Clinical value of a new fecal elastase test for detection of chronic pancreatitis

Several pancreatic function tests exist, but their role in the diagnosis of chronic pancreatitis is controversial. Here we analyzed the clinical value of a newly available fecal elastase assay.

Fecal samples from 212 patients treated in our hospital from January to September 2002 were taken. Chronic pancreatitis was assumed when ductal alterations were present in ERCP. The severity of disease was assessed according to the Cambridge classification. Elastase (test from ScheBo, Germany) and chymotrypsin (Roche Diagnostics) were measured. As a new parameter an elastase ELISA from BIOSERV (Rostock, Germany) was employed. Specificity, sensitivity, and accuracy of each test as well as the ROC curves were calculated.

In 45 patients (21.2%) chronic pancreatitis was diagnosed. The sensitivities of elastase from ScheBo, elastase from BIOSERV and chymotrypsin were 68.9%, 77.8%, and 57.8%, respectively. The corresponding specificities were 77.2%, 76.0%, and 52.7%. When a cut-off for the elastase tests of 100 U/ml was used the sensitivities (57.8%) and the specificities (89.2%) for both elastase tests were similar. The areas under the ROC curves for the ScheBo elastase, BIOSERV elastase, and chymotrypsin were 0.805, 0.840, and 0.628, respectively. The higher AUC of the BIOSERV test was maintained when patients with mild-moderate chronic pancreatitis (Cambridge I-II) were analyzed separately.

The new elastase assay could probably replace the older test and was also much better than chymotrypsin.