Outbreak of invasive Group A streptococcus disease in a nursing home in Ireland in February 2023 caused by emm type 18.

An out-of-season increase in cases of invasive Group A streptococcus (iGAS) was observed in Ireland between October 2022 and August 2023. We describe the management of an iGAS outbreak involving three nursing home residents in Ireland in early 2023. A regional Department of Public Health was notified of an iGAS case in a nursing home resident in January 2023. When two further cases among residents were notified 7 days later, an outbreak was declared. Surveillance for GAS/iGAS infection in residents and staff was undertaken. The site was visited to provide infection prevention and control (IPC) support. Isolates were emm typed. A total of 38 residents and 29 staff in contact with resident cases were provided with antibiotic chemoprophylaxis. Seven additional staff with no direct resident contact also received chemoprophylaxis after finding one probable localised GAS infection among them. No more iGAS cases subsequently occurred.Site visit recommendations included advice on terminal cleaning and cleaning of shared equipment, as well as strengthening staff education on hand hygiene and masking. All isolates were of emm subtype 18.12, a subtype not previously detected in Ireland. Key outbreak control measures were rapid delivery of IPC support and chemoprophylaxis. Emm18 is infrequently associated with GAS infections.

In severe acute kidney injury, a higher serum creatinine is paradoxically associated with better patient survival.

Lack of precise, reliable and consistent measures of kidney dysfunction in acute kidney injury (AKI) causes uncertainty in the definition and management of this important condition and interferes with treatment standardization. Serum creatinine (SCr) remains a key determinant in the management of renal dysfunction. In disparate populations, previous authors suggested a paradoxical association between higher SCr and better survival. We set out to analyse the association between SCr at start of continuous renal replacement therapy (CRRT) and survival, and to postulate possible mechanisms for this association. We hypothesized that in this setting, the association of higher SCr with better survival may be determined by better nutrition, lesser volume overload or pre-existing chronic kidney disease (CKD). In multivariable logistic regression analysis utilizing multiple imputation parameter estimates, a higher SCr on admission and initiation of CRRT was monotonically associated with better survival (OR 1.438, 95% CI 1.034-1.999) controlling for selected covariates. Nutrition and volume adjustments did not affect the significance of SCr. Adjustment of the model by degree of admission CDK (MDRD formula) and severity of disease (Liano scores) respectively decreased or abolished the significance of SCr levels. In univariate analysis, larger weight gains and lower urine outputs were correlated with lower SCr. In this population of critically ill, virtually anuric patients with AKI, possible explanations of this counterintuitive association include first, that a higher SCr at start of CRRT is related to pre-existing CKD. CKD patients may require a lesser burden of disease to reach the point where CRRT is needed, and therefore have a better survival. Inversely, a lower SCr may be an indication of fluid overload, associated with worse survival. Our findings did not support a role of nutrition or muscle mass for this association. All these possibilities are worthy of thorough investigation, as findings will likely result in important changes in patient outcome.