Endotoxin and antiendotoxin antibodies in patients with acute pancreatitis.

OBJECTIVE: To elucidate the time course of endotoxaemia and antiendotoxin antibodies in patients with acute pancreatitis. DESIGN: Prospective clinical study. SETTING: University hospital, Germany. SUBJECTS: 25 patients with oedematous (n = 9) or necrotising (n = 16) pancreatitis, and 20 healthy controls. MAIN OUTCOME MEASURES: Concentrations of endotoxin and immunoglobulins (classes G, M, and A) directed at two lipid A molecules, four lipopolysaccharides, and alpha-haemolysin of Staphylococcus aureus measurements in plasma during a 12 day period. RESULTS: There were no differences in the degree of endotoxaemia between patients with oedematous and necrotising pancreatitis on admission. However, from the day after admission and throughout the observation period patients with necrotising pancreatitis had significantly higher concentrations of endotoxin than those with oedematous pancreatitis. Concentrations of IgM specific for endotoxin peaked at day 4, and then decreased in patients with oedematous pancreatitis while remaining high for those with necrotising pancreatitis. There was only a slight increase in IgA specific for endotoxin, and IgG and immunoglobulins to gamma-haemolysin remained steady throughout the observation period. There was strong cross-reactivity (r > 0.7) between IgM specific for endotoxin (70%), but this was less with IgA (52%), and IgG (20%). CONCLUSIONS: Necrotising pancreatitis is accompanied by persistent endotoxaemia with an extended rise in antiendotoxin antibodies. Patients with oedematous pancreatitis have a transient endotoxaemia with a temporary increase of Ig specific for endotoxin. Endotoxin stimulates the synthesis of specific antibodies (IgM) despite general immunosuppression.