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

ABSTRACT

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.