Role of polymorphonuclear leukocyte in diabetic foot

To study the etiopathogenesis of foot injuries in patients of uncontrolled diabetes mellitus. Retrospective study of tissue samples received from diabetic patients clinically diagnosed as gangrene. This study was conducted in the Department of Ophthalmology, JPMC, Karachi from July 2009 to June 2011. 150 cases of uncontrolled diabetes mellitus with wounds of foot were included. 150 cases of known diabetics with peripheral neuropathy and history of loss of sensation were subjected to follow up of 2 years follow up was done on the cases. As a first step blood sugar was brought under control and broad spectrum antibiotic was given. Wound debriment was done in all cases. The specimens were subjected to H/E and Gram's staining. In H/E, liquifactive necrosis, polymorphonuclear leukocyte, mononuclear cell infiltrate, few lymphocyte plasma cells and fibroblasts were seen. New blood capillaries were few or absent. both gram positive and gram negative organisms were isolated. 79% were gram positive and 21% were gram negative. Hyperglycemia causes relative anoxia in the micro environment of the tissue due to damage of peripheral neurons. Lack of adequate circulation leads to ischemia, which is super added by infection of the subcutaneous tissue. The resultant effect is liquifactive necrosis and complete lysis of tissue. Removal of such putrefied tissue is mandatory to stop further damage to the tissue

Novel detection of parvovirus B19 DNA & IgM antibodies in patients with non-occlusive gangrene of stomach & bowel.

Background: Gangrene of stomach or intestines owing to non-occlusive bowel infarction (NOBI) is a rare event with unknown etiolology. Since B19 may cause vasculitis, arteritis, angiopathy and more importantly, localized microvascular thrombi formation hence patients with bowel gangrene were investigated for B19 infection. Methods: Twelve patients (8 male and 4 females; median age 40 yr) of ischemic unexplained gangrene of bowel underwent emergency laparotomy. Eight cases had NOBI while four had occlusive bowel infarction (OBI). Anti-B19 antibodies in sera by ELISA and Western-blot and B19 DNA by PCR in sera and resected tissues were analysed. Results: All patients underwent resection of gangrenous bowel; with exteriorization followed by restoration wherever appropriate. Histopathology showed loss of bowel mucosa and crypts with inflammatory cell infiltration besides fibrin thrombus in gastric vessels. Sera of all 8 patents of NOBI had B19 genome by nested-PCR (VP1 unique) and in 6 by PCR (VP1-VP2). In three patients resected bowel tissues also had B19 DNA besides anti-B19 IgM and IgG antibodies. NOBI patients were reticulocytopenic and anaemic while one had necrotizing vasculitis of skin a year ago. No IgM antibodies to agents causing vasculitis (HTLV-I, HIV-1+2, CMV, HSV1+2, mumps virus and Mycobacterium tuberculosis) nor any abnormality in coagulation profiles were detected. In four OBI cases’s sera and resected bowel tissues and in control bowel tissues (n=36) no anti-B19 IgM antibodies or B19 DNA were detected. Conclusion: Novel finding of active B19 infection in non-occlusive gangrene of the bowel may be causal rather than casual.