Ultrastructural observations of intermediate cells in chronic pancreatitis

Background/Aims: The intermediate cells exhibiting both exo- and endocrine features occur in small numbers in the normal and pathologic pancreas of many animal species. In human pathology their presence has been reported in children with hyperinsulinemia, in hypoglycemia, and chronic hypergastrinemia Methodology: Fragments of the pancreas collected from 27 patients operated on for chronic pancreatitis of various intensity fibrosis (I-0 - IV0) was subjected to ultrastructural analysis. Results: All chronic pancreatitis cases revealed the presence of intermediate cells that were found outside Langerhans islets, separately or in small groups. They were more common in III0 and IV0 chronic pancreatitis. All forms of chronic pancreatitis with 10 - IV0 fibrosis showed, apart from undamaged cells, numerous intermediate cells with features of destruction. Some intermediate cells contained fibrillate cytoplasm inclusion bodies. Intermediate cells took part in the formation of acini and were also found among ductural cells. Conclusions: The presence of intermediate cells both within the acinar texture and among proliferating ductular cells confirms the common origin of these cellular elements of the pancreas. In chronic pancreatitis intermediate cells appear during pancreatic texture regeneration, being rather abnormal cell forms produced in this process than an intermediate stage in precursor cell differentiation.