A practical approach to the diagnosis of autoimmune pancreatitis

Autoimmune pancreatitis is a disease characterized by specific pathological features, different from those of other forms of pancreatitis, that responds dramatically to steroid therapy. The pancreatic parenchyma may be diffusely or focally involved with the possibility of a low-density mass being present at imaging, mimicking pancreatic cancer. Clinically, the most relevant problems lie in the diagnosis of autoimmune pancreatitis and in distinguishing autoimmune pancreatitis from pancreatic cancer. Since in the presence of a pancreatic mass the probability of tumour is much higher than that of pancreatitis, the physician should be aware that in focal autoimmune pancreatitis the first step before using steroids is to exclude pancreatic adenocarcinoma. In this review, we briefly analyse the strategies to be followed for a correct diagnosis of autoimmune pancreatitis.

Exocrine and endocrine pancreatic function in 21 patients suffering from autoimmune pancreatitis before and after steroid treatment

BACKGROUND/AIM

Autoimmune pancreatitis (AIP) responds rapidly and dramatically to steroid therapy. The aim of this study was to evaluate pancreatic exocrine and endocrine function in patients suffering from AIP both before and after steroid therapy.

PATIENTS AND METHODS

Fecal elastase 1 and diabetes were evaluated before steroid therapy and within 1 month of its suspension in 21 patients (13 males and 8 females, mean age 43 +/- 16.5 years) diagnosed as having AIP between 2006 and 2008.

RESULTS

At clinical onset, fecal elastase 1 was 107 +/- 126 microg/g stool. Thirteen patients (62%) showed severe pancreatic insufficiency (<100 microg/g stool), 4 (19%) had mild insufficiency (100-200 microg/g stool), while 4 (19%) had normal pancreatic function (>200 microg/g stool). Before steroids, diabetes was diagnosed in 5 patients (24%), all of whom had very low levels of fecal elastase 1 (<19 microg/g stool). Following steroids, fecal elastase 1 increased in all patients (237 +/- 193 microg/g stool) and observed levels were significantly higher than those seen before steroids (p = 0.001).

CONCLUSIONS

Patients suffering from AIP display exocrine and/or endocrine pancreatic insufficiency at clinical onset. These insufficiencies improve after steroid therapy.