Several microorganisms produce nosocomial infections (NIs), among which Pseudomonas aeruginosa stands out as an opportunist pathogen with the capacity to develop multiresistance to first-choice antibiotics. From 2007 to 2013, forty-six NIs produced by P. aeruginosa were detected at a pediatric tertiary care hospital in Mexico with a significant mortality rate (17.39%). All isolates (n = 58/46 patients) were characterized by evaluating their response to several antibiotics as panresistant (PDR), extensively resistant (XDR), multiresistant (MDR) or sensitive (S). In addition, all isolates were typified through multilocus sequencing of seven genes: acsA, aroE, guaA, mutL, nuoD, ppsA and trpE. Furthermore, to establish the genetic relationships among these isolates, we carried out a phylogenetic inference analysis using maximum likelihood to construct a phylogenetic network. To assess evolutionary parameters, recombination was evaluated using the PHI test, and the ratio of nonsynonymous to synonymous substitutions was determined. Two of the strains were PDR (ST1725); 42 were XDR; four were MDR; and ten were S. Twenty-one new sequence types were detected. Thirty-three strains exhibited novel sequence type ST1725. The ratio of nonsynonym to synonym substitutions was 1:1 considering all genes. Phylogenetic analysis showed that the genetic relationship of the PDR, XDR and MDR strains was mainly clonal; however, the PHI test and the phylogenetic network suggest that recombination events occurred to produce a non-clonal population. This study aimed not only to determine the genetic diversity of clinical P. aeruginosa but also to provide a warning regarding the identification and spreading of clone ST1725, its ability to cause outbreaks with high mortality rates, and to remain in the hospital environment for over seven years. These characteristics highlight the need to identify clonal outbreaks, especially where high resistance to most antibiotics is observed, and control measures are needed. This study also represents the first report of the PDR ST1725.

Introduction: Healthcare-associated infections are an important cause of morbidity and mortality, are among the most common adverse events in healthcare, and of them, pneumonia is the most commonly reported. Our objective was to evaluate the incidence and clinical outcome of respiratory viruses in hospital-acquired pneumonia (HAP). Methods: This was a prospective cohort study, include patients aged between 0 and 18 who fulfilled Centers for Diseases Control and Prevention (CDC) criteria for HAP. Demographic and clinical data were obtained, and a nasopharyngeal swab specimen was taken for the detection of respiratory viruses. All included patients were monitored until discharge to collect data on the need for mechanical ventilation, intensive care unit (ICU) admission, and mortality. All-cause 30-day mortality was also ascertained. Results: Four thousand three hundred twenty-seven patients were followed for 42,658 patient-days and 5,150 ventilator-days. Eighty-eight patients (2.03%) met the CDC criteria for HAP, 63 patients were included, and clinical and epidemiological characteristics showed no statistically significant differences between patients with virus associated healthcare-associated pneumonia (VAHAP) and those with non-viral healthcare-associated pneumonia (NVHAP). At least one respiratory virus was detected in 65% [95% CI (53–77)] of episodes of HAP, with a single viral pathogen observed in 53.9% and coinfection with 2 viruses in 11.1% of cases. The outcome in terms of ICU admission, mechanical ventilation and the 30-day mortality did not show a significant difference between groups. Conclusions: In two-thirds of the patients a respiratory virus was identified. There was no difference in mortality or the rest of the clinical outcome variables. About half of the patients required mechanical ventilation and 10% died, which emphasizes the importance of considering these pathogens in nosocomial infections, since their identification can influence the decrease in hospital costs and be taken into account in infection control policies.

IntroductionHealthcare personnel (HP) are frequently exposed to influenza and can be a source of transmission to patients and other workers, resulting in high‐cost outbreaks for healthcare institutions.ObjectivesTo analyse the presentation of HP with influenza‐like illness (ILI) and the differences between individuals with influenza confirmed by polymerase chain reaction (PCR) and those with a negative test. The secondary objective was to evaluate the duration of symptomatology and work absenteeism as well as the vaccination rate of HP at a paediatric referral hospital.MethodsA cross‐sectional, descriptive study was conducted at a paediatric referral hospital. Clinical and epidemiological data on HP with ILI were collected between January and April 2016. Nasopharyngeal swab for influenza PCR was obtained from one in every three workers with ILI. Telephone follow‐up was conducted to document duration of symptoms, complications and absenteeism.ResultsA total of 164 ILI episodes were evaluated in 162 HP. A swab was obtained in 59 cases, and influenza was detected in 30 cases. The clinical picture of HP with confirmed influenza was similar to that of HP with a negative PCR. Arthralgia was more common in those with influenza (90% vs 58%), with a tendency towards statistical significance. No HP required hospitalization, and 78.5% were absent from work at least 1 day.ConclusionsInfluenza causes significant morbidity and absenteeism among HP. Influenza infection was confirmed in only half of HP with an ILI on whom a PCR was performed, suggesting that other respiratory viruses can cause a similar pattern.

Rheumatoid arthritis (RA) is the most common form of inammatory arthropathy sustained by autoimmune responses. This review has the objective of updating the knowledge about RA especially its molecular pathogenesis. We examine here the current knowledge of tryptophan, arginine, homoarginine and histidine metabolism and the main immunoregulatory pathways in amino acid catabolism in both RA patients and experimental models of arthritis. Of the characteristic autoantibodies of RA, those that appear earlier, are those that recognize cyclic citrullinated peptides. (CCP) and/or citrullinated brinogen. Therefore our analysis would indicate that amino acids metabolism represents a fruitful area of research for new drug targets for a more effective and safe therapy of RA.

Cortactin and HS1 are actin‐binding molecules known to be overexpressed in leukemic B‐cells from adult patients with chronic lymphoid leukemia. Both proteins are required for proper actin remodeling in virtually all cell types. While cortactin overexpression is associated to invasiveness of various solid tumor cells, HS1 is correlated with poor prognosis of chronic leukemia in adult patients. However, the role of cortactin and HS1 in childhood acute lymphoblastic leukemias (ALL) has never been studied. Here, we analyzed mRNA levels of both cortactin and HS1 in model cell lines for ALL and primary bone marrow (BM) cells from B‐ALL patients, and found substantial increases for both cortactin and HS1 in leukemic cells compared to controls. Furthermore, protein levels of cortactin were highest within primary primitive Lin‐CD34+ stem and progenitor cell compartments, while lineage committed CD34‐CD19+ and non‐B cells displayed low expression levels. By contrast, HS1 expression was high but did not change during differentiation. Unraveling the importance of differential expression of cortactin and HS1 in leukemia initiating cells for the population dynamics and development of childhood acute leukemias may open novel treatment strategies to prevent progression of the disease with infiltrations into other organs.