Rattus norvegicus (Norway rat) is the main reservoir host of pathogenic Leptospira, the causative agent of leptospirosis, in urban environments. Pathogenic Leptospira forms biofilms in the environment, possibly contributing for bacterial survival and maintenance. Nonetheless, biofilms have not yet been studied in natural animal reservoirs presenting leptospiral renal carriage. Here, we described biofilm formation by pathogenic Leptospira inside the renal tubules of R. norvegicus naturally infected and captured in an urban slum endemic for leptospirosis. From the 65 rats carrying Leptospira in their kidneys, 24 (37%) presented biofilms inside the renal tubules. The intensity of leptospiral colonization in the renal tubules (OR: 1.00; 95% CI 1.05-1.1) and the type of occlusion pattern of the colonized renal tubules (OR: 3.46; 95% CI 1.20-9.98) were independently associated with the presence of Leptospira biofilm. Our data showed that Leptospira interrogans produce biofilms during renal chronic colonization in rat reservoirs, suggesting a possible role for leptospiral biofilms in the pathogenesis of leptospirosis and bacterial carriage in host reservoirs.

中文翻译：

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钩端螺旋体在 Rattus norvegicus（挪威大鼠）天然水库中生物膜的形成。

Rattus norvegicus（挪威大鼠）是城市环境中致病性钩端螺旋体（钩端螺旋体病的病原体）的主要宿主。致病钩端螺旋体在环境中形成生物膜，可能有助于细菌的生存和维持。尽管如此，尚未在呈现钩端螺旋体肾携带的天然动物宿主中研究生物膜。在这里，我们描述了由在钩端螺旋体病流行的城市贫民窟中自然感染和捕获的褐家鼠肾小管内的致病钩端螺旋体形成的生物膜。在肾脏中携带钩端螺旋体的 65 只大鼠中，24 只（37%）在肾小管内出现生物膜。钩端螺旋体在肾小管中的定植强度 (OR: 1.00; 95% CI 1.05-1.1) 和定植肾小管的闭塞模式类型 (OR: 3.46; 95% CI 1.20-9. 98) 与钩端螺旋体生物膜的存在独立相关。我们的数据显示，钩端螺旋体在大鼠水库肾脏慢性定植期间产生生物膜，表明钩端螺旋体生物膜在钩端螺旋体病的发病机制和宿主水库中的细菌携带中可能发挥作用。