A Case of Babesiosis with Hematuria: Recognizing Atypical Presentations in Endemic Areas

Authors

• SARA M. KOLINSKI, University of LynchburgFollow

Specialty

Emergency Medicine

Advisor

Dr. Elijah Salzer

Abstract

This case report describes a 68-year-old male who presented to an emergency department in Massachusetts with a chief complaint of fevers and bloody urine. He was ultimately diagnosed with babesiosis, representing a rarely documented presentation of the tick-borne illness: true hematuria. Babesiosis is caused by the parasitic protozoa of the Babesia species, with Babesia microti being the most common. Because the parasite infects red blood cells (RBCs) and destroys them upon reproduction, hemoglobinuria secondary to intravascular hemolysis is a recognized complication. Hematuria, however, has not previously been identified as a sequela. The patient’s initial labs showed inclusions present in RBCs, which prompted reflex testing for malaria and tick-borne illnesses. The remainder of labs showed thrombocytopenia and creatinine of 1.2 mg/dL with unknown baseline. UA showed 3+ blood and 11-20 RBCs on urine sediment. Serology later confirmed that the patient had both babesiosis and Lyme disease. The patient remained stable, and on hospital day five he was discharged with continued antibiotics. The true hematuria, demonstrated by the presence of intact RBCs in the urine, identifies a unique presentation of babesiosis. Although the exact pathophysiology of the hematuria remains unclear, this case proposes that it may have been due to acute kidney injury (AKI) in the setting of hemolysis suggested by a creatinine that was suspected to be mildly elevated from baseline. It highlights the value of thorough evaluation, maintaining a broad differential, and avoiding premature diagnostic closure.

Recommended Citation

KOLINSKI SM. A Case of Babesiosis with Hematuria: Recognizing Atypical Presentations in Endemic Areas. University of Lynchburg DMSc Doctoral Project Assignment Repository. 2026; 8(1).