Endocrine Abstracts

A 35-year-old lady presented in Feb 2022 for lower limb weakness for 2 months, easy fall and amenorrhoea for 6 months. Her potassium was 2.4mmol/l. Clinically, she had moon face and proximal muscle weakness. Her workup showed metabolic alkalosis, renal loss of potassium and high 24-hour urine free cortisol (UFC) 825 nmol/l (24-140), which was 5.9x above the upper limit of normal (ULN). The paired baseline ACTH and morning cortisol were 22.1 and 469nmol/l respectively. 1mg ONDST was 580nmol/l. 8mg DST was suppressible. CRH and DDAVP stimulation test respectively confirmed Cushing’s disease. MRI pituitary showed 3mm hypoenhancing lesion on the right of the pituitary gland. IPSS was done in 10/2022 with successful cannulation and confirmed Cushing’s disease (CD). Serial monthly 24-hour UFC showed cortisol was 21, 208, 612nmol/l. Cyclical CD was suspected. The patient resumed spontaneous monthly menses and got pregnant due to misunderstanding. At 9^th gestational week (GW), 24-hour UFC was 8.7x above ULN with muscle weakness. As she was having active CD, TSS at second trimester was advised. Before surgery, cabergoline and enoxaparin were given. 24-hour UFC reduces to 6.5x ULN on cabergoline 1.5mg 2x/week. TSS was done at 17 GW. Specimen was stained positive for prolactin, GH and ACTH. Cabergoline and potassium was stopped post-operatively. Stress dose of hydrocortisone was given then tapered to replacement dose. After TSS, the 24-hour UFC was at 2x ULN. The patient sustained left distal fibula fracture after stepping on uneven ground at GW 33+weeks. She had preterm premature rupture of membrane the next day. A healthy baby was delivered weighing 1.97 kg and was observed in the neonatal ICU. It was finally discharged home at 23 days old, weighing 2.51 kg. The patient was on hydrocortisone replacement. She is planned to reassess for any cortisol excess after 3 months. Up to 2021, 62 cases of CD complicated pregnancy are reported. The risk of maternal complication such as pre-eclampsia, gestational hypertension, gestational diabetes and risk of fetal complication including preterm birth, low birth weight, intrauterine death are higher in active CD. Therefore, TSS at the second trimester was advised in this patient. Secondly, it is difficult to assess for any remission after surgery. As the cortisol level is higher in normal pregnancy up to 2-3x ULN, the usual reference for CD remission cannot be applied. Thirdly, as this patient had cyclical CD, the periodically near normal cortisol level may not indicate a remission.