Case Presentation:

A 48‐year‐old woman presented with 2 episodes of bright red blood per rectum. Medical history included diverticular disease responsible for a previous episode of gastrointestinal bleed and congenital adrenal hyperplasia from 21‐hydroxylase deficiency. On exam, the patient had predominant masculine features, male pattern frontal baldness, and hemoglobin of 15.6. After being admitted, her gastrointestinal bleeding became hemodynamically significant, requiring transfusion of 5 units of packed red cells and transfer to the intensive care unit. Two tagged red blood cell scans and angiography of the mesenteric arteries with use of thrombolytics failed to delineate a bleeding site. On day 3, colonoscopy showed multiple diverticula through the entire colon. She continued to have bloody bowel movements and dropped her hemoglobin by 9 g over 3 days. CT scan of abdomen showed diverticulosis coli, a normal right adrenal gland, an unvisualized left adrenal gland, and large fat containing a more than 17‐cm left retroperitoneal mass with internal hemorrhage suggestive of an adrenal myelolipoma. Because of ongoing colonic bleeding and the adrenal mass, the patient was taken for surgery. She underwent subtotal colectomy and left adrenalectomy (2 fragments, 420 and 600 g), and no invasion was found between the adrenal mass and colon. Pathology confirmed diagnosis of giant adrenal myelolipoma and extensive colonic diverticula. She was discharged in good condition.

Discussion:

Adrenal myelolipomas, rare incidental benign tumors first described in 1905, are usually small and unilateral. They consist of mature adipose cells and hematopoietic myeloid cells. These tumors have a very slow but continued growth, and their volume and weight vary significantly from small lesions of a few grams to huge masses. Giant adrenal myelolipomas can weigh up to several kilograms; 70 cases have been reported in the literature previously. The pathogenesis of adrenal myelolipomas remains unclear. Some evidence indicates that ACTH may have a role in the development of these tumors, demonstrated by an increase in the relative frequency of myelolipomas in patients with excessive adrenocorticotropic hormone (ACTH) secretion, such as in congenital adrenal hyperplasia, Nelson's syndrome, and Addison's disease. To date, 25 cases have been reported of myelolipoma in association with congenital adrenal hyperplasia, with most cases reported in patients with 21‐hydroxylase deficiency. Although myelolipomas are usually asymptomatic, they can cause symptoms because of hemorrhage, compression, and obstruction. Radiographic evaluation gives pathognomonic findings on CT or MRI given the high fat content of the tumor. Surgery should be performed if symptoms occur, especially for large myelolipomas that are at high risk of spontaneous rupture with hemorrhage and life‐threatening shock.

Conclusions:

The purpose of this case report is to increase general awareness of this rare tumor and provide a recent literature review.

Disclosures:

T. Patel ‐ Lankenau Medical Center; S. Vootukuri ‐ Lankenau Medical Center; C. Kuntz ‐ Lankenau Medical Center.