to develop full-coverage therapies and vaccines. Expanding WGS-based surveillance of S. aureus to many more hospitals would allow the identification of specific strains representing the main burden of infection and therefore reassessing the efforts for the discovery of new treatments and clinical practices.

Serratia marcescens represents an important pathogen involved in hospital acquired infections. Outbreaks are frequently reported and are difficult to eradicate. The aim of this study is to describe an outbreak of Serratia marcescens occurred from May to November 2012 in a neonatal intensive care unit, to discuss the control measures adopted, addressing the role of molecular biology in routine investigations during the outbreak. After an outbreak of Serratia marcescens involving 14 neonates, all admitted patients were screened for rectal and ocular carriage every two weeks. Extensive environmental sampling procedure and hand sampling of the staff were performed. Antimicrobial susceptibility pattern and molecular analysis of isolates were carried out. Effective hand hygiene measures involving all the external consultants has been implemented. Colonized and infected babies were cohorted. Dedicated staff was established to care for the colonized or infected babies. During the surveillance, 65 newborns were sampled obtaining 297 ocular and rectal swabs in five times. Thirty-four Serratia marcescens isolates were collected: 11 out of 34 strains were isolated from eyes, being the remaining 23 isolated from rectal swabs. Two patients presented symptomatic conjunctivitis. Environmental and hand sampling resulted negative. During the fifth sampling procedure no colonized or infected patients have been identified. Two different clones have been identified. Ocular and rectal colonization played an important role in spread of infections. Implementation of infection control measures, involving also external specialists, allowed to control a serious Serratia marcescens outbreak in a neonatal intensive care unit.

The spread of carbapenem-resistant Enterobacteriaceae (CRE) is a health problem of major concern. CRE-related infections have significant morbidity and mortality, but data on CRE infection in pediatric population are limited. The aim of this study was to analyze epidemiologic and clinical characteristics, risk factors, therapeutic options and outcome of CRE infections in children in Italy. We performed a retrospective, multicenter, observational study of children with confirmed CRE infection or colonization admitted between January 1, 2011, and March 1, 2014, to 7 Italian pediatric centers. Sixty-nine patients presenting 74 CRE infections and/or colonization were included. The most frequently isolated strain was Klebsiella pneumoniae carbapenemase-producing K. pneumoniae. Children with CRE infections had longer length of stay in hospital (P < 0.001), duration of disease (P = 0.001) and antimicrobial treatment (P < 0.001) than colonized children. Oncologic/immunosuppressive conditions are one of the factors significantly associated with a fatal outcome among children with CRE infections. Our study confirms that CRE infections affect mostly children with oncologic diseases and immunosuppression. Controlled studies in large cohorts are needed to evaluate the best therapeutic options and to assess further risk factors influencing outcomes and the survival of pediatric patients with infections caused by CRE.

Antimicrobials are the most commonly prescribed drugs. Many studies have evaluated antibiotic prescriptions in the paediatric outpatient but few studies describing the real antibiotic consumption in Italian children’s hospitals have been published. Point-prevalence survey (PPS) has been shown to be a simple, feasible and reliable standardized method for antimicrobials surveillance in children and neonates admitted to the hospital. In this paper, we presented data from a PPS on antimicrobial prescriptions carried out in 7 large Italian paediatric institutions. A 1-day PPS on antibiotic use in hospitalized neonates and children was performed in Italy between October and December 2012 as part of the Antibiotic Resistance and Prescribing in European Children project (ARPEC). Seven institutions in seven Italian cities were involved. The survey included all admitted patients less than 18 years of age present in the ward at 8:00 am on the day of the survey, who had at least one on-going antibiotic prescription. For all patients data about age, weight, underlying disease, antimicrobial agent, dose and indication for treatment were collected. The PPS was performed in 61 wards within 7 Italian institutions. A total of 899 patients were eligible and 349 (38.9%) had an on-going prescription for one or more antibiotics, with variable rates among the hospitals (25.7% - 53.8%). We describe antibiotic prescriptions separately in neonates ( = 30 days to <18 years old). In the neonatal cohort, 62.8% received antibiotics for prophylaxis and only 37.2% on those on antibiotics were treated for infection. Penicillins and aminoglycosides were the most prescribed antibiotic classes. In the paediatric cohort, 64.4% of patients were receiving antibiotics for treatment of infections and 35.5% for prophylaxis. Third generation cephalosporins and penicillin plus inhibitors were the top two antibiotic classes. The main reason for prescribing antibiotic therapy in children was lower respiratory tract infections (LRTI), followed by febrile neutropenia/fever in oncologic patients, while, in neonates, sepsis was the most common indication for treatment. Focusing on prescriptions for LRTI, 43.3% of patients were treated with 3rd generation cephalosporins, followed by macrolides (26.9%), quinolones (16.4%) and carbapenems (14.9%) and 50.1% of LRTI cases were receiving more than one antibiotic. For neutropenic fever/fever in oncologic patients, the preferred antibiotics were penicillins with inhibitors (47.8%), followed by carbapenems (34.8%), aminoglycosides (26.1%) and glycopeptides (26.1%). Overall, the 60.9% of patients were treated with a combination therapy. Our study provides insight on the Italian situation in terms of antibiotic prescriptions in hospitalized neonates and children. An over-use of third generation cephalosporins both for prophylaxis and treatment was the most worrisome finding. A misuse and abuse of carbapenems and quinolones was also noted. Antibiotic stewardship programs should immediately identify feasible targets to monitor and modify the prescription patterns in children’s hospital, also considering the continuous and alarming emergence of MDR bacteria.