Oh Rats!! An Unusual Case of Jaundice Due to Leptospirosis

Abstract

Conjugated hyperbilirubinemia in the absence of hepatocellular injury requires investigation of unique pathologic entities. Leptospirosis is a rare zoonotic infection which can result in conjugated hyperbilirubinemia and acute kidney injury. Humans are infected via rodent-urine contaminated water or soil. Incidence of Leptospirosis in the United States is extremely rare with estimates of only 100 cases annually, a majority of which are reported in Hawaii and California. Other complications include thrombocytopenia, ARDS, pulmonary hemorrhage and myocarditis. A 43 year-old Caucasian man residing in Detroit, Michigan presented with abdominal pain for five days. Associated symptoms included subjective fevers, generalized weakness and jaundice. He reported living with five dogs in a rat-infested home. He denied any recent travel or sick contacts. Examination revealed a jaundiced, dishevelled man with scleral icterus and marked conjunctival erythema without exudate (Figure 1). Lab work revealed leukocytosis, pyuria and conjugated hyperbilirubinemia, but unremarkable transaminases. The patient deteriorated within the next 12 hours, requiring transfer to the intensive care unit, mechanical ventilation and vasopressor support. Chest radiography revealed bilateral patchy infiltrates suggestive of ARDS (Figure 2). Ultrasound and CT scan of the abdomen were unremarkable. Leptospirosis IgM antibody was negative. The conjugated bilirubin continued to rise to a plateau of 22.8mg/dL. Molecular testing with RT-PCR revealed Leptospira DNA. The patient was treated with ceftriaxone leading to resolution of acute kidney injury and hyperbilirubinemia (Figure 3). Although incidence of Leptospirosis is extremely rare in the Midwestern United States, it must be considered in cases of conjugated hyperbilirubinemia and renal dysfunction. Hyperbilirubinemia is postulated to result from endothelial damage to hepatic capillaries and hyperplasia of Kupffer cells causing intrahepatic cholestasis. Important clues may include conjunctival suffusion (Figure 1) or rodent-infested living conditions. A Jarisch-Haerxheimer reaction (fever, rigors and hypotension) may occur after initiation of antibiotics as seen in this case. Molecular testing (RT-PCR) is the test of choice as serologic testing can be unrevealing in the early stages of infection. High index of suspicion and initiation of antimicrobial therapy are essential in avoiding the complications of this devastating zoonotic disease.Figure: Conjunctival suffusion and scleral icterus involving both eyes.Figure: Chest radiography unremarkable on presentation (day 0), however, repeat imaging on day 2 shows extensive diffuse airspace disease. Given worsening following initiation of antibiotics, this is consistent with a Jarisch-Haerxheimer reaction in retrospect.Figure: Graphical representation of the hospital course correlated with white blood cell count and bilirubin levels.