Salmonella Colitis as an Unusual Cause of Elevated Lipase

Abstract

Salmonella infections are a reported, albeit uncommon, cause of acute pancreatitis. However, Salmonella may precipitate elevated serum lipase levels without other signs or symptoms of acute pancreatitis. The following is a case of Salmonella colitis with elevated serum lipase but without clinical pancreatitis. A 50 year old male presented with a one week history of watery, bloody bowel movements, nausea and vomiting associated with fevers, chills, and abdominal pain. Imaging showed diffuse small bowel and colonic thickening consistent with infectious colitis and stool cultures were found be positive for Salmonella enterica. He was treated with a course of Ciprofloxacin. Shortly after discharge, the patient returned to the ED with nausea and vomiting unrelated to oral intake. Though he had minimal abdominal pain, a serum lipase was measured and found to be elevated to 1929 and amylase elevated to 230. The patient denied any history of drinking and an abdominal ultrasound showed no evidence of gallstone pathology. A CT Abdomen/Pelvis showed a normal pancreas without any signs of inflammation. His nausea and vomiting abated without intervention and he was able to tolerate a regular diet. While an elevated serum lipase may typically confirm the diagnosis of acute pancreatitis, elevated lipase levels may also be seen in other disorders. For instance, elevated serum lipase levels have been reported in patients with infectious colitis without clinical pancreatitis, though this is exceedingly rare. In addition, one study demonstrated that serum lipase may be elevated in Salmonella colitis, but may not have clinical significance. This most significant elevation in lipase was seen in Salmonella enterica serovar typhimurium. There are several hypotheses for the enzyme elevations, including increased intestinal inflammation with increased permeability leading to an increase in reabsorption of lipase. There is also some evidence that Salmonella species are present in the bile fluid and gallstone cultures and may directly infect the pancreas via the biliary duct. Regardless of the pathophysiology, physicians need to be aware that elevations in serum lipase and amylase may not always be clinically significant and should note these alternative causes, including Salmonella infections.