A Case Report: Patient With X-Linked Adrenoleukodystrophy - Adrenomyeloneuropathy Phenotype

Introduction X-linked adrenoleukodystrophy (ADL) is a rare genetic disorder caused by a congenital defect in the ABCD1 gene (1,2). Its onset age varies widely and disease progression is usually slow but unpredictable (2,3). Clinical presentation might include adrenal insufficiency, myelopathy, polyneuropathy, and leukodystrophy (1-4). Case Presentation A 31-year-old man complained of leg weakness and spasticity, which worsened with physical activity. In addition, the patient experienced disrupted sleep due to night-time leg myoclonus. Symptoms progressed for 6 years. His medical history is significant for primary Adisson’s disease, diagnosed in 2009, and irritable bowel syndrome (continuous complaints of frequent defecation, changes in stool consistency, and abdominal pain). The family history is relevant as the patient's mother and grandfather were diagnosed with Parkinson's disease. During a neurological examination, increased muscle tone is observed in both legs, reflexes in the legs are accentuated, and a pathological Babinski reflex is present on both sides. An MRI of the brain and spinal cord was conducted - no pathological changes in the intensity of the MR signal were detected. Sanger sequencing of the ABCD1 gene coding regions revealed a potentially pathogenic hemizygous variant NM_000033.4(ABCD1):c.[1772G>C];[0], which is responsible for an amino acid change in the structure of the protein NP_000024.2:p.[(Arg591Pro)];[(0)]. The patient's symptoms are currently more consistent with an adrenomyeloneuropathic (AMN) form of the disease. Discussion The estimated prevalence of ALD is 1:17000 (1,2). Several clinical phenotypes of ALD exist - AMN is the most common for adult males (1-3). Every young male with primary adrenal insufficiency should be suspected of ALD; neurological deficits usually start to show later in life and have a wider differential diagnosis (2-4). There is no current treatment for AMN, therefore timely diagnosis is required for the best multidisciplinary supportive care (4,5). Conclusions This clinical case highlights the importance of considering congenital disorders in the differential diagnosis of a young patient presenting with a history of unexplained and debilitating symptoms. Early recognition and timely referral for genetic counseling can improve diagnostic accuracy and patient care.