Figure 1. Kidney sections of R. norvegicus stained positively for immunohistochemistry (IH) anti-L. interrogans. In A , we observed a low CT count and the tubules presented with IH staining restricted to the membrane of epithelial renal cells. In B , massive colonization is shown, with a high CT count, and the tubules also presented a pattern of IH staining occluding the lumen. Magnification: 400x.