Control of Paneth cell function by HuR regulates gut mucosal growth by altering stem cell activity

Rapid self-renewal of the intestinal epithelium requires the activity of intestinal stem cells (ISCs) that are intermingled with Paneth cells (PCs) at the crypt base. PCs provide multiple secreted and surface-bound niche signals and play an important role in the regulation of ISC proliferation. Here, we show that control of PC function by RNA-binding protein HuR via mitochondria affects intestinal mucosal growth by altering ISC activity. Targeted deletion of HuR in mice disrupted PC gene expression profiles, reduced PC-derived niche factors, and impaired ISC function, leading to inhibited renewal of the intestinal epithelium. Human intestinal mucosa from patients with critical surgical disorders exhibited decreased levels of tissue HuR and PC/ISC niche dysfunction, along with disrupted mucosal growth. HuR deletion led to mitochondrial impairment by decreasing the levels of several mitochondrial-associated proteins including prohibitin 1 (PHB1) in the intestinal epithelium, whereas HuR enhanced PHB1 expression by preventing microRNA-195 binding to the Phb1 mRNA. These results indicate that HuR is essential for maintaining the integrity of the PC/ISC niche and highlight a novel role for a defective PC/ISC niche in the pathogenesis of intestinal mucosa atrophy.

WSES guidelines for management of Clostridium difficile infection in surgical patients

In the last two decades there have been dramatic changes in the epidemiology of Clostridium difficile infection (CDI), with increases in incidence and severity of disease in many countries worldwide. The incidence of CDI has also increased in surgical patients. Optimization of management of C difficile, has therefore become increasingly urgent. An international multidisciplinary panel of experts prepared evidenced-based World Society of Emergency Surgery (WSES) guidelines for management of CDI in surgical patients.

Clostridium difficile infection: update on diagnosis, epidemiology, and treatment strategies

BACKGROUND

Clostridium difficile infection (CDI) has increased in incidence and severity over the past quarter century, and is now considered a major cause of healthcare-associated infections.

METHODS

Review of the pertinent English-language medical literature.

RESULTS

There has been a substantial change in the management of CDI. The emergence of the NAP1/BI/O27 strain in the early to mid-2000s has been associated with more severe forms of CDI. The pathophysiology, epidemiology, clinical manifestations and diagnosis, as well as new strategies for medical and surgical management are discussed in this review.

CONCLUSIONS

Clostridium difficile infection can range from benign diarrhea to severe disease associated with substantial morbidity and mortality. Treatment modalities vary based on disease severity and timing of onset. The mainstay of medical treatment remains metronidazole and oral/rectal vancomycin. New management strategies are evolving, including adjunctive treatments such as monoclonal antibodies, vaccination, and fecal transplant. In patients with severe disease or clinical deterioration, early surgical consultation for total colectomy or loop ileostomy may be life-saving. Infection control measures are vital to mitigating the spread of CDI.

Emergent versus elective cholecystectomy: conversion rates and outcomes

BACKGROUND

Laparoscopic cholecystectomy (LC) is the procedure of choice for treatment of cholelithiasis/cholecystitis. Conversion rates (CR) to open cholecystectomy (OC) have been reported previously as 5-15% in elective cases, and up to 25% in patients with acute cholecystitis. We examined the CR in a tertiary-care academic hospital and a statewide surgery quality collaborative, and to compare complications and outcomes in elective and emergency cholecystectomy.

METHODS

Prospective data were obtained from: 1) Non-Trauma Emergency Surgery (NTE) database of all emergent cholecystectomies 1/1/2008-12/31/2009; and 2) Michigan Surgical Quality Collaborative (MSQC) database with a random sample of 20-30% of all operations performed 1/1/2005-12/31/2010, including both University of Michigan (UM) data and statewide data from 34 participating hospitals. Patient characteristics, CR, and outcomes were compared for emergent vs. elective cases.

RESULTS

Non-trauma ES patients had a mean hospital length of stay (HLOS) of 4.9 d. Open cholecystectomy-HLOS was greater (4.0, LC; 7.9 laparoscopic converted to open cholecystectomy; 8.7, OC, p<0.0001); mortality was 0.35% and CR was 17.5%. In the UM-MSQC dataset, OC-HLOS was greater (6.8 OC vs. 4.6 LC, p<0.001); mortality was 0.65%; CR was 9.1% in elective cases and 14.9% in emergent cases. CR was almost two-fold higher [17.5% of all NTE cholecystectomies vs. 9.1% of UM-MSQC elective cholecystectomies (p=0.00078)]. The statewide MSQC cholecystectomy data showed significantly increased HLOS in emergent cholecystectomy patients (4.34 vs. 2.65 d; p<0.0001). Morbidity (8.8 vs. 3.7%) and mortality (2.6 vs. 0.5%) rates were also significantly higher in emergent vs. elective cholecystectomies (p<0.0001).

CONCLUSION

In NTE patients requiring cholecystectomy, CR is almost two-fold higher but is lower than in reports published previously (25%). However, there is a wide variability in mortality and morbidity for emergency cholecystectomy in both unadjusted and risk-adjusted analyses. Further studies are required to determine modifiable risk factors to improve outcomes in emergency cholecystectomy.

Common complications in the critically ill patient

Critically ill patients in intensive care units are subject to many complications associated with therapy. Many of these complications are health care-associated infections and are related to indwelling devices, including ventilator-associated pneumonia, central line-associated bloodstream infection, catheter-associated urinary tract infection; surgical site infection, venous thromboembolism, deep venous thrombosis, and pulmonary embolus are other common complications. All efforts should be undertaken to prevent these complications in surgical critical care, and national efforts are under way for each of these complications. In this article, epidemiology, risk factors, diagnosis, treatment, and prevention of these complications in critically ill patients are discussed.