Functional and histopathological study of the pancreas in hamsters (Mesocricetus auratus) infected and reinfected with Trypanosoma cruzi.

Histopathological and functional changes in the pancreas were studied in 94 hamsters infected and reinfected with Trypanosoma cruzi VIC strain and in 73 non-infected normal controls. Infection in each animal was verified by microhematocrit, hemoculture, specific peroxidase anti-peroxidase, polymerase chain reaction and seroagglutination. Blood glucose and insulin were determined. The number of islets per section and the number of islet cells marked with antibodies were counted. Insulitis, neuritis, fibrosis, atrophy and inflammatory infiltrates were evaluated. Experimental chagasic infection caused pancreatitis similar to human Chagas' disease, involving acini, islets and nerves, with atrophy and fibrosis, although without correlation to the number of reinfections. Erratic blood glucose levels and a tendency to hypoinsulinemia were observed in infected animals. During the acute phase, the number of somatostatin and pancreatic polipeptide producer islet cells was lower in infected hamsters, which was eventually related to changes in blood sugar levels and hypoinsulinemia. Our findings favor the hypothesis of the existence of an endocrine form of chronic chagasic infection.