MON-472 Muscle Pain in a Female Patient with Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency: Resolution with Testosterone Therapy - A Case Report

Abstract Disclosure: J. Hubska: None. M. Bobrowicz: None. U. Ambroziak: None. Case report: A 32-year-old female (46XX) with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21OHD), salt-wasting classical form, was admitted for evaluation of severe muscle pain, muscle weekness, and depression. Diagnosed in the neonatal period, she had been treated with glucocorticoids (GCS) and mineralocorticoids since that time. Her current regimen included prednisolone 10mg/day and fludrocortisone 100 µg/day. For chronic insomnia, she had taken zolpidem 7.5 mg/day for several years. Muscle pain led to regular use of metamizole and paracetamol, with increased intake and reported dependency over the last three years. Physical examination revealed signs of glucocorticoid (GC) excess; weight gain, plethora, and easy bruising. There were no signs of hyperandrogenism, and menstruation remained regular. Three years earlier, reducing prednisolone to 7.5 mg/day worsened her condition, necessitating a return to 10 mg/day. Current biochemical studies showed complete suppression of ACTH (<1 pg/ml; N: 10-50), DHEAS (1.7 µg/dl; N: 98-340), and testosterone (<0.09 nmol/l; N: 0.29-1.67). Similar results were recorded three years earlier. CK, LDH, ALT, and AST levels were normal. Electromyography, electroneurography, a lactate curve test, brain MRI, and metabolic and rheumatologic diagnostics revealed no abnormalities. Due to anxiety and poor tolerance of lower prednisolone doses, attempts to reduce the dose were avoided. Symptoms were attributed to GC excess, androgen deficiency, and somatization. With complete androgen suppression and GC reduction impractical, testosterone prolongatum 50 mg i.m. every 4-8 weeks was initiated. Three months later, the patient reported significant improvement in overall well-being, including the resolution of muscle pain. Examination revealed arm muscle growth with no other signs of virilization. Menstruation remained regular. Testosterone and prednisolone were continued. Discussion: This case describes an unusual presentation of muscle pain and weakness in a 46XX patient with CAH due to 21OHD, likely resulting from complete androgen suppression caused by excessive glucocorticoid dosing during infancy. While essential for CAH management, excessive GC use can lead to complications like Cushingoid features and androgen suppression. Androgens are crucial for muscle mass and physical function, even in females, and their prolonged deficiency contributed to the patient’s symptoms, which resolved with testosterone therapy. Although rarely used in female CAH patients due to concerns about virilization, this case highlights the safe and effective use of testosterone to treat androgen deficiency. It underscores the importance of individualized treatment and further research on androgen replacement to improve outcomes and quality of life in CAH. Presentation: Monday, July 14, 2025