[Experience in molecular diagnostic in hereditary neuropathies in a pediatric tertiary hospital].

INTRODUCTION

Charcot-Marie-Tooth (CMT) is the most common hereditary sensory motor neuropathy. Advances in molecular diagnosis have increased the diagnostic possibilities of these patients.

PATIENTS AND

METHODS

Retrospective study of 36 pediatric patients diagnosed with CMT in a tertiary center in 2003-2015.

RESULTS

We found 16 patients were diagnosed by a duplication in PMP22; two cases were diagnosed of hereditary neuropathy with liability to pressure palsies, one with a point mutation in PMP22; a male with a mild demyelinating phenotype, without family history, was diagnosed with GJB1 mutation; in a patient with a peripheral hypotonia at birth and axonal pattern in EMG by mutation in MFN2; a gypsy patient, with consanguineous family, CMT4D, was identified by a mutation in the gene NDRG1; a patient with multiplex congenital arthrogryposis and vocal cord paralysis, whose mother had a scapular-peroneal syndrome, had a congenital spinal muscular atrophy with mild distal axonal neuropathy by mutation in gene TRPV4; three girls, from a gypsy consanguineous family, with axonal CMT with neuromyotonic discharges were diagnosed by a mutation in the gene HINT1; twelve patients haven't molecular diagnosis currently.

CONCLUSIONS

CMT1A predominated in our series (44%), as previous studies. We emphasize the description of a patient with a mutation in TRPV4 recently described as a cause of CMT2C and three cases, of gypsy consanguineous family, with the same mutation in HINT1 gene, recently described as a cause of axonal neuropathy with neuromyotonia, autosomal recessive (AR-CMT2). The proportion of patients without molecular diagnosis is similar to main European series.