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| Id: | 18130
| | Autor: | Boddingius, J
| | Título: | Ultrastructural changes in blood vessels of peripheral nerves in leprosy neuropathy
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| | Fonte: | s.l; s.n; September 26, 1977. 19 p. ilus, tab.
| | Resumo: | The ultrastructure of blood vessels in endoperi and epineurium was studied in peripheral cutaneous nerve biopsies of 16 borderline (BB), borderline-lepromatous (BL) or lepromatous (LL) leprosy patients some of whom were in reversal reaction. Comparable vessels in nerve biopsies of control cases and vessels in skin lesion biopsies of the leprosy patients were also studied. Vascular changes were found in nerves of all the leprosy patients. The changes were pronounced in endoneurial vessels and affected 1. endothelial continuity and surface structure, 2. basement membranes od endothelium and pericytes, and 3. the vessel lumen. In addition, intra-endothelial (IE) Mycobacterium leprae were a feature in some of the patients. Gaps occurring between endothelial cells and plasma insudation both noticed in vessels of fascicles with early to very early neuropathy suggested extensive leakage which, in all propability, causes early nerve fibre damage. Luminal and abluminal endothelial protusions, which were frequently observed, may enhance transendothelial transposrt. Fenestrations and endothelial attenuation, possibly, lead to an increase in vascular permeability. Endothelial phagocytotic activity, particularly in small (epineural) arteries, appeared to be stimulated, possibly, by circulating M. Leprae. Basement membrane multilayering (a hyaline zone) was found peripherally to pericytes, as is the case in tuberculoid leprosy (Boddingus, 1976). In a number of patients, multilayering occurred also periendothelially. Perivascular zones, which are thought to initiate or aggravate neuropathological changes by impairment of diffusion of oxygen and nutrients or metabolites, were very wide in endoneurial vessels of patients in reversal reaction and this suggested an immunological aetiology. Partial or total vessel lumen occlusion, seen in advanced lepromatous neuropathy, most likely contributes to final nerve fibre degeneration and endoneurial fibrosis. M. leprae were found intra-endothelially in endoneurial vessels, though only fascicles with advanced neuropathy whereas bacilli were not seen in vessel lumina. By contrast, infascicles with realtively early neuropathy, solid (viable) bacilli were frequently encountered intra-axonally in myelinated fibres. This suggested thast, inmany instances, primary infiltration of M. leprae into nerve facicles may arise from intraaxonal..(AU).
| | Descritores: | PERMEABILIDADE CAPILAR
HANSENIASE/patol
DEGENERACAO NEURAL
NERVOS PERIFERICOS/patol
DOENCAS DO SISTEMA NERVOSO PERIFERICO/patol
FAGOCITOSE
VASA NERVORUM/patol
PELE/inerv
| | Limites: | HUMANO
MASCULINO
FEMININO
CRIANÇA
ADULTO
MEIA-IDADE
ADOLESCENTE
| | Meio Eletrônico: | - .
| | Localização: | BR191.1; 00031/s |
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