Objective: Progressive familial intrahepatic cholestasis type 1 (PFIC1) is a rare, autosomal, recessive, inherited disease resulting from mutations in the ATP8B1 gene which is expressed at high levels in the small intestine and pancreas and at lower levels in the liver. Given this expression pattern, patients might be expected to have a pancreatic phenotype. Although pancreatitis and steatorrhea have been reported in patients with PFIC1, the available data on pancreatic function are not fully convincing. Therefore, the objective of this study was to assess exocrine pancreatic function in patients with PFIC1.
Material and methods: Three subjects with a diagnosis of PFIC1 were included in the study. The diagnosis was confirmed by molecular analysis of ATP8B1. Prior to surgical treatment (biliary diversion), two patients had steatorrhea and in the third patient, a borderline value for fecal fat excretion was documented. In one patient, liver transplantation also was subsequently performed. Exocrine pancreatic secretion was assessed by the use of fecal elastase-1 and chymotrypsin tests. Fecal lipase concentrations were determined in order to exclude isolated lipase deficiency. Other typical diagnostic procedures were performed annually.
Results: The results of the fecal tests were within the normal range. None of the three patients experienced any episodes that could be related to acute or chronic pancreatitis. Laboratory tests including serum amylase and lipase tests were always normal. Abdominal ultrasonography findings did not show any pancreatic pathology.
Conclusions: Pancreatic secretion in the study patients with progressive familial intrahepatic cholestasis type 1 was normal. The observed steatorrhea was not related to pancreatic insufficiency.