Pharmacology of the internal anal sphincter and its relevance to faecal incontinence

1 The internal anal sphincter (IAS) has a spontaneous tone and is the main contributor to the maintenance of faecal continence. The spontaneous resting tone exhibited by the sphincter can be modified by neurotransmitters from the autonomic and enteric nervous systems. 2 In this review, the influence of the sympathetic and parasympathetic nervous systems on IAS tone are discussed and the putative roles of nitric oxide, carbon monoxide, vasoactive intestinal peptide and adenosine triphosphate in non‐adrenergic non‐cholinergic transmission are considered. 3 Faecal incontinence is a common condition that places a heavy financial burden on the health service and severely affects patients’ quality of life. Resting anal pressure is reduced in patients with faecal incontinence and agents that increase sphincter tone tend to relieve symptoms. The results of clinical studies of the use of phenylephrine to treat faecal incontinence are reviewed. 4 It is concluded that the IAS is a potential target for drug development for the treatment of faecal incontinence.     

The shape of stress: the use of frequent sampling to measure temporal variation in S‐IgA levels during acute stress

Previous studies have indicated that statistically significant increases in Secretory immunoglobulin A (S‐IgA) can be achieved in as little as 5min as a result of mental stress. However, the temporal resolution of these changes is low and therefore the rate and pattern of changes during the stress task and during subsequent recovery is unclear. A within‐subjects design was used to examine levels of S‐IgA before, during and after a short (8 min) mental stress task. S‐IgA was measured from saliva samples obtained every 2 min during the entire 30‐min session. Significant increases in S‐IgA concentration were observed as early as the task instruction period, with additional increases during the stress task itself. The data also show a rapid recovery of S‐IgA, with a return to baseline levels within 6 min. Results suggest that S‐IgA changes can occur very rapidly and that the observed increases are short‐lived. Copyright © 2007 John Wiley & Sons, Ltd.     

Mechanical Testing of Seven Fixation Methods for Generation of Compression Across a Midtarsal Osteotomy: A Comparison of Internal and External Fixation Devices

The purpose of this study was to assess 7 methods of fixation for a midtarsal osteotomy. Polyurethane foam models (N = 6) and cadaver specimens (N = 4-7) were used to examine the force generated by the different constructs of fixation. A midtarsal osteotomy was performed on each specimen in the test groups. The osteotomies were fixated either with 2 parallel 0.062-in Kirschner wires and 40-mm-long, 4-mm partially threaded, cancellous, cannulated titanium screws, an external ring fixator (frame), a frame with wires tensioned (tension), a frame with wires tensioned and compressed toward the osteotomy (tension and compression), a frame with tension, compression, and parallel Kirschner wires, or a frame with tension, compression, and two 4.0 cannulated parallel screws, respectively. Each model was fixated, and the force generated by the construct across the osteotomy was recorded via the use of pressure-sensitive film. Statistical analysis of the data in the polyurethane foam group determined that the use of frame with tension, compression, and two 4.0 parallel cannulated screws was statistically superior to 1) frame, 2) frame with tension, 3) 2 parallel Kirschner wires, 4) two 4.0 cannulated parallel screws, and 5) frame with tension and compression. A cadaver study determined that the frame with tension, compression, and 2 parallel Kirschner wires was statistically superior to 1) frame and 2) two parallel Kirschner wires. These findings suggest that there is a difference in the force generated by the type of fixation construct across a midtarsal osteotomy.     

ES05ROUTINE PARAFIBROMIN IMMUNOHISTOCHEMISTRY OF LARGE PARATHYROID ADENOMAS IS NOT AN EFFECTIVE SCREENING STRATEGY FOR CARCINOMA

Purpose Parathyroid carcinoma (PC) is rare and accounts for less than 1% of all cases of primary hyperparathyroidism (PHPT). The definitive histopathologic diagnosis of PC requires unequivocal invasion or metastasis which may be absent at first presentation. As a result, many cases of PC can only be diagnosed retrospectively. Parafibromin is the protein encoded by HRPT2 which is mutated and not expressed in many parathyroid carcinomas. Given that PCs generally weigh more than parathyroid adenomas (PA)s, we hypothesized that amongst large PAs there may be a high incidence of occult PC which could be identified by negative staining for parafibromin. Methodology 57 parathyroid glands weighing greater than 2 grams excised from 1998–2006 were identified from the University of Sydney Endocrine Surgical Database. Two specimens with a histopathologic diagnosis of PC were excluded. Immunohistochemical staining for parafibromin was performed on the remaining 55 PAs. Results Of the 55 specimens stained for parafibromin only one definite negative stain was detected. This case was originally classified as an “atypical adenoma” because it showed nuclear and architectural atypia without unequivocal evidence of invasive growth. In view of the negative staining for parafibromin it therefore probably represents occult carcinoma. There has been no evidence of recurrence or metastasis after 6.5 years. Conclusions Complete loss of staining for parafibromin is very rare in giant parathyroid adenomas suggesting that occult carcinoma is equally rare. As a result routine immunohistochemical staining for parafibromin does not appear to be an effective screening test for carcinoma in large PA without histopathologic features of PC.     

HP26PSEUDO‐ACHALASIA FOLLOWING A SLIPPED LAPAROSCOPICALLY PLACED ADJUSTABLE GASTRIC BAND: A CASE REPORT

Purpose To demonstrate that laparoscopic adjustable gastric banding may promote oesophageal dilatation or interfere with oesophageal motility. Methodology We report a case of a 67 year old female with a complex medical history who developed secondary achalasia from a slipped laparoscopic adjustable gastric band for weight loss. This led to recurring episodes of aspiration pneumonia requiring multiple admissions at North Shore Hospital, Auckland, New Zealand. Results A decision was made to remove the gastric band, five years after its initial insertion. At one month follow up, she was swallowing normally and oesophageal manometry had returned to normal. Conclusion Oesophageal dysmotility is sometimes seen in patients who have bands that are adjusted too tightly or in whom the band has slipped. This can lead to serious complications if unrecognized and incorrectly treated. Oesophageal symptoms in patients with adjustable bands must be considered secondary to the band until proven otherwise ie removal of the band or complete deflation.     

The health-related quality of life of male and female heavy smokers

Objectives: Heavy smokers are a segment of the smoking population who are at increased risk of smoking-related morbidity and least likely to achieve cessation. This study identifies the impact of heavy smoking on quality of life by gender and describes the subpopulation for improved targeting.Methods: South Australian representative population data (n = 3010) was used to compare the health-related quality of life status of male and female heavy smokers as assessed by the SF-36.