Search

Metachromatic leukodystrophy (MLD) is a rare sphingolipid storage disorder caused by arylsulfatase A (ARSA) deficiency, resulting in central and peripheral demyelination. However, an uncommon form of MLD caused by saposin B deficiency is also described (around 10 mutations reported till date). MLD is a systemic disorder affecting the central and peripheral nervous system, gall bladder, and kidneys. Acute flaccid paralysis as the initial clinical presentation is previously known in ARSA-deficient MLD. Hereby, we report a child with acute flaccid paralysis with brain magnetic resonance imaging showing nonspecific periventricular leukodystrophy. He had progressive cognitive decline with gall bladder polyposis. ARSA levels were within normal limits. Leukodystrophy gene panel revealed a homozygous pathogenic deletion (Lys227del variant) in prosaposin (PSAP) gene. Hence, a final diagnosis of saposin B–deficient MLD was established. The index case highlights the importance of clinical and electrophysiological clues in the diagnosis of such atypical presentations of MLD. [ABSTRACT FROM AUTHOR]

Friedreich's ataxia (FRDA) is amultisystemdisease affecting the predominately nervous system, followed by muscle, heart, and pancreas. Current research focused on therapeutic interventions aimed at molecular amelioration, but there are no reliable noninvasive signatures available to understand disease pathogenesis. The present study investigates the alterations of plasma cell-free microRNAs (miRNAs) in FRDA patients and attempts to find the significance in relevance with the pathogenesis. Total RNA from the plasma of patients and healthy controls were subjected to miRNA microarray analysis using Agilent Technologies microarray platform. Differentially regulated miRNAs were validated by SYBR-green real-time polymerase chain reaction (Thermo Fisher Scientific). The study identified 20 deregulatedmiRNAs (false discovery rate < 0.01, fold change ≥ 2.0≤) in comparison with healthy controls; out of which 17 miRNAs were upregulated, and 3 miRNAs were downregulated. Target and pathway analysis of these miRNAs have shown association with neurodegenerative and other clinical features in FRDA. Further validation (n = 21) identified a set of significant (p < 0.05) deregulated miRNAs; hsa-miR-15a-5p, hsa-miR-26a-5p, hsa-miR-29a-3p, hsamiR- 223-3p, hsa-24-3p, and hsa-miR-21-5p in comparison with healthy controls. ThesemiRNAs were reported to influence various pathological features associated with FRDA. The present study is expected to aid in the understanding of disease pathogenesis. [ABSTRACT FROM AUTHOR]