Convit J, Ulrich M, Pérez M, Hung J, Castillo J, Rojas H, Viquez A, Araya L N, Lima H De
Instituto de Biomedicina, Universidad Central de Venezuela/Ministerio de Salud y Desarrollo Social, Apartado 4043, Caracas 1010A, Venezuela.
Trans R Soc Trop Med Hyg. 2005 Jan;99(1):13-7. doi: 10.1016/j.trstmh.2004.02.005.
Biopsies of 71 cases of atypical cutaneous leishmaniasis from Costa Rican patients were evaluated by histopathological procedures and attempts were made to culture Leishmania from nine biopsies. Leishmanin skin tests were carried out in 31 patients and 112 healthy individuals. Additional biopsies from 19 patients from Nicaragua were evaluated by routine histopathology. Ten biopsies were studied by confocal and nine by scanning electron microscopy. Inorganic material was analysed using an electron probe for microanalysis. Leishmania parasites were isolated from only two biopsies, but 90.3% of the patients from Costa Rica were leishmanin-positive, as were 27.7% of healthy individuals. Routine histopathological studies revealed naked granulomas formed by differentiated macrophages. Abundant inorganic material was observed in sections examined by confocal microscopy. Electron probe analysis revealed that silica and aluminium were the predominant elements in large particles. We postulate that the presence of this inorganic material, possibly of volcanic origin, in the skin may modulate the immunological response to Leishmania and may inhibit visceralization in the cases caused by Leishmania chagasi.
对71例来自哥斯达黎加患者的非典型皮肤利什曼病活检样本进行了组织病理学评估，并尝试从9份活检样本中培养利什曼原虫。对31例患者和112名健康个体进行了利什曼原虫皮肤试验。对来自尼加拉瓜的19例患者的额外活检样本进行了常规组织病理学评估。10份活检样本采用共聚焦显微镜研究，9份采用扫描电子显微镜研究。使用电子探针进行微分析来分析无机材料。仅从两份活检样本中分离出利什曼原虫，但哥斯达黎加90.3%的患者利什曼原虫检测呈阳性，健康个体中这一比例为27.7%。常规组织病理学研究显示由分化的巨噬细胞形成的裸肉芽肿。在共聚焦显微镜检查的切片中观察到大量无机材料。电子探针分析表明，硅和铝是大颗粒中的主要元素。我们推测，皮肤中这种可能源自火山的无机材料的存在可能会调节对利什曼原虫的免疫反应，并可能抑制恰加斯利什曼原虫引起的病例中的内脏化。
