Endocrine Abstracts

Background: Leptospirosis is an endemic zoonosis in the Philippines, with complications including jaundice from liver injury and acute kidney injury requiring renal replacement therapy. On the other hand, thyroid storm, most commonly in the setting of Graves’s disease, is a rare complication of hyperthyroidism. To date, thyroid storm has not been documented in patients with severe leptospirosis.

Case Presentation: Herein, we present the case of a 52-year-old man, with no known thyroid disease and with prior wading in flood waters, who presented with fever, conjunctival suffusion, icterisia, and oliguria. He arrived on the 7^th day of illness with hypotension and atrial fibrillation. Workups revealed low thyroid stimulating hormone (TSH), elevated free T4 (FT4), and elevated free T3 (FT3). There was also elevated serum creatinine, leukocytosis, and thrombocytopenia. He was diagnosed with severe leptospirosis, started on ceftriaxone intravenously, and underwent hemodialysis. He subsequently developed hemoptysis, prompting intubation and veno-venous extracorporeal membrane oxygenation (V-V ECMO). Thyroid storm was suspected when he had persistent fever in the background of hyperthyroidism and atrial fibrillation. After starting propylthiouracil, supersaturated potassium iodide, and intravenous hydrocortisone, there was lysis of fever and improvement in hemodynamic status. On the 3^rd day of V-V ECMO, significant improvement in oxygenation and resolution of pulmonary hemorrhage allowed weaning and decannulation. There was, however, eventual development of ventilator associated pneumonia and agranulocytosis, prompting the discontinuation of propylthiouracil. Despite the addition of broad-spectrum antibiotics, intractable metabolic acidosis and hypotension ensued, which led to the patient’s demise. TSH receptor antibody was eventually revealed to be undetectable, while thyroid ultrasound was unremarkable.

Discussion: Overlap of symptoms between thyroid storm and severe leptospirosis, such as fever and jaundice, may delay early diagnosis and management of thyroid storm. Furthermore, the full therapeutic regimen was not maximized due to hypotension and development of agranulocytosis. While there is documented success on the use of V-V ECMO in severe leptospirosis, the utility of ECMO in thyroid storm is limited to Veno-Arterial ECMO for thyrotoxicosis-induced cardiomyopathy. To date, there have been no published reports of leptospirosis occurring simultaneously with thyroid storm. The absence of thyroid nodules or a diffusely enlarged thyroid gland, together with an undetectable thyroid receptor antibody, should prompt consideration of destructive thyroiditis from severe leptospirosis.

Conclusion: The case highlights diagnostic and management challenges in a rare case of thyroid storm in the setting of severe leptospirosis. Keywords: ECMO, leptospirosis, thyroid storm, Weil’s