Prostaglandin E2 receptors and their role in gastrointestinal motility - Potential therapeutic targets

Prostaglandin E₂ (PGE₂) is found throughout the gastrointestinal tract in a diverse variety of functions and roles. The recent discovery of four PGE₂ receptor subtypes in intestinal muscle layers as well as in the enteric plexus has led to much interest in the study of their roles in gut motility. Gut dysmotility has been implicated in functional disease processes including irritable bowel syndrome (IBS) and slow transit constipation, and lubiprostone, a PGE₂ derivative, has recently been licensed to treat both conditions. The diversity of actions of PGE₂ in the intestinal tract is attributed to its differing effects on its downstream receptor types, as well as their varied distribution in the gut, in both health and disease. This review aims to identify the role and distribution of PGE₂ receptors in the intestinal tract, and aims to elucidate their distinct role in gut motor function, with a specific focus on functional intestinal pathologies.

Incidental findings detected on emergency abdominal CT scans: a 1-year review

INTRODUCTION

In recent years, there has been a substantial rise in the use of computed tomography (CT) in the emergency medicine setting. Accordingly, with increased CT usage there has been an upsurge in incidental pathology detection.

METHODS

A retrospective review of all emergency CT abdominal scans performed at a university teaching hospital was examined. The frequency of incidental findings, their clinical significance and workload effect for the radiology department was assessed.

RESULTS

1155 patients had an emergency abdominal CT scan of which 700 had incidental findings detected. Of the incidental findings, 143 were deemed indeterminate requiring urgent investigations. Twenty-four occult neoplasms were confirmed subsequently. Additionally, 259 patients were recommended for additional diagnostics. The cumulative effect of the initial emergency abdominal CT was 15,015 relative value units (RVU). Subsequent imaging of incidental findings resulted in another 1674 RVU workload for radiology.

CONCLUSION

Incidental findings cause considerable debate and concern over which patients require significant follow-up, investigations, and/or surveillance. This exerts significant pressures on sub-specialties for their expert input, with increased workload and implications on healthcare service provision.

A Rare Case of BRCA2-Associated Breast Cancer in Pregnancy

A 30-year old woman was referred to our department with symptomatic breast cancer at 35 weeks gestation. Genetic testing revealed a pathogenic BRCA2 mutation. Labour was induced at 38 weeks. Mastectomy and axillary clearance were performed with a view to adjuvant chemotherapy, radiation and hormonal therapy. Multidisciplinary involvement is crucial for management of BRCA-associated breast cancer, especially in the context of pregnancy. Bilateral mastectomy may be indicated given the increased risk of ipsilateral and contralateral breast cancers. Tamoxifen may lower contralateral breast cancer risk in those in whom risk-reducing surgery is not performed.

An unusual cause for massive inflation

Chagas disease is a rare condition but with an increasing incidence. Megacolon is a known sequelae. Surgical management remains the only disease modifying treatment option; with variable long-term success. We highlight an interesting case to emphasize attention to this rare condition as a differential diagnosis in any patient presenting with massive intestinal dilatation.

Systematic review of preoperative, intraoperative and postoperative risk factors for colorectal anastomotic leaks

BACKGROUND

Anastomotic leak (AL) represents a dreaded complication following colorectal surgery, with a prevalence of 1-19 per cent. There remains a lack of consensus regarding factors that may predispose to AL and the relative risks associated with them. The objective was to perform a systematic review of the literature, focusing on the role of preoperative, intraoperative and postoperative factors in the development of colorectal ALs.

METHODS

A systematic review was performed to identify adjustable and non-adjustable preoperative, intraoperative and postoperative factors in the pathogenesis of AL. Additionally, a severity grading system was proposed to guide treatment.

RESULTS

Of 1707 papers screened, 451 fulfilled the criteria for inclusion in the review. Significant preoperative risk factors were: male sex, American Society of Anesthesiologists fitness grade above II, renal disease, co-morbidity and history of radiotherapy. Tumour-related factors were: distal site, size larger than 3 cm, advanced stage, emergency surgery and metastatic disease. Adjustable risk factors were: smoking, obesity, poor nutrition, alcohol excess, immunosuppressants and bevacizumab. Intraoperative risk factors were: blood loss/transfusion and duration of surgery more than 4 h. Stomas lessen the consequences but not the prevalence of AL. In the postoperative period, CT is the most commonly used imaging tool, with or without rectal contrast, and a C-reactive protein level exceeding 150 mg/l on day 3-5 is the most sensitive biochemical marker. A five-level classification system for AL severity and appropriate management is presented.

CONCLUSION

Specific risk factors and their potential correction or indications for stoma were identified. An AL severity score is proposed to aid clinical decision-making.

Minimally invasive and surgical management strategies tailored to the severity of acute diverticulitis

BACKGROUND

The severity of acute diverticulitis ranges from mild, simple inflammation to pericolic abscesses, or perforation with faeculent peritonitis. Treatment of diverticulitis has evolved towards more conservative and minimally invasive strategies. The aim of this review is to highlight recent concepts and advances in management.

METHODS

A literature review was performed on the electronic databases MEDLINE from PubMed, Embase and the Cochrane Library for publications in English. The keywords 'diverticulitis', 'diverticular' were searched for the past decade (to September 2013).

RESULTS

Diverticulitis occurs frequently in the Western world, but only one in five patients develops complications (such as abscess and perforation) during the first acute presentation. The reported perforation rate is 3.5 per 100,000 population. Based on recent data, including the AVOD and DIVER trials, antibiotic therapy for mild episodes may be unnecessary and outpatient management reasonable in most patients. Antibiotics and admission to hospital is required for complicated diverticulitis confirmed on imaging and for patients with sepsis. Diverticular abscesses (about 5 per cent of patients) may require percutaneous drainage if antibiotics alone fail. Laparoscopic management of non-faecal perforated diverticulitis is feasible in selected patients, and peritoneal lavage in combination with antibiotic therapy may avoid colonic resection and a stoma. However, the collective, published worldwide experience is limited to fewer than 800 patients, and results from ongoing randomized trials (LapLAND, SCANDIV, DILALA and LADIES trials) are needed to inform better decision-making.

CONCLUSION

The treatment of diverticulitis continues to evolve with a trend towards a more conservative and minimally invasive management approach. Judicious use of antibiotics in uncomplicated cases, greater application of laparoscopic techniques, and primary resection and anastomosis are of benefit in selected patients.

Clinical review: surgical management of locally advanced and recurrent colorectal cancer

AIM

Recurrent and locally advanced colorectal cancers frequently require en bloc resection of involved organs to achieve negative margins. The aim of this review is to evaluate the most current literature related to the surgical management of locally advanced and recurrent colorectal cancer.

METHODS

A literature review was performed on the electronic databases MEDLINE from PubMed, EMBASE and the Cochrane library for publications in the English language from January 1993 to July 2013. The MeSH search terms 'locally advanced colorectal cancer', 'recurrent colorectal cancer' and 'surgical management' were used.

RESULTS

A total of 1,470 patients with recurrent or locally advanced primary colorectal cancer were included in 22 studies. Surgical removal of the tumour with negative margins (R0) offers the best prognosis in term of survival with a 5-year survival of up to 70 %. MVR is needed in approximately 10 % with the most commonly involved organ being the bladder. The mean post-operative morbidity is 40 %, mainly relating to superficial surgical site infection, pelvic collections and delayed wound healing. Most patients will undergo radiotherapy and/or chemotherapy pre- or post-operatively. The mean 5-year overall survival for R0 resection is 50 % for recurrent and locally advanced primary tumours while survival following R1 or R2 is 12 and <5 %, respectively.

CONCLUSION

Multimodal therapy and extended surgery to achieve clear margins offers good prognosis to patients with recurrent and locally advanced colorectal cancers.