Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042384 (vasculitis)
 20,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To study further the pathogenesis of Lucio's phenomenon, we have made a comparative histological study of 11 patients with Lucio's phenomenon and 12 with ENL. Confirming the findings of others, Lucio's reaction could be distinguished from ENL by epidermal necrosis and by necrotizing vasculitis manifesting necrosis in the walls of superficial vessels and severe, focal endothelial proliferation of mid-dermal vessels. Furthermore, in Lucio's phenomenon large numbers of AFB were found in evidently normal and in swollen or proliferating endothelial cells. We hypothesize that patients with Lucio's phenomenon have an exceptionally deficient defense mechanism, allowing unrestricted proliferation of AFB in endothelial cells, facilitating contact between bacterial antigen and circulating antibody and leading to infarction; also, this nadir of resistance allows unimpeded dissemination of AFB, accounting for the clinical features of diffuse non-nodular leprosy. Thus, an explanation is offered for the restriction of Lucio's phenomenon to patients with diffuse non-nodular lepromatous leprosy.
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PMID:Lucio's phenomenon: a comparative histological study. 57 50

The histopathological features in type I (lepra) reaction comprised a loose and disorganised granuloma in the upper and mid-dermis, dermal edema and variable cellular contents, namely, epithelioid cells, lymphocytes, giant cells, and macrophages. While ENL reactions, were characterised by predominant involvement of subcutaneous vessels, vasculitis, and polymorphonuclear infiltration in and around the blood vessels.
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PMID:The histopathology of type I (lepra) and type II (ENL) reactions in leprosy. 380 96

Pathogenesis of leprous neuropathy was studied from the standpoint of vasculitis. In vasculitic syndrome, mononeuritis multiplex is the most specific peripheral nerve injury. It occurs most frequently in small vessel vasculitis. Among them, the incidence is highest in microscopic polyangitis (MPO), Churg-Strauss Syndrome (CSS), and Wegener's granulomatosis (WG). All of them are categorized as ANCA associated disease. Because the disease activity is parallel with ANCA titer and ANCA is related directory to the pathogenesis of necrotizing vasculitis as well as the occurrence of peripheral neuropathy. Other small vessel vasculitis, such as lupus or rheumatoid vasculitis which are believed to occur by immune complex mechanism, are accompanied seldom by peripheral neuropathy. In WG, there are granulomatous lesions in upper and lower respiratory tracts which are supposed to be induced by Th1 dominant CD4 T cell infiltration. In cases of leprosy, if peripheral neuropathy were related to small vessel vasculitis, there might be two different pathogenesis. One is granulomatous vasculitis like WG in tuberculoid type. The other is immune complex type necrotizing vasculitis like SLE in lepromatous type, especially ENL. The site of these events may be small vessel in epineurium. Further immunologic studies are needed to clarify detailed mechanisms of leprous neuropathy.
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PMID:[Leprous neuropathy--observation from the standpoint vasculitis]. 1048 46

Lepra reactions are acute episodes occurring during the disease process of leprosy and are of 2 types: type 1 or reversal reaction and type 2 reaction or erythema odosumleprosum (ENL). In the episodes of lepra reaction several parts are affected including face and extremities like oral cavity. In the present case report we reported a rare case of lepromatous leprosy with necrotic ENL involving scalp apart from the usual sites. A 58 year old married male presented to us with complaints of spontaneous onset, recurrent eruption of multiple reddish raised painful lesions. Biopsy from the infiltrated skin over the back showed atrophic epidermis, free Grenz zone, diffuse and periadnexal macrophage granulomas with predominant mononuclear infiltrate, appandageal atrophy, fibrosis around the neural structures and leukocytoclastic vasculitis. Fites stain showed strong positivity for M. leprae. His routine blood investigations showed anemia (Hb = 7.8 gm%), neutrophil leukocytosis (TLC = 17,600, DLC = P66L28M4E2) and raised ESR (80 mm in the first hour). These bullous and necrotic lesions in leprosy may be a manifestation of severe type II reactions in patients with very high bacillary load.
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PMID:Unusual Presentation of Necrotic Erythema Nodosum Leprosum on Scalp: A Case Report. 2659 47