Acute kidney injury induced by thrombotic microangiopathy in two cases of Bothrops envenomation

Bothrops snakes are the most frequent agents of snakebites in South and Central America. Acute kidney injury (AKI) is one of its complications and has multifactorial origin. Thrombotic microangiopathy (TMA)-induced AKI in snakebites is uncommon and is not described in Bothrops envenomation.

We report two cases of patients bitten by young Bothrops jararaca who developed AKI induced by TMA. Both patients evolved with mild envenomation and received the specific antivenom within 4 h after the snakebite. None of them had hypotension or shock, bleeding or secondary infection. Patient 1 (P1) was diabetic and using oral hypoglycemic drugs, and patient 2 (P2) was hypertensive without regular use of medication. On admission, both patients had levels of fibrinogen lower than 35 mg/dL, D-dimer higher than 10,000 ng/mL. They evolved with AKI, thrombocytopenia, normal coagulation assays, anemia, lactate dehydrogenase (LDH) elevation, low haptoglobin levels, negative direct antiglobulin test, and presence of schizocytes in peripheral blood. Only P1 required renal replacement therapy, and plasmapheresis was not required. Both patients were discharged and did not require outpatient dialysis, and subsequently had normal creatinine levels.

TMA may occur in Bothrops jararaca envenomation, even in mild cases that received early specific antivenom.