Krabbe disease involves the accumulation of neurotoxic metabolites due to lysosomal galactocerebrosidase enzyme deficiency, which results in widespread demyelination of central and peripheral nerves. Generally, Krabbe disease presents as spastic paraplegia with a slow progressive course; however, some cases may show clinical symptoms similar to those of chronic inflammatory demyelinating polyneuropathy (CIDP). No previously reported studies have investigated the efficacy of intravenous immunoglobulin (IVIg) for treating Krabbe disease, and reporting a case involving IVIg treatment may be informative in the clinical setting. A 14-year-old girl who developed Guillain-Barré syndrome-like limb weakness was administered IVIg, and her limb weakness improved. At 16 years old, she developed abnormal sensory perception and weakness of both upper limbs. A nerve conduction study revealed demyelination, which led us to suspect CIDP. IVIg was administered, and her symptoms gradually improved. A nerve biopsy, enzyme activity, and genetic test results indicated adult Krabbe disease. In some cases, IVIg may be an effective treatment for Krabbe disease.

Late-onset adult Krabbe disease is a very rare demyelinating leukodystrophy, affecting less than 1 in a million people. Hematopoietic stem cell transplantation (HSCT) strategies can stop the accumulation of toxic metabolites that damage myelin-producing cells. We used quantitative advanced imaging metrics to longitudinally assess the impact of HSCT on brain abnormalities in adult-onset Krabbe disease. A 42-year-old female with late-onset Krabbe disease and an age/sex-matched healthy control underwent annual 3T MRI (baseline was immediately prior to HSCT for the Krabbe subject). Imaging included conventional scans, myelin water imaging, diffusion tensor imaging, and magnetic resonance spectroscopy. Brain abnormalities far beyond those visible on conventional imaging were detected, suggesting a global pathological process occurs in Krabbe disease with adult-onset etiology, with myelin being more affected than axons, and evidence of wide-spread gliosis. After HSCT, our patient showed clinical stability in all measures, as well as improvement in gait, dysarthria, and pseudobulbar affect at 7.5 years post-transplant. No MRI evidence of worsening demyelination and axonal loss was observed up to 4 years post-allograft. Clinical evidence and stability of advanced MR measures related to myelin and axons supports HSCT as an effective treatment strategy for stopping progression associated with late-onset Krabbe disease.

A case of late-infantile Krabbe disease in a patient who presented with developmental regression and spastic quadriplegia in late infancy is reported. Brain magnetic resonance imaging (MRI) at 11 months of age showed predominant corticospinal tract involvement, which usually appears in adult Krabbe disease. Galactocerebrosidase activity in lymphocytes and skin fibroblasts was very low. Genetic testing revealed compound heterozygous mutations of the galactocerebrosidase (GALC) gene, c.635_646 delinsCTC and c.1901T>C [p.L618S], both of which are known pathogenic mutations. It has been reported that the c.1901T>C [p.L618S] mutation is associated with the late-onset phenotype and, in a past case, a homozygous mutation at this location showed predominant corticospinal tract involvement on MRI. Although further analysis is needed to identify the pathophysiological mechanism, this combination of mutations is likely to be associated with this unusual MRI finding in late-infantile Krabbe disease. Because these types of mutations are common for Japanese patients, it is possible that there are more undiagnosed and late-diagnosed patients of late-infantile Krabbe disease who display limited lesions on MRI. Pediatricians should be aware that patients with late-infantile Krabbe disease can present with predominant corticospinal tract involvement on MRI.