Vascular and nerve lesions of the diabetic foot--a morphological study

The microcirculation in neuropathic diabetic feet is the subject of the same changes found in other end organs of the diabetic patients. In diabetic neuropathy, abnormal neurogenic regulation of the hemodynamics in the small vessels may contribute to the development of microangiopathy, which is manifested as increased basement thickening.

The study has been made on a group of 25 patients: nine with diabetes mellitus type 1 and 16 patients with diabetes mellitus type 2. All patients were affected by peripheral diabetic neuropathy and showed various degrees of lesions on the foot level. All cases required amputations done at the lower extremity of the limbs. Tissue fragments were processed for the standard histopathological exam, using Hemalaun-Eosin, trichromic Szekely and van Gieson staining.

The histopathological examination revealed on the skin level--ulcerations covering large areas, while entire sections showed hyperacanthosis. At the dermis level, the microscopic panel was dominated by the presence of the inflammatory infiltrate. The absence or the degeneration of the sweat glands, the presence of venous stasis and perivascular bleedings completed the morphological panel of the dermis. On the microcirculation level, the endothelial cells have a flat smooth inflated aspect. In the case of the large arterioles and arteries of muscular type, we observed the presence of the fibrous tissue on the level of media, calcium deposits on intima, mediocalcinosis.

The identification of vascular and nervous morphological structures in the complicated diabetic foot allows the extension of the knowledge related to the pathological background of this condition. The vascular lesions, which appeared on the microcirculation level, are consequently involving arterioles and arteries of muscular type and are being accompanied by nervous lesions shown through morphological changes of the peripheral nerves. The overall morphological contest of the complicated diabetic foot involves lesions of the epidermis, dermis, and muscles.