Pancreatic pseudocyst.

Pseudocyst formation is a well-known complication of pancreatitis. Pseudocysts of the pancreas are localized collections of fluid occurring within the pancreatic mass or the peripancreatic spaces often following acute pancreatitis or in a patient with chronic pancreatitis without any previous history of an acute episode. The pathogenesis depends on the etiology: in acute pancreatitis, enzyme-rich fluid and products of autodegradation accumulate; in chronic pancreatitis, the cyst results from an obstructed duct. The natural history of the diseases has become clearer with the advent of ultrasound and computed tomographic scanning. The incidence of pseudocysts is noted to be higher as a result of better diagnostic techniques. Pseudocysts must be suspected in patients who have persistent abdominal pain or consistently elevated levels of pancreatic enzymes. Nearly one third of pancreatic pseudocysts resolve spontaneously. Some, however, require intervention. Surgery was the only option available for many years. Recently, newer methods, such as percutaneous drainage and endoscopic cystenterostomy, have been used. Percutaneous drainage is inexpensive, has a low complication rate, and is done under local anesthesia. The recurrence rate is high with a one-time needle aspiration; this rate can be reduced to less than 10% by using an indwelling catheter. On the basis of a review of literature and our own experience, we believe that percutaneous continuous catheter drainage should be the first choice in the management of pseudocysts that require intervention. Experience with the endoscopic technique is increasing, and it may prove to be a viable alternative in skilled hands in the future.

Diagnostic tests for acute pancreatitis.

Serum amylase continues to be the most widely used test to diagnose acute pancreatitis; however, its popularity does not appear to be justified. The serum amylase test has a poor sensitivity and specificity. Furthermore, it has an extremely low sensitivity in detecting acute alcoholic pancreatitis, which is the most common cause of acute pancreatitis in city hospitals. Older assay techniques for serum lipase were cumbersome and time-consuming. The newer methods seem to have overcome the disadvantages of the previous techniques. They are quick, reliable, and inexpensive. Recent studies indicate that serum lipase may be a better test to diagnose acute pancreatitis. Therefore, serum lipase should be used more frequently in the diagnosis of acute pancreatitis. Serum trypsin, although sensitive, is difficult to estimate and is not routinely available. Serum elastase offers no additional benefit over the serum amylase or lipase tests. Markers such as alpha 2-macroglobulin, RNase, phospholipase, and polymorphonuclear elastase predict severity of disease, but assay techniques for these agents are still experimental and confined to specialized centers. C-reactive protein is a reasonably reliable indicator of severity and, because it is universally available, should be used more frequently. Of the imaging techniques, computerized tomography scanning is the best method to delineate the pancreas; however, ultrasound is more cost-effective in clinical practice.

Serum lipase levels in nonpancreatic abdominal pain versus acute pancreatitis.

OBJECTIVE: 1) To determine whether serum lipase is elevated in patients with nonpancreatic abdominal pain, and 2) to compare the levels of serum lipase and serum amylase found in patients with nonpancreatic abdominal pain with those found in acute pancreatitis in order to differentiate between the two groups. METHODS: Serum lipase and amylase levels were estimated in 95 patients with nonpancreatic abdominal pain (group A). These levels were then compared with those found in 75 patients with acute pancreatitis (group P). RESULTS: Serum amylase in group A ranged from 11 to 416 U/L [mean 58 +/- 46 (SD)]. Three patients (3.3%) had raised amylase levels. The maximum elevation noted in this group was 416 U/L. Serum amylase in group P ranged from 124 to 13,000 U/L (mean 1620 +/- 1976). Twenty of the 75 patients (27%) in group P had levels that overlapped those found in group A. The serum lipase in group A ranged from 3 to 680 U/L (mean 111 +/- 101). Ten of the 93 patients (11%) had elevated lipase levels. The maximum elevation noted was roughly 3 times normal (680 U/L). Serum lipase in group P ranged from 711 to 31,153 (mean 6705 +/- 7022). None of the patients in group P had levels that overlapped those found in group A. The sensitivity of a serum lipase level > 3 normal in detecting acute pancreatitis was 100% and the specificity was 99%. The corresponding figures for serum amylase were 72% and 99%, respectively. CONCLUSION: A serum lipase level > 3 normal has a better diagnostic accuracy than serum amylase in differentiating nonpancreatic abdominal pain from acute pancreatitis.

Ingestion of corrosive substances by adults.

Compared with the ingestion of corrosive substances in children, this problem tends to be more serious, in adults, because its intent is often suicidal, rather than accidental. The severity and extent of damage produced to the gastrointestinal tract depends on the morphological form of the caustic agent. In the acute stage, perforation and necrosis may occur. Long-term complications include esophageal stricture, antral stenosis, and the development of esophageal carcinoma. X-rays of the abdomen and chest should be done initially to detect any evidence of perforation. Endoscopy should be performed as soon as possible in all cases to evaluate the extent and severity of damage, unless there is evidence of perforation. A complete examination is feasible in most cases. Stricture formation is more common in patients with second- and third-degree burns. Measures to prevent stricture formation, including the use of steroids, have not been successful. Esophageal carcinoma usually occurs 40 yr after the time of injury.