Rhabdomyolysis and acute pancreatitis

To establish the incidence of rhabdomyolysis in patients with acute pancreatitis and to determine the effectiveness of myoglobin in assessing the severity of the disease.

Sixty-one patients having acute pancreatitis (33 males, 28 females, mean age 66 years, range 16-97 years) were studied; diagnosis of acute pancreatitis was based on the typical abdominal pain associated with elevated concentrations of serum lipase and further confirmed by imaging techniques. Rhabdomyolysis was defined as a level of serum myoglobin which is two or more times greater than the upper normal test limit. All patients had normal renal function at the time of the study, none had clinical and/or electrocardiographic signs of acute myocardial infarction and none were drug addicts. Forty-five patients had mild acute pancreatitis and 16 had the severe form of the disease. Serum myoglobin was determined using a nephelometric technique.

Patients with mild pancreatitis had serum concentrations of myoglobin (median and range; 35.7, 24-713 microg/L) similar to those with severe pancreatitis (26.8, 24-710 microg/L). Twelve of the 61 patients with acute pancreatitis (20%) had serum myoglobin concentrations above the upper normal limit: eight of the 45 patients with mild pancreatitis (17.7%) and four of the 16 patients with severe pancreatitis (25.0%). Four of the 61 patients with acute pancreatitis (7%) had serum myoglobin levels more than twice the upper normal limit: two with mild disease and two with the severe form of pancreatitis.

Rhabdomyolysis may occur asymptomatically in patients with acute pancreatitis, especially in those with the severe form of the disease. Serum myoglobin determination is not useful in establishing the severity of acute pancreatitis.