Endocrine Abstracts

Introduction: There are fewer than 20 reported cases involving congenital adrenal hyperplasia (CAH) and myelolipoma. This is a rare benign tumor, often located on the adrenal, consisting of mature adipose and hematopoietic tissues. Its origin is unclear; the most accepted theory is the occurrence of blood capillaries reticuloendothelial cells metaplasia, in response to infection, stress or necrosis. In a small number of cases ACTH hypersecretion coexists.

Case report: Woman 56 years, is referenced to endocrinology due to external genitalia virilization. She presented melanodermia, hirsutism, androgenic alopecia and ambiguous genitalia. Height=141.2 cm; weight=60 kg; BMI=30.2 kg/m². Previous diseases: meningitis at 8 years, primary amenorrhea, hypertension, dyslipidemia, osteoarthropathy and left adrenalectomy for myelolipoma (12.5 cm) in 2007. Laboratory results: FSH 66 mUI/ml (<34), LH 21 mUI/ml (<25), estradiol 52 pg/ml (<14), DHEAS 1.3 μg/ml (0.35–4.3), androstenedione 44 ng/ml (0.5–3.4), 11-desoxycortisol 20 ng/ml (<8), 17-OHP 196 ng/ml (0.2–1.6), total testosterone 4.0 ng/ml (<0.9), ACTH 490 pg/ml (9–52), cortisol 9.7 μg/ml (5–25), IGF1 127 ng/ml (81–225), prolactin 10 ng/ml (<20), TSH 1.3 μUI/ml (0.4–4), FT4 1.3 ng/dl (0.8–1.9), renin 6770 μU/ml (7–76), aldosterone 302 pg/ml (40–310). Tetracosactide test (60 min): 17-OHP 200 ng/ml; 11-desoxycortisol 23 ng/ml. Pelvic US: uterus and ovaries not shown; pituitary MR: ‘… intra-pituitary 5 mm nodular area… microadenoma can’t be excluded…‘; abdominal CT: ‘ left adrenal absence; right adrenal: 15 mm nodule… consistent with adenoma… hepatic steatosis… 2.1 cm cyst in left kidney‘. Karyotype: normal. Genetic analysis: ‘…homozygous for g.999 T>A severe mutation, associated with enzyme 21-hydroxylase activity reduced to 1–2% of normal…‘ Dexamethasone 0.5 mg/day was started.

Conclusions: This is a very challenging case in terms of diagnosis: a simple virilizing CAH in a patient with a large myelolipoma. This case reinforce the theory that the prolonged prolonged hypersecretion of ACTH can lead to myelolipomatous changes in adrenal gland due to chronic stress. The finding of ACTH receptors in myelolipoma will be necessary to prove it.