Last modified: 2018-09-09
Abstract
Background: FKRP congenital muscular dystrophy is a rare congenital musclar dystrophy which is allelic to limb girdle muscular dystrophy 2I. In forms a significant proportion of CMD in the British Isles. It results in a slowly progressive neuromuscular weakness acompanied by skeletal abnormalities and progressive respiratory failure. Neuromuscular transmission abnormalities have not been described in this disorder previously.
Case: We present the case of a male infant with congenital hypotonia, ventriculomegaly and raised creatine kinase. He presented with acute weakness and respiratory failure in association with adenovirus infection at the age of 7 months. Repetitive nerve stimulatino showed a clear decremental response so treatment with pyridostgmine was commenced. This resulted in a significant improvement in muscle strength. 3,4-diamonpyridine was also introduced which demonstrated additional benefit. Congenital myasthenic syndrome was consider but genetic testing did not identify any pathogenic mutations. FKRP testing was undertaken as there was a family history of this disorder. This revealed compound heterozygous mutations in FKRP whcih have previously been recognised as pathogenic.
Discussion:
FKRP congenital muscular dystrophy has not previously been linked to neuromuscular transmission abnormality. This case demonstrates neurophysiological and clinical evidence of this. The pathological basis for this is not clear but investigation for neuromuscular transmission defects in other cases of FKRP congenital muscular dystrophy is recommended.