Adrenoleukodystrophy Masquerading as Chronic Immune Demyelinating Polyradiculoneuropathy in a Patient with HIV
Sarah Guistolisi1, Sarah Kelly2, Aaron Carlson3, Daniel Pastula1, Rumyar Ardakani4
1University of Colorado, Department of Neurology, 2University of Colorado, 3Neurology, University of Colorado, School of Medicine, Department of Neurology, 4Neuro-Infectious Diseases Group
Objective:
To describe a challenging case of adrenomyeloneuropathy and cerebral inflammatory adrenoleukodystrophy in an adult with HIV.
Background:
X-linked adrenoleukodystrophy (ALD) is the most common peroxisomal disorder with an incidence of approximately 1:11000 in the U.S. Clinical phenotypes vary including adrenal insufficiency, adrenomyeloneuropathy, and cerebral ALD (cALD): an inflammatory leukodystrophy that is frequently progressive without therapeutic intervention. Hematopoietic stem cell transplantation remains the best treatment to halt cALD, and is best given early, emphasizing the need for early recognition.
Design/Methods:
Case report
Results:
A 33-year-old HIV-positive male on antiretroviral therapy (CD4+ count 240 cells/mm3, undetectable viral load) presented with one year of subacute-on-chronic progressive weakness (previously diagnosed as chronic inflammatory demyelinating polyneuropathy) and three months of vision loss and incontinence. Examination revealed decreased muscle bulk, distal-predominant, symmetric weakness with bilateral foot drop, and areflexia in the lower extremities with increased reflexes in the upper extremities. MRI demonstrated thickened and enhancing lumbosacral nerve roots, atrophy of the thoracic spine, and largely symmetric T2 prolongation throughout the optic tracts and corticospinal tract in brain, brainstem, and spinal cord. Areas of enhancement were seen within corticospinal tract in the pons and midbrain, as well as within the optic tracts. EMG and sural nerve biopsy were nondiagnostic. Diagnostic consideration was given to HIV myelopathy, however our patient lacked history of long-standing, poorly controlled HIV. Given spinal cord atrophy and myeloneuropathic signs, very long chain fatty acids (VLCFA) were sent and returned with an abnormal C26:0:C22.0 ratio of 0.091; subsequent genetic testing confirmed a pathogenic variant in ABCD1.
Conclusions:
Adrenoleukodystophy is a challenging diagnosis as its presentation can mimic other conditions. In this case, the presence of HIV contributed to diagnostic uncertainty. Clinicians should consider testing for VLCFA in patients with unexplained myeloneuropathy.