DIAGNOSTIC VALUE OF PLASMA AMYLASE, ESPECIALLY AFTER GASTRECTOMY

Pancreatitis following bariatric surgery

BACKGROUND

The laparoscopic Roux-en-Y gastric bypass (LRYGBP) is the second most performed bariatric surgical procedure. With the increasing number of patients undergoing bariatric surgery, the number of complications is also growing. Early diagnosis and treatment of the complications is crucial.

CASE PRESENTATION

A very unusual complication was met after an uneventful laparoscopic gastric bypass (LGBP) procedure due to an obstructing blood clot in the biliairy limb resulting in an acute pancreatitis and gastric distention, accompanied by an obstructing blood clot in the distal ileum causing small bowel obstruction. A review of the occurrence of these complications and the diagnosis and treatment is presented.

CONCLUSION

Post-bariatric acute pancreatitis is uncommon, but could be fatal. Blood clots should be considered as possible causes of small bowel obstruction, ileus or pancreatitis.

Elevated plasma pancreatic enzyme concentrations after Roux-en-Y gastric bypass may indicate closed loop obstruction

Laparoscopic Roux-en-Y gastric bypass is one of the most commonly performed bariatric procedures and most patients are women of reproductive age. Consequently, general surgeons and obstetricians need to be aware that these patients are at risk of bariatric specific surgical complications during their pregnancy. We report a case involving a 32-year-old woman who had undergone Roux-en-Y gastric bypass surgery 2 years previously. She presented at 25 weeks of gestation with a closed loop obstruction due to a retrograde jejunojejunal intussusception that was initially misdiagnosed as acute pancreatitis.

Roux-en-Y gastric bypass: hyperamylasemia is associated with small bowel obstruction

BACKGROUND

Small bowel obstruction after Roux-en-Y gastric bypass (RYGB) can be difficult to diagnose, but usually requires surgical treatment; clinical presentation may be nonspecific. Delay in diagnosis can result in catastrophic outcomes. Patients who present with small bowel obstruction after gastric bypass occasionally have pancreatic enzyme elevation and have been misdiagnosed as having acute pancreatitis. The objective of this study was to determine if there was an association between small bowel obstruction and an elevated amylase or lipase after RYGB.

METHODS

Ninety-nine cases of small bowel obstruction treated surgically were prospectively collected and retrospectively analyzed from a database of 4014 RYGB patients. Fifty-eight had a measurement of amylase or lipase at the time of operation.

RESULTS

An elevated amylase or lipase was found in 48% of all patients. These elevated rates were higher in an acute obstruction compared to those presenting with chronic symptoms (64% versus 28%; P=.007) and in obstruction involving the biliopancreatic limb compared to those that did not involve that limb (65% versus 21%; P<.001). These elevated rates were most notable in acute biliopancreatic limb obstruction compared to an acute obstruction not in the biliopancreatic limb (94% versus 27%; P<.001).

CONCLUSION

In RYGB patients, there is an association between small bowel obstruction and an elevated amylase or lipase. Acute obstruction of the biliopancreatic limb can be difficult to diagnose, and in these patients, the sensitivity of elevated amylase or lipase is very high. RYGB patients with abdominal pain should have their amylase and lipase measured. It is important to recognize that an elevation of these enzymes is not likely a result of acute pancreatitis.

Hyperamylasaemia in ruptured aortic aneurysm: incidence and prognostic implications

A study was carried out to determine the incidence of increased serum amylase activity in patients with ruptured aortic aneurysm during the 48 h after presentation and to assess its clinical significance. In a prospective series of 25 patients, hyperamylasaemia occurred in ten and was significantly associated with poor outcome (P = 0.005). In patients who died or had a major complication, serum amylase activity was significantly higher than in those who had an uncomplicated postoperative recovery (P < 0.05). There was a correlation between preoperative serum amylase activity and length of stay in the intensive care unit after operation (rs = 0.78 (95 per cent confidence interval 0.54-0.90), P < 0.002). Serum amylase activity may be useful as a prognostic indicator in patients with ruptured aortic aneurysm.

Problems in the diagnosis and management of acute pancreatitis

Despite the lack of precise knowledge as to its exact mechanism of causation, acute pancreatitis continues to engage the clinician's attention. The world medical literature is replete with publications on the subject and the numerous Australian studies attest to the continuing clinical interest (Hennessy, 1965; Bennett and Jepson, 1966; Kune, 1968; Barraclough and Coupland, 1972; Battersby and Chapuis, 1977 and Reid and Kune, 1978). The majority of these reviews concentrate on the supposed aetiology and clinical features of acute pancreatitis and cover well trodden ground. It is the purpose of this paper to review the problems in the diagnosis and management of acute pancreatitis in the light of present knowledge and to relate these to 494 patients with acute pancreatitis admitted to St Vincent's Hospital, Melbourne, during the period 1968 to 1979. The diagnosis of acute pancreatitis in these 494 cases was made at operation, autopsy or by the demonstration of an elevation in the serum amylase above 1200 International units (I.U.) per litre in patients with compatible symptoms and signs.

A nonpancreatic source of the proteolytic-enzyme amidase and bacteriology in experimental acute pancreatitis

In previous studies of human and experimental acute pancreatitis, three main assumptions have been made. First, that the disease is due to activation of pancreatic proteolytic enzymes in the pancreas with resulting "autodigestion" of the gland. Second, that interstitial pancreatitis is a mild form of hemorrhagic pancreatitis into which it may progress, and third, that bacteria play little part, if any, in the initiation of the disease. These assumptions are now questioned. In the present study in dogs, levels of proteolytic enzymes in blood, thoracicduct lymph and peritoneal fluid were measured using benzoylarginine amide. Raised levels of amidase were found in hemorrhagic, but not with interstitial, pancreatitis, and biochemical examination of amidase suggested it was not a pancreatic protease, but with its broad specificity and stability derived from bacteria. Addition of antibiotic to the blind duodenal loop in hemorrhagic pancreatitis reduced the level of blood amidase, but Trasylol given intravenously did not, nor did it inhibit amidase in vitro. In all animals, histological examination was made of the pancreas at time of death. On bacteriology, it is concluded that experimental interstitial pancreatitis results from damage to the pancreatic duct system without infection, and haemorrhagic pancreatitis mainly from reflux of bacteria into the pancreatic ducts from the duodenum. Only bacteria such as Escherichia coli and Clostridium welchii that produce proteolytic enzymes and cytotoxins appear to be able to cause haemorrhagic pancreatitis, and these bacteria may explain the release of vasoactive polypeptides and the vascular effects. In hemorrhagic pancreatitis such bacteria were found in the pancreas, but none in interstitial pancreatitis. Evidence is given to suggest that pancreatic proteolytic enzymes are unlikely to cause the cell necrosis which is a pathological feature of hemorrhagic pancreatitis, and that "autodigestion" is likewise unlikely to be a cause of this condition. An extrapancreatic source of proteolytic enzymes from bacteria is now suggested in haemorrhagic pancreatitis, and more attention to bacteriology in human acute pancreatitis is urgently needed. Amidase levels were highest in peritoneal fluid, suggesting a rationale for peritoneal lavage in the treatment of acute pancreatitis, and it is unlikely that Trasylol can give any benefit. The assessment of treatment of acute pancreatitis will be unsatisfactory as long as the proportion of haemorrhagic to interstitial pancreatitis in any series is not known accurately.

Postgastrectomy afferent loop obstruction due to efferent loop herniation simulating acute pancreatitis

A case of afferent loop obstruction due to efferent loop retro-anastomatic herniation following a Polya gastrectomy is presented. The clinical picture closely mimicked that of acute pancreatitis. The difficulty in diagnosis in this situation is discussed and the importance of operative techniques in its prevention emphasized.

Retroanastomotic hernias after gastrojejunal anastomoses

Images