IMPE Abstracts

Introduction: Adrenoleukodystrophy (ALD) is an X linked disorder caused by mutations in the ABCD1 gene which determine a peroxisomal defect that increases plasmatic levels of Very Long Chain Fatty Acids (VLCFA). This disease has an incidence of 1/20.000 births, with onset between 4 and 12 years old. It causes an irreversible loss of myelin in the brain and cerebellum and a progressive dysfunction of the adrenal gland that leads to adrenal insufficiency. Clinical presentation, neuroimaging and plasmatic dosification of VLCFA are critical for diagnosis. There is currently no curing treatment and it has a very poor vital and functional prognosis.

Case Report: 8 years and 5 months old male with no relevant family, perinatal or personal history. Normal neurodevelopment and growth. In 6 months he presented a neurocognitive regression given by poor social interaction, impaired vision and hearing, ataxia and a language disorder. He showed no symptoms of hypocortisolism. A brain magnetic resonance evidenced white matter alterations compatible with ALD. Basal cortisol levels were in the gray zone (13.7 mg/dL) and adrenocorticotropin levels were high (1556 pg/mL). He received substitution treatment with hydrocortisone (10 mg/m2/day) and palliative care regarding the neurological déficit. The diagnosis was confirmed by high VLCFA plasmatic levels. No molecular genetic analysis of the ABCD1 gene took place.

Discussion: VLCFA restricted diets have no efficiency due to the persistent endogenous synthesis of VLCFA. Bone marrow transplants have proven to delay the illness progression in those patients with mild neurological symptoms. In those without neurological compromise, Lorenzo’s oil inhibits the enzyme responsible for fatty acid elongation and may slow down deterioration. Palliative care is the only option in patients with severe neurological affectation. The adrenal insufficiency is treated with subtitutive doses of glucocorticoids.

Conclusion: Though infrequent, ALD is an inborn error of metabolism with poor prognosis and lack of curative treatment that can justify its inclusion in the newborn screening program. Family study may help diagnose presymptomatic hemizygous boys in order to initiate early treatment.