Reversibility of exocrine pancreatic failure in chronic pancreatitis.

In patients with chronic pancreatitis, the development of exocrine pancreatic failure is generally thought to be an irreversible process. We found evidence to the contrary in a prospective study of 70 patients who were evaluated by endoscopic retrograde cholangiopancreatography and sequential measurements of stool fat, percent urinary PABA excretion, and serum trypsin during a follow-up time period of 1-4 yr. Initial p-aminobenzoic acid (PABA) testing showed exocrine failure in 51 patients, 35 of whom had low serum trypsin levels while 14 (27%) disclosed unexpectedly high trypsin concentrations. Ductal morphology was similar in patients with low and high trypsin values. In 8 of the latter cases, steatorrhea improved and pancreatic function tests became normal after pancreaticojejunostomy in 4 patients, alcohol abstinence in 3 patients, and spontaneous resolution of a pseudocyst in 1 patient. Pancreatic cancer was present in a further 3 patients. Of the 37 patients with low PABA and low trypsin at the outset, there was no improvement of exocrine function in 17 of 18 who were surgically treated. Conservative treatment had a similar effect in another 6 patients who were available for follow-up in this group. The mean duration of symptomatic disease was shorter (p less than 0.001) in patients with low PABA and high trypsin levels (1.4 +/- 1.2 yr) than in those with low PABA and low trypsin levels (4.5 +/- 1.3 yr). The results show that up to 20% of patients with chronic pancreatitis have exocrine pancreatic failure, which is apparently due to early ductal obstruction of a gland with preserved function; this situation can be suspected when low urinary PABA excretion and high serum trypsin levels are simultaneously found; and (c) exocrine failure may be reversible in these patients by using a pancreatic drainage procedure or alcohol abstinence. Such a peculiar pattern of pancreatic function tests may also suggest pancreatic cancer.