Morphologic and morphometric evaluation of pancreatic islets in chronic Chagas' disease

Abstract

Purpose: Hyperglycemia and abnormal glucose tolerance tests observed in some patients with chronic Chagas' disease suggest the possibility of morphological changes in pancreatic islets and/or denervation. The purpose of this study was to describe the morphology and morphometry of pancreatic islets in chronic Chagas' disease.Methods: Morphologic and computerized morphometric studies were performed in fragments of the head, body, and tail regions of the pancreas obtained at necropsies of 8 normal controls and 17 patients with chronic Chagas' disease: 8 with the digestive form (Megas) and 9 with the congestive heart failure form.Results: The Megas group had a larger (p < 0.05) pancreatic islet area in the tail of the pancreas (10649.3 ± 4408.8 µm 2 ) than the normal control (9481.8 ± 3242.4 µm 2 ) and congestive heart failure (9475.1 ± 2104.9 µm 2 ) groups; likewise, the density of the pancreatic islets (PI) was greater (1.2 ± 0.7 vs. 0.9 ± 0.6 vs. 1.9 ± 1.0 PI/mm 2 , respectively). In the tail region of the pancreas of patients with the Megas form, there was a significant and positive correlation (r = +0.73) between the area and density of pancreatic islets. Discrete fibrosis and leukocytic infiltrates were found in pancreatic ganglia and pancreatic islets of the patients with Chagas' disease. Trypanosoma cruzi nests were not observed in the examined sections. Individuals with the Megas form of Chagas' disease showed increased area and density of pancreatic islets in the tail of the pancreas.Conclusion: The observed morphometric and morphologic alterations are consistent with functional changes in the pancreas, including glycemia and insulin disturbances.

Alterations in pancreatic β cell function and Trypanosoma cruzi infection: evidence from human and animal studies

“…By contrast, the studies that relied on the CL strain of the parasite or did not specifically identify the strain, could not find amastigotes within β-cells (Lenzi et al 1996; Saldanha et al 2001). These findings imply cell tropism among different T. cruzi strains, an experimental variable that not only deserves to be systematically analyzed in future animal studies but should be considered in the design of more specific tests that detect T cruzi strains in infected humans.…”

Inflammation and glandular duct dilatation of the tongue from patients with chronic Chagas disease

“…The perineuritis observed in the tongue of CD chronic phase patient has been described also in other organs such as the heart (Almeida et al 1988;Rocha et al 1996), colon (Corbett et al 2001), pancreas (Saldanha et al 2001), and esophagus (Adad et al 1991) from patients with CD chronic phase as well as in the heart from subjects with CD acute phase (Rocha et al 1996). In the present study, the subjects that had megaesophagus and megacolon also showed perineuritis in the nervous fibers of the tongue, thus indicating, perhaps, a neurotropism caused by the presence of the T. cruzi strain.…”

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

“…However, changes due to T. cruzi infection in other sites, such as gonads and kidneys (Cabrine-Santos et al 2003), central nervous system and endocrine glands (Saldanha et al 2001;Santos et al 2002), have not been objects of research to the same extent. Especially, in spite of accumulating evidence that the pancreas may be affected by Trypanosoma cruzi infection, this has not provoked similar interest.…”