X-linked adrenoleukodystrophy (X-ALD) is a neurodegenerative metabolic disorder inherited in an X-linked recessive manner. During the last 15 years the authors diagnosed 21 patients with different X-ALD phenotypes. The patients were followed for 1–12 years. Progressive cerebral form of the disease (cALD) was identified in eight boys and in two adolescent patients. Chronic adrenomyeloneuropathy (AMN) and adrenal insufficiency only (ADO) were diagnosed in six adolescent/ adult men and in two male patients (aged 6 and 26 years), respectively. Genotyping of relatives in affected families revealed three asymptomatic males with X-ALD (2, 6 and 29 years old, respectively). Each of 21 patients had elevated concentrations of very long chain fatty acids (VLCFA) in plasma and each carried a pathogenic mutation in the ABCD1 gene. The prognosis is not favorable in the majority of patients. However, early diagnosis, carrier identification and genetic prevention represent an important help for the affected families. Bone marrow transplantation is effective only in early diagnosed cALD patients. Dietary therapy includes low fat diet with Lorenzo’s oil, which inhibits endogenous VLCFA synthesis. It is used in males with a risk of development of cerebral ALD. The effect of dietotherapy in men with AMN is not fully proven.

        Key words: ABCD1 gene, Addison disease, adrenomyeloneuropathy, very long chain fatty acids (VLCFA), X-linked adrenoleukodystrophy, peroxisome