An 82-year-old dialysis patient developed an infection caused by a rare black mold called Arthrocladium tropicale, which had never been documented in humans before. The infection came from poor environmental conditions including moisture and ant infestations near the patient’s dialysis supply storage area. Doctors identified the fungus using genetic testing and treated it successfully with antifungal medication combined with removal of the dialysis catheter. This case shows how important it is to keep dialysis equipment areas clean and dry to prevent rare infections.