[Hereditary neuromuscular diseases in paediatrics. Our experience over the last 14 years]

Hereditary neuromuscular diseases are disorders which can vary largely in their age of onset, symptoms and severity. Many are severe, disabling and have an important personal, familial and social impact and can restrict the prognosis for survival. The constant progress being made in diagnostics makes it necessary to continually update knowledge and information.

We carried out a review of the hereditary neuromuscular diseases contained in the Neuropaediatrics database at the Hospital Miguel Servet in Zaragoza from May 1990 to October 2004.

Of the 7,805 patients in the database, 123 (1.5% of the total) were patients with hereditary neuromuscular diseases, of whom 71 were males and 52 females. These included: 35 sensory-motor hereditary neuropathies, 17 dystrophinopathies, 10 myotonic dystrophies, 10 spinal muscular atrophies, four merosin-deficient congenital dystrophies, four other muscular dystrophies, three mitochondrial myopathies, three myasthenias, two familial neuropathies with insensitivity to pain, two Friedreich's ataxias, one familial neuropathy with liability to pressure palsies, one case of Walker-Warburg syndrome, five polyneuropathies associated to leukodystrophy and another 25 cases that could not be classified. Genetic studies provided a diagnosis in 36 cases (29.2%): nine myotonic dystrophies, eight dystrophinopathies, eight cases of spinal muscular atrophy, four demyelinating sensory-motor hereditary neuropathies, two instances of Friedreich's ataxia, two limb-girdle muscular dystrophies, one congenital myasthenia, one McArdle's disease and one case of Kearns-Sayre syndrome.

Genetic studies enable us to establish diagnoses that were previously limited to the realm of assumption, and allow us to avoid the need for muscle tissue biopsies, which is a welcome development, especially when dealing with children. Immunohistochemical studies need to be updated and biological samples should be systematically saved in cases where no diagnosis is reached.