March hemoglobinuria progressed to acute kidney injury after kendo practice: a case report.

March hemoglobinuria is a hemolytic disease that can occur after intense exercise, especially kendo. Considering its rarity due to the lack of critical symptoms, it is important to note that occult blood-positive findings may be indicative of march hemoglobinuria if the patient underwent strenuous exercise. Therefore, clinicians should be aware of this possibility to provide timely and appropriate treatment.