Juvenile metachromatic dystrophy and bone marrow transplantation

Groeschel S, Kühl JS, Bley AE, Kehrer C, Weschke B, Döring M, Böhringer J,

Schrum J, Santer R, Kohlschütter A, Krägeloh-Mann I, Müller I. Long-term Outcome

of Allogeneic Hematopoietic Stem Cell Transplantation in Patients With Juvenile

Metachromatic Leukodystrophy Compared With Nontransplanted Control Patients. JAMA

Neurol. 2016 Jul 11. doi: 10.1001/jamaneurol.2016.2067. [Epub ahead of print]

Abstract

IMPORTANCE:

Allogeneic hematopoietic stem cell transplantation (HSCT) has been the only treatment option clinically available during the last 20 years for juvenile metachromatic leukodystrophy (MLD), reported with variable outcome and without comparison with the natural course of the disease.

OBJECTIVE:

To compare the long-term outcome of patients who underwent allogeneic HSCT with control patients who did not among a cohort with juvenile MLD.

DESIGN, SETTING, AND PARTICIPANTS:

Patients with juvenile MLD born between 1975 and 2009 and who received HSCT at a median age of 7 years (age range, 1.5-18.2 years) and nontransplanted patients with juvenile MLD born between 1967 and 2007 were included in this case-control study. The median follow-up after HSCT was 7.5 years (range, 3.0-19.7 years). Patients underwent HSCT at 3 German centers between 1991 and 2012. The analysis was done between July 2014 and August 2015.

MAIN OUTCOMES AND MEASURES:

Survival and transplantation-related mortality, loss of gross motor function (Gross Motor Function Classification in MLD), loss of any language function, and magnetic resonance imaging (MRI) severity score for cerebral changes. To explore prognostic factors at baseline, patients who underwent HSCT (hereafter, transplanted patients) were a priori divided into stable vs progressive disease, according to gross motor and cognitive function.

RESULTS:

Participants were 24 transplanted patients (11 boys, 13 girls) and 41 control patients (22 boys, 19 girls) who did not receive transplantation (hereafter, nontransplanted patients) with juvenile MLD. Among the transplanted patients, 4 children died of transplantation-related mortality, and 2 additional children died of rapid MLD progression 1.5 and 8.6 years after HSCT, resulting in a 5-year survival of 79% (19 of 24). Among the nontransplanted patients, 5-year survival after disease onset was 100% (41 of 41). However, 11 died of MLD progression, resulting in similar overall survival within the observation period. Nine of the long-term survivors after HSCT had disease progression, while 11 showed stable disease. Compared with the nontransplanted patients, the transplanted patients were less likely to lose their gross motor or language function and demonstrated significantly lower MRI severity scores at the latest examination. Patients after HSCT were more likely to have a stable disease course when undergoing HSCT at an early stage with no or only mild gross motor deficits (Gross Motor Function Classification in MLD level 0 or 1) and an IQ of at least 85, when age at disease onset was older than 4 years, or when MRI severity scores were low (preferably ≤17).

CONCLUSIONS AND RELEVANCE:

Among patients with juvenile MLD, patients who underwent HSCT had a better gross motor and language outcome and lower MRI severity scores compared with nontransplanted patients. Transplantation at a presymptomatic or early symptomatic stage of juvenile MLD is associated with a reasonable chance for disease stabilization.

Chen X, Gill D, Shaw P, Ouvrier R, Troedson C. Outcome of Early Juvenile Onset

Metachromatic Leukodystrophy After Unrelated Cord Blood Transplantation: A Case

Series and Review of the Literature. J Child Neurol. 2016 Mar;31(3):338-44.

Abstract

The purpose of this study was to determine whether transplantation of umbilical cord blood from unrelated donors before the development of symptoms could halt the progression of early juvenile onset cases of MLD in whom the disease was diagnosed based on the family history. Three asymptomatic children (aged 2 years 4 months, 2 years 8 months and 5 years 5 months, two of whom were sisters) underwent unrelated umbilical cord blood transplantation (UCBT) and two untreated symptomatic siblings were included in the study. In 14-year and 6-year follow-ups after transplantation, clinical examination, ARSA enzyme levels, neurophysiological, neuroimaging, and psychological status were assessed. All three transplanted patients remain well, and the parameters evaluated remain stable. Of the treated patients, the two sisters had ongoing evidence of demyelinating sensorimotor neuropathy on nerve conduction tests, and with a early sensorimotor neuropathy in the older sister , and the other patient has mild intellectual impairment. One of the two un-transplanted controls, 15 years after MLD diagnosis, has relentlessly progressed to full dependency with epilepsy, severe mental retardation, dystonic movements, dysphagia and recurrent respiratory problems. Six years after diagnosis, the other control has a slowly progressive course with spastic dystonic quadriplegia, epilepsy, dysphagia, continual drooling and incontinence. Our data show that, in comparison with their untreated siblings, UCBT significantly slowed the progression of the disease in the treated patients. We conclude that UCBT benefits children with pre-symptomatic early juvenile onset MLD by favourably altering the natural history of the disease.