A 46–year–old man presented with three days of fever and nonspecific flu–like symptoms. He denied any prior medical history, or additional associated complaints. He noted an upper respiratory infection two weeks earlier, but that this had since resolved. His temperature was 39.3°C, heart rate was 137 bt/min, blood pressure was 106/69 mmHg, and respiratory rate was 36 bt/min. There was scleral icterus and diffuse jaundice. His cardiac, pulmonary and abdominal examinations were all normal. The sodium was 128 mmol/L, the BUN was 100, and the creatinine was 7. His direct bilirubin was 4; the AST and ALT were 464 and 223. WBC was 14,000 cells/mm3, the hemoglobin was 9 g/dL, and the platelets were 23,000 cells/mm3. LDH was 456; the CK was >8,000. On the second hospital day, he became hypotensive, requiring a dopamine infusion. Laboratory abnormalities were consistent with acute tubular necrosis, shock liver, anemia, and rhabdomyolysis. Although initial blood cultures were negative, vancomycin and pipericillin/tazobactam were empirically started. He required aggressive hydration and subsequent dialysis. His creatinine improved with dialysis, and his liver enzymes and CK trended down with supportive care. Among the many diagnoses considered, leptospirosis was initially dismissed due to lack of travel or animal exposure. Days after the patient’s issues had largely resolved and he had been discharged home, leptospiral antibodies were found to be positive.
A flu–like combination of symptoms is a common presentation in the hospitalist setting. While this constellation of symptoms can point to a myriad of diseases, the acute severity of illness is critical. Severe leptospirosis, also known as Weil’s disease, presents acutely with a multitude of clinical findings, including fever, jaundice, acute kidney injury, refractory shock, and hemorrhage. History of exposure to animals is generally the predominant factor for clinical suspicion since transmission to humans is through contact with contaminated urine from rats, dogs, cattle and pigs. However, as in this case, elevated BUN and creatinine with mixed hyperbilirubinemia and aminotransferases may suggest severe leptospirosis. Serologic assays are diagnostic, but efficient confirmatory testing is lacking. Cultures do not become positive for weeks and the gold standard, microscopic agglutination test (MAT), is only done at the CDC. The spirochete itself is additionally difficult to isolate, requiring specific media, and found in blood during the first 3–10 days of illness and urine in 2–4 weeks. Most cases resolve spontaneously in 7–10 days without permanent sequelae. Treatment is usually supportive and does not require antibiotics although they may shorten the duration of illness.
This case highlights that diseases should not be excluded from the differential if symptoms, exam, and lab findings fit. Patients are not always aware of exposures that increase clinical suspicion for certain illnesses.