Weil's syndrome with bone marrow involvement after collecting walnuts

A 65 year-old man was transferred to our department from a neighbouring hospital with anuria and epistaxis. A few days prior to hospitalization, he had experienced severe muscular and joint pain accompanied by chills. A careful history revealed that, in recent weeks, the patient had frequently collected wild walnuts growing, for the most part, on the banks of a small stream, known to have an infestation of rats. The physical examination revealed pronounced jaundice of the skin and sclerae, and petechia on the lower legs. Laboratory results showed marked thrombocytopenia, hyperbilirubinaemia, appreciably elevated urine retention parameters and increased C-reactive protein. During the subsequent course of his illness, serum leptospiral antibody titres were elevated, indicating an acute leptospiral infection manifesting as Weil's syndrome. Silver staining (>>Warthin-Starry