100% N4-acetyl-sulfamethoxazole stone induced by Trimethoprim-Sulfamethoxazole in an HIV patient being treated for toxoplasmosis

Matthew S DeMasi; Ari P Bernstein; Michael Schulster; Mark V Silva

doi:10.1016/j.eucr.2020.101453

100% N⁴-acetyl-sulfamethoxazole stone induced by Trimethoprim-Sulfamethoxazole in an HIV patient being treated for toxoplasmosis

Urol Case Rep. 2020 Oct 17:34:101453. doi: 10.1016/j.eucr.2020.101453. eCollection 2021 Jan.

Authors

Matthew S DeMasi¹, Ari P Bernstein², Michael Schulster², Mark V Silva²

Affiliations

¹ Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, United States.
² Department of Urology, NYU Langone Medical Center, 222 East 41st Street New York, NY 10017, United States.

Abstract

Trimethoprim-Sulfamethoxazole is a common antibiotic used to treat urinary tract infections, as well as a prophylactic agent in HIV patients with low CD4 counts. Exceedingly rare are stones consisting purely of its metabolite, N⁴-acetyl-sulfamethoxazole, and management strategies are not well documented in the literature. We present a case of a patient with HIV who was found to have obstructing ureteral calculi composed of 100% N⁴-acetyl-sulfamethoxazole. Our report contributes a unique case of a Bactrim-induced stone in an immunocompromised patient. Similar patients can be prophylactically treated with diuresis and urinary alkalinization, as well as consideration for alternative medication use.

Keywords: Bactrim stone; HIV; Toxoplasmosis; Urolithiasis.

Publication types

Case Reports