Giant Expanding Rectus Sheath Hematoma after Inadvertent Intrarectus Erythropoietin Injection

The occurrence of large rectus sheath hematomas following erythropoietin injection is not commonly reported. In this case, the patient was known to have stage 5 chronic kidney disease (CKD) and hypertension and was on regular maintenance hemodialysis. She presented with a tender lump in the left iliac fossa, associated with a low hemoglobin level (5.4 g/dL). Further imaging revealed a large rectus sheath hematoma measuring 16 x 10 x 4.5 cm. The patient's history included an erythropoietin injection administered at the same site in the abdomen. Under hemodialysis support, digital subtraction angiography was performed, followed by angioembolization of the left inferior epigastric artery. The patient stabilized and was discharged after an uneventful recovery, with continued well-being at the 6-month follow-up. The hematoma was likely caused by an inadvertent intramuscular injection of erythropoietin, which may have injured the left inferior epigastric artery. The presence of CKD and hypertension likely contributed to the severity of the hematoma. While most rectus sheath hematomas are minor and self-limiting, large hematomas are rare and may require intervention.