An: 2011, Nr.3, Articol Nr. 5

Title: 

Authors: 

      HISTOCHEMICAL AND IMMUNOHISTOCHEMICAL ASPECTS IN THE NEUROPATHIC DIABETIC FOOT AND THEIR CONTRIBUTION TO THE PATHOGENY OF THE DIABETIC FOOT COMPLICATIONS (Abstract): Although the microangiopathy of the foot may not be accepted as the primary cause for ulceration, there are morphological and functional changes of microcirculation in diabetes. The aim of our study was to identifying those who are important for the pathogeny of the complicated diabetic foot. Material and Method: We studied 20 diabetic patients (type 1 diabetes = 9 patients, 4 males and 5 females, type 2 diabetes = 11 patients, 7 males and 4 females) with a duration of diabetes between 10 and 20 years. All patients had peripheral neuropathy and distal lesions of the foot (ulcerations, gangrenes) and they were surgically treated (amputations limited at the lower level of the foot). During the surgery there were taken bioptic fragments from areas with tissue that apparently had no macroscopic modifications. We used the CD34 antibody (marker for the vascular endothelium) and the PGP9.5 antibody (pan-axonal marker). We also used the PAS technique to show the basement membranes. Results: The basement membranes of microcirculation were thickened and PAS positive both in the deep dermis, as well as in the superficial dermis. Quantitative ratio between capillary and arterio-venous shunts was different in the dermal papilla; it was also a different degree of expansion of these structures lumens. Marker CD34 showed a decreased number of endoneural capillaries. PGP9.5 showed fragmentation and disruption of the peripheral nerves of dermis as well as the ones of muscular tissue. Conclusions: The morphological modifications shown in our study support the microangiopathic theory of neuropathy, without invalidating the metabolic one. We think that both metabolic (derived from chronic hyperglycaemia) and vascular factors occur in the development and progression of neuropathy, contributing to the nervous disorder, both through the deficient contribution in nutrients and affecting the clearance of the metabolic products. The opening of the arteriovenous shunts, element observed in the anatomo-pathological preparations studied, may support the theory of the functional microangiopathy existing in the neuropathic diabetic foot.

Key words: DIABETIC FOOT, MICROANGIOPATHY, NEUROPATHY, CD34, PGP 9.5