Adrenoleukodystrophy in the Differential Diagnosis of Boys Presenting with Primary Adrenal Insufficiency without Adrenal Antibodies

Özet

Adrenoleukodystrophy (ALD) is an X-linked, metabolic disorder caused by deficiency of peroxisomal ALD protein resulting in accumulationof very-long chain fatty acids (VLCFA), primarily in the adrenal cortex and central nervous system. Approximately 35-40% of boys withALD develop cerebral ALD (CALD), which causes rapidly progressive cerebral demyelination, loss of neurologic function, and death.Approximately 70-80% of boys with ALD have impaired adrenal function prior to the onset of neurologic symptoms. We present aboy who had recurrent episodes of hypoglycaemia from age two years and was diagnosed with adrenal insufficiency without adrenalantibodies at age 5.5 years. Following initial normal VLCFA levels, subsequent VLCFA analysis demonstrated elevated C26 fatty acidsconsistent with peroxisomal dysfunction and suggestive of ALD, which was confirmed via molecular genetic analysis of the ABCD1gene. Brain imaging at age 7 suggested cerebral involvement and the child underwent successful allogeneic hematopoietic stem celltransplantation. At last assessment (11.5 years old), he was performing as expected for age. This case highlights the importance ofpursuing a diagnosis when clinical suspicion remains, and the significance of VLCFA analysis for patients with adrenal insufficiencywithout adrenal antibodies in securing an ALD diagnosis. Subsequent brain imaging surveillance can detect early, pre-symptomaticcerebral disease, allowing for timely treatment and successful arrest of cerebral disease progression.