Endocrine Abstracts

Lipodystrophy represents a broad spectrum of disorders, subdivided depending on aetiology (congenital or acquired) or the extent of adipose tissue absence (generalised or partial). A lack of adipose tissue results in systemic insulin resistance and ectopic fat deposition, which predisposes patients to metabolic syndrome and associated conditions such as non-alcoholic fatty liver disease and diabetes mellitus. Additionally, severe hyperinsulinaemia can generate ovarian androgen production, resulting in an incorrect diagnosis of polycystic ovary syndrome (PCOS) due to a combination of ovulatory dysfunction, androgen excess and severe polycystic ovaries on ultrasound. Juvenile dermatomyositis is a rare autoimmune inflammatory myositis that is associated with lipodystrophy. We present a case of a severe insulin resistance disorder in the setting of juvenile dermatomyositis referred to endocrinology with PCOS features. 25-year-old female diagnosed with juvenile dermatomyositis in childhood, presenting with rashes, joint pains and muscle weakness, which developed into contractures. She had a background history of steroid-induced hyperglycaemia, hypertension and recurrent calcinosis with JJ stents inserted. She was diagnosed with PCOS at age 15 and had been referred to Endocrinology by Rheumatology colleagues due to worsening symptoms of anovulation for over a year and significant hirsuitism. On exam, she was a wheelchair user with severe acanthosis nigricans around her neck, axillae and antecubital fossae bilaterally. In addition, there was evidence of partial lipodystrophy affecting her arms and legs and relatively sparing her face and abdomen. Her initial investigations revealed profound insulin resistance with a HOMA insulin ratio of 41.5 based on a glucose of 5.4mmol/l, c peptide of 15.2 and insulin level of 174miu/l(>1,000 pmol/l). There was biochemical evidence of androgen excess with elevated testosterone of 4.6nmol/land androstenedione of 15nmol/l. At this juncture, she was commenced on Provera, which she had a partial response to and metformin and spironolactone. She underwent a gonadotropin-releasing hormone (GnRH) suppression test to confirm gonadotropin-driven ovarian hyperandrogenism and explore potentially as a therapeutic option with add back oestrogen. After administration of triptorelin 3 mg, androgens were completely suppressed, with significant clinical improvement in symptoms. She continues on maintenance GnRH therapy with add-back oestrogen and progesterone. This case highlights severe insulin resistance syndromes as a non-PCOS form of androgen excess and the clinical utility of GnRH analogues.