Familial spinocerebellar degeneration as an expression of adrenoleukodystrophy

X-linked cerebral adrenoleukodystrophy

A man in his 30s presented with a 6-month history of progressive left face, arm and leg weakness. Medical history included epilepsy and vitamin B12 deficiency. Three maternal second degree relatives died before the age of 7 from various neurological disorders. Examination revealed a mild left facial droop and weakness of the left shoulder, hip and ankle. Reflexes were symmetrical and tone was normal. Differential diagnosis included glioma, subacute infarction, lymphoma and demyelination. MRI brain showed an extensive right sided subcortical white matter lesion, with extension into the brainstem. The patient's weakness progressed over 3 months. Brain biopsy showed evidence of demyelination and gliosis. A pathological diagnosis of tumefactive multiple sclerosis was made, but also rare metabolic disorders such as X-linked adrenoleukodystrophy (X-ALD) were proposed. Serum very long-chain fatty acids were significantly elevated. Genetic testing showed a mutation in the ABCD1 gene, confirming a diagnosis of X-ALD.

Adult-onset cerebello-brainstem dominant form of X-linked adrenoleukodystrophy presenting as multiple system atrophy: case report and literature review

X-linked adrenoleukodystrophy (X-ALD) is the most common peroxisomal disorder and is caused by ABCD1 mutations. A cerebello-brainstem dominant form that mainly involves the cerebellum and brainstem is summarized in a review of the literature, with autopsy-confirmed cases exceedingly rare. We report a 69-year-old White man who was diagnosed with this rare disorder and describe neuropathologic, ultrastructural and genetic analyses. He did not have adrenal insufficiency or a family history of X-ALD or Addison's disease. His initial symptom was temporary loss of eyesight at age 34 years. His major symptoms were chronic and progressive gait disorder, weakness in his lower extremities and spasticity, as well as autonomic failure and cerebellar ataxia suggesting possible multiple system atrophy (MSA). He also had seizures, hearing loss and sensory disturbances. His brain MRI showed no obvious atrophy or significant white matter pathology in cerebrum, brainstem or cerebellum. He died at age 69 years with a diagnosis of MSA. Microscopic analysis showed mild, patchy myelin rarefaction with perivascular clusters of PAS-positive, CD68-positive macrophages in the white matter most prominent in the cerebellum and occipital lobe, but also affecting the optic tract and internal capsule. Electron microscopy of cerebellar white matter showed cleft-like trilamellar cytoplasmic inclusions in macrophages typical of X-ALD, which prompted genetic analysis that revealed a novel ABCD1 mutation, p.R163G. Given the relatively mild pathological findings and long disease duration, it is likely that the observed pathology was the result of a slow and indolent disease process. We described a patient who had sporadic cerebello-brainstem dominant form of X-ALD with long clinical course, mild pathological findings, and an ABCD1 p.R163G substitution. We also review a total of 34 cases of adult-onset cerebello-brainstem dominant form of X-ALD. Although rare, X-ALD should be considered in the differential diagnosis of MSA.

Clinical and genetic aspects in twelve Korean patients with adrenomyeloneuropathy

PURPOSE

This study was designed to investigate the characteristics of Korean adrenomyeloneuropathy (AMN) patients.

MATERIALS AND METHODS

We retrospectively selected 12 Korean AMN patients diagnosed by clinical analysis and increased plasma content of very long chain fatty acids.

RESULTS

All 12 patients were men. Patient ages at symptom onset ranged from 18 to 55 years. Family history was positive in two patients. The phenotype distributions consisted of AMN without cerebral involvement in seven patients, AMN with cerebral involvement in two patients, and the spinocerebellar phenotype in three patients. Nerve conduction studies revealed abnormalities in four patients and visual evoked tests revealed abnormalities in three patients. Somatosensory evoked potential tests revealed central conduction defects in all of the tested patients. Spinal MRI showed diffuse cord atrophy or subtle signal changes in all 12 patients. Brain MRI findings were abnormal in six of the nine tested patients. These brain abnormalities reflected the clinical phenotypes. Mutational analysis identified nine different ABCD1 mutations in 10 of 11 tested patients. Among them, nine have been previously reported and shown to be associated with various phenotypes; one was a novel mutation.

CONCLUSION

In conclusion, the present study is the first to report on the clinical and mutational spectrum of Korean AMN patients, and confirms various clinical presentations and the usefulness of brain MRI scan.

Leukodystrophies: classification, diagnosis, and treatment

BACKGROUND

The leukodystrophies are a heterogeneous group of diseases, which primarily affect white matter. Symptomatic patients are frequently misdiagnosed and the leukodystrophies are collectively under recognized. However, with ongoing research and increased availability of neuroimaging, our understanding of these diseases is increasing at a steady rate. Recent advances in the diagnosis and treatment of certain forms of leukodystrophy should prompt increased awareness of these diseases in clinical practice.

REVIEW SUMMARY

The clinical features, pathophysiology, and therapeutic approach to these diseases are described. Particular emphasis is placed on genetic and pathophysiologic mechanisms, imaging patterns, screening of other family members and, where available, treatment options and resources.

CONCLUSIONS

With more widespread use of neuroimaging, both pediatric and adult neurologists will increasingly be confronted with white matter disorders. Neurologists should have an approach to the recognition, diagnosis, and management of white matter diseases in general and the leukodystrophies in specific.

A case of adrenoleukodystrophy presenting as progressive cerebellar dysfunction

X-linked adrenoleukodystrophy (X-ALD) is a hereditary neurological disorder affecting the nervous system and adrenal cortex. The phenotype of X-ALD ranges from the rapidly progressive cerebral form to milder adrenomyeloneuropathy. However, cerebellar manifestations are rare. We report a case of adrenoleukodystrophy presenting as progressive cerebellar dysfunction resembling olivopontocerebellar degeneration, with a review of the literature

A novel point mutation in X-linked adrenoleukodystrophy presenting as a spinocerebellar degeneration

X-linked adrenoleukodystrophy (ALD) usually presents in childhood as severe cerebral demyelination accompanied by axonal loss or in adults as a progressive spinal cord syndrome (adrenomyeloneuropathy). Rarely, patients present with adult onset spinocerebellar ataxia. We performed mutation analysis in a family with several members who had this rare phenotype and identified a single nucleotide deletion in exon 2 of the ALD gene. This is the first mutation analysis to be reported in this unusual phenotypic variant of ALD and the first deletion to be reported in exon 2.

X linked adrenoleukodystrophy: clinical presentation, diagnosis, and therapy

X linked adrenoleukodystrophy (X-ALD) is an inherited disorder of peroxisomal metabolism, biochemically characterised by accumulation of saturated very long chain fatty acids. Accumulation of these fatty acids is associated with cerebral demyelination, peripheral nerve abnormalities, and adrenocortical and testicular insufficiency. The lowest estimated birth incidence is one per 100,000. At least six phenotypes can be distinguished, of which the two most frequent are childhood cerebral ALD and adrenomyeloneuropathy. The X-ALD gene has been identified, but thus far no relation between genotype and phenotype has been found. Diagnosis is relatively easy and can be confirmed reliably, and prenatal testing is possible in affected families. Several therapeutic options, some with promising perspectives, are available. Neurologists and other physicians seem not to be familiar with the many facets of X-ALD. In this review, the clinical presentation, the relative frequencies of the different phenotypes, and the diagnostic and therapeutic options are presented.

Molecular analysis of X-linked adrenoleukodystrophy patients

A molecular analysis of 4 Japanese adrenoleukodystrophy (ALD) patients was carried out, according to the recently published report on ALD gene cDNA. In a Southern blot analysis, we were not able to detect a large deletion in all patients. In a Northern blot analysis, no mRNA was detected in one patient, while the others had normal mRNA in both size and amount. Three patients had missense mutations including; 534Pro-->Leu (1987C-->T), 660Arg-->Trp (2364C-->T), and 512Gly-->Ser (1920G-->A), respectively. These mutations existed in the C-terminal region conserved in the ATP-binding cassette superfamily of transporters. In a Western blot analysis using polyclonal antibodies against the C-terminal peptide as well as the whole peptide of ALD protein, no 80 kDa protein was found in any of the 4 patients, which was observed in the control cells. The ALD protein in 3 patients with a missense mutation might be degraded immediately after translation because of the unstable higher structure or by the disruption of the hitherto unknown targetting signal to the peroxisome. The molecular analysis of the ALD gene as done in this study is thus considered to be the first step to further elucidate the pathogenic mechanism of ALD.

Ataxic variant of adrenoleukodystrophy: MRI and CT findings

A 28-year-old man developed slowly progressive dysarthria and gait disturbance over 7 years. Neurological examination revealed marked ataxia of articulation and gait, mild ataxia and spasticity of all four limbs without intellectual, visual, auditory, sensory or sphincter dysfunction. No physical signs of adrenal hypofunction were found. However, analysis of fatty acid of plasma sphingomyelin showed an increase in very long chain fatty acids, compatible with the diagnosis of adrenoleukodystrophy. Computed tomography disclosed marked atrophy of the cerebellum and pons, and bilateral low-density lesions in the deep while matter of the cerebellum. Magnetic resonance imaging showed these lesions more clearly, as well as other lesions in the middle and superior cerebellar peduncles, despite the absence of cerebral white matter involvement at the time of presentation. This is a rare case of adrenoleukodystrophy presenting as spinocerebellar degeneration and showing marked atrophy and several parenchymatous lesions of the cerebellum and brain stem.

The contribution of pathology to the study of storage disorders

Our purpose is to illustrate some contributions of pathology to a better knowledge of metabolic disorders affecting the brain and visceral organs. Four groups of diseases are used to that effect. A comparative study of pre- and postnatal examples of mucopolysaccharidoses I, II and III reveals for example that severe neuronal lesions are already found in fetuses and that a rough parallelism exists between the maturation of neurons and the progressive intralysosomal accumulation of undigested metabolites. The study of four patients with I-cell disease shows that the intralysosomal storage occurs nearly exclusively in fibroblasts. Since the enzyme defect has also been found in non-mesenchymal cells, other mechanisms for a proper processing of lysosomal enzymes must be available in the intact cells. Adrenoleukomyeloneuropathy is used to demonstrate that the morphological features witnessing the accumulation of the very long chain fatty acids can be different in the central and in the peripheral nervous system. Finally, juvenile dystonic lipidosis illustrate the heterogeneity of the conditions grouped under the denomination of sphingomyelinoses. These few examples confirm the role of pathology in the diagnosis of metabolic disorders and in the study of their physiopathogenesis.