Endocrine Abstracts

A 32-year-old man was referred for investigation of spastic paraparesis. There was a history of two seizures in the past. Of note was that his mother had previously been investigated for a mild spastic paraparesis, and had been diagnosed with idiopathic generalised epilepsy. MRI scan of the cervical and thoracic cord appeared normal but the MRI brain scan showed diffuse high signal intensity areas in the occipital white matter of both cerebral hemispheres. An EEG suggested idiopathic generalized epilepsy. Because of the MRI appearances, a diagnosis of multiple sclerosis was considered and a lumbar puncture was performed. He started vomiting and complained of a severe headache after the lumbar puncture and became hypotensive. His serum sodium was initially normal but fell to 105 mmol/l. His serum potassium was 3.3 mmol/l with normal urea and creatinine. An endocrine opinion was sought. He was noted to be pigmented. Addison’s disease was suspected and he was started on hydrocortisone and fludrocortisone. Serum cortisol came back at 125 nmol/l and ACTH 1250 ng/l. In the light of his adrenal failure, pyramidal tract signs, and MRI evidence of cerebral leukodystrophy, a diagnosis of X-linked adrenoleukodystrophy (ALD) presenting as adrenomyeloneuropathy was considered. This was subsequently confirmed biochemically by assay of very long chain fatty acids. His mother has been confirmed to be a carrier of ALD. His epileptic seizures are unrelated to his ALD. He was also found to be biochemically hypothyroid with a free T4 of 11 pmol/l and TSH of 45 min/l. His thyroid peroxidase antibody came back at 505 IU/ml. serum vitamin B12 level was normal. His adrenal, parietal cell and intrinsic factor antibodies are negative. Is his Addison’s disease auto-immune or related to his adrenomyeloneuropathy?