Clinical and biochemical heterogeneity of globoid cell leukodystrophy

L-cycloserine slows the clinical and pathological course in mice with globoid cell leukodystrophy (twitcher mice)

Globoid cell leukodystrophy (Krabbe's disease) is an autosomal recessive disease that affects the lysosomal enzyme galactosylceramidase. Galactosylceramidase removes galactose from galactosylceramide and psychosine, which are derived from sphingosine. In the present study, L-cycloserine (an inhibitor of 3-ketodyhydrosphingosine synthase) was administered to the twitcher mouse, an authentic model of globoid cell leukodystrophy. Twitcher mice treated with L-cycloserine had a significantly longer life span and a delayed onset of weight loss than vehicle-injected twitcher mice. Pathological features such as macrophage infiltration and astrocyte gliosis also were less in treated twitcher mice. These results indicate that substrate reduction therapy may have therapeutic value for individuals with residual enzymatic activity, e.g., individuals with late onset disease or individuals with partial enzyme replacement via bone marrow transplantation. In these cases, a reduction in galactosylceramide and psychosine synthesis would enable residual enzymatic activity to keep up with the accumulation of these substrates that would otherwise lead to pathology.

Adult onset Krabbe's leukodystrophy: a report of 2 cases

Krabbe's disease with adult onset is rare; neurological symptoms begin in childhood or at a juvenile age. Two brothers with adult onset of the disease are here reported; 1 sibling developed parapareto-ataxic gait while the other was asymptomatic. Magnetic resonance imaging showed areas of demyelination in the white matter of the brain, while nerve conduction was completely normal. In both patients deficiency of galactosylceramide beta-galactosidase was comparable to the infantile form.

Krabbe's disease presenting as a peripheral neuropathy

A 13-year-old female initially presented with scoliosis and pes cavus. Initial examination revealed distal lower extremity weakness and sensory loss, as well as greater auricular nerve hypertrophy. There was a Babinski sign on the right. Nerve conduction velocities were consistent with a demyelinating neuropathy. Four years after initial presentation she developed lower extremity spasticity and bilateral Babinski signs. Magnetic resonance imaging of the brain showed diffuse white matter disease. Laboratory evaluation revealed an abnormally low galactocerebroside beta-galactosidase level. Nerve biopsy demonstrated inclusions consisting of globoid clusters and evidence of demyelination. DNA analysis was used to identify mutations consistent with Krabbe's disease. Patients presenting with an atypical peripheral neuropathy should be evaluated for Krabbe's disease.

Adult-onset Krabbe's disease in siblings with novel mutations in the galactocerebrosidase gene

Krabbe's disease or globoid cell leukodystrophy is a rare demyelinating disorder of the central and peripheral nervous systems, the diagnosis of which is based on clinical findings and the determination of low to absent functional activity of the enzyme beta-galactocerebrosidase. We report the presentation of late-onset Krabbe's disease in 2 siblings, a 17-year-old boy and his 16-year-old sister, both with marked deficiency of the enzyme beta-galactocerebrosidase. Only the older sibling manifested clinical signs and symptoms of the disease, while the younger sister remained asymptomatic to date. Molecular analyses disclosed the presence in this family of two novel single point mutations within the gene for galactocerebrosidase.

MRI and CT in Krabbe's disease: case report

A case of infantile Krabbe's disease was first recognised as areas of relatively increased density on CT in the thalamus lateral geniculate body and dentate nucleus. These sites were subsequently shown on MRI to have a paramagnetic effect, being characterised by short T2 and T1. Subsequent examinations showed development of atrophy and high signal in white matter.

Clinical onset and MRI features of Krabbe's disease in adolescence

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Somatic cell genetic analysis of the galactocerebrosidase gene: lack of complementation in human Krabbe disease/twitcher mouse cell hybrids

The inherited deficiency of galactosylceramide beta-galactosidase (E.C. 3.2.1.46: galactocerebrosidase) activity results in globoid cell leukodystrophy in humans (Krabbe disease) and in mice (twitcher mutant). To determine whether Krabbe patients' cells complement twitcher cells to produce, in hybrid combination, greater than deficient levels of galactocerebrosidase activity, five separate crosses were made between an established twitcher mouse cell line and five cell strains from unrelated Krabbe disease patients. A total of 57 twitcher mouse/Krabbe somatic cell hybrid lines developed from all of these crosses were deficient in galactocerebrosidase activity despite the presence of human chromosomes 14 or 17, which have been previously implicated as bearing the galactocerebrosidase gene. A control cross between twitcher mouse/positive control human fibroblasts resulted in 14 of 21 independent hybrid lines that expressed higher than deficient levels of galactocerebrosidase activity. The lack of complementation between Krabbe disease patient and twitcher mutant mouse cells provides further evidence that the twitcher mouse is an authentic murine model for Krabbe disease and supports the hypothesis that the mutations in both species are within the structural gene for the galactocerebrosidase enzyme.

Late-onset globoid cell leukodystrophy: unusual ultrastructural pathology and subtotal beta-galactocerebrosidase deficiency

An 11-year-old girl was found to have severely reduced beta-galactocerebrosidase activity as evidence of late-onset globoid cell leukodystrophy, while her mother had almost normal enzyme activity in circulating white blood cells. Clinically, the patient showed a remitting course marked by seizures, ataxia, white-matter disease on computed tomographic scan, and reduced conduction velocities of peripheral nerves. Symptoms improved somewhat around the age of 10 years. Two sural nerve biopsies, performed 6 years apart, disclosed a demyelinating neuropathy. By electron microscopy, membrane-bound vacuolar lysosomes in Schwann cells of myelinated axons, unlike the typical needlelike inclusions seen in classic infantile globoid cell leukodystrophy, were present in both specimens. Thus, clinical, morphologic, and biochemical data in this patient--and her mother--emphasize, compared with past reports on late-onset globoid cell leukodystrophy, considerable variation in the nosologic spectrum of late-onset globoid cell leukodystrophy and conspicuous differences from classic infantile globoid cell leukodystrophy.

Late juvenile-onset Krabbe's disease

Krabbe's disease is an autosomal recessive leukodystrophy characterized by a lack of galactocerebroside beta-galactosidase activity. In contrast to the classic early infantile-onset form of Krabbe's disease, less recognized, late-onset variants exist. The authors present a case of late juvenile-onset Krabbe's disease, including the associated magnetic resonance imaging (MRI) findings. Most patients with late-onset Krabbe's disease present with visual loss due to optic atrophy. Associated gait abnormalities and parental consanguinity should increase the clinician's suspicion that a child may have late-onset Krabbe's disease. Because of the prolonged survival in late-onset Krabbe's disease, the recent development of bone marrow transplantation for these patient makes diagnosis of this disorder particularly important.

A case of late variant form of infantile Krabbe disease with a partial deficiency of galactocerebrosidase

A female was diagnosed as a late variant form of infantile Krabbe disease at 1 year and 3 months because of the late onset of regressive clinical course, decreased motor nerve conduction velocities, high cerebrospinal protein concentration and partial deficiency of galactocerebrosidase (15.6%) in the cultured skin fibroblasts. She showed normal development until 8 months when she lost her ability of sitting alone after febrile infection, and died accidentally at 2 years and 4 months. A considerable residual enzyme activity may correlate to the milder clinical course of this case.

The inherited neurodegenerative disorders of childhood: clinical assessment

This review represents an examination of four groups of neurodegenerative diseases, namely the sphingolipidoses, the adrenoleukodystrophy complex, the neuronal ceroid lipofuscinoses, and the sialidoses/sialuria complex. Using a combination of clinical assessment, neuroradiologic appearance, and clinical neurophysiology, one may develop strategies that lead to specific chemical or biochemical determinations for specific diagnoses. In general, disorders of white matter may be distinguished from disorders of gray matter by their appearance on computed tomography and by abnormalities of nerve conduction velocities and auditory brain stem responses. In contrast, disorders of gray matter may be distinguished from disorders of white matter by their appearance on computed tomography and utilization of electroretinography, visual evoked responses, and, to a lesser extent, EEG findings. Where necessary, skin, conjunctival, or nerve biopsy may prove to be useful adjuncts to the diagnosis. Presently, treatment depends on prevention, although aggressive efforts are under way to establish corrective therapy by enzyme replacement. To this end, the use of already existing animal models may prove to be helpful.

Computed tomography and magnetic resonance imaging in late-onset globoid cell leukodystrophy (Krabbe disease)

A five-year-old white male presented with a history of progressive loss of vision that was subsequently followed by progressive corticospinal dysfunction. Evaluation revealed the presence of leukodystrophy which was confirmed by a deficiency of the enzyme, galactosylceramide beta-galactosidase. We present the clinical, computed tomographic, and magnetic resonance imaging features of this late-onset form of globoid cell leukodystrophy.

Fabry's disease with partially deficient hydrolysis of ceramide trihexoside

A report is presented on biochemical studies of the fibroblasts from a 26-year-old man with Fabry's disease whose clinical picture was atypical. The patient had severe pain in the extremities, but no angiokeratomas, corneal clouding or hypohidrosis. The trihexosylceramidase activity in the fibroblasts in vitro was deficient. The level and Km value of the residual activity were similar to levels seen in typical Fabry's patients. However, fibroblasts from the patient cultured in medium supplemented with [3H]ceramide trihexoside hydrolyzed the labeled ceramide trihexoside much higher than did cells from typical Fabry's patients, implying that the patient has a partial defect in hydrolysis of trihexosylceramide in cultured fibroblasts.