Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Strongyloidiasis: Really a Zoonosis?

More than 600 million people are estimated to be infected with the nematode Strongyloides stercoralis, which is often overlooked during routine parasitological diagnostics. Some of the young worms mature to infective larvae within the host, enabling this parasite to establish long-lived, self-sustaining infections. While most of these infections are mild, they can self-enhance, resulting in complicated strongyloidisas, which if not treated in time, is normally lethal. While it is undisputed that dogs are susceptible to experimental infection with human-derived S. stercoralis, it has long been debated if Strongyloides sp. naturally found in dogs are human infective S. stercoralis or belong to a different species, S. canis. Based on recent studies, I argue that dogs naturally carry S. stercoralis, in addition to at least one other species, for which we have no indication that it infects people. I argue that for all practical purposes of S. stercoralis treatment and prevention, dogs should be seriously considered as possible sources for human S. stercoralis. However, from a rigorous scientific point of view, we must admit that currently we have no idea about the relative importance of zoonotic transmission compared with human to human transmission