Autosomal Recessive Myotonia Congenita, A Muscle Channelopathy, Presenting in Nigerian Siblings: A Report.

Abstract

Background: The muscle diseases are frequently encountered in medical clinics in Nigeria. In many cases however they are not optimally managed. The ion channel diseases, ‘channelopathies', are a group of muscle disorders that share a lot of clinical similarity. Misdiagnosis can occur especially in resource poor settings with paucity of neurologists and diagnostic tools.
Method: A case report of two young Nigerian siblings aged 13 and 15 years who have the clinical features of autosomal recessive myotonia congenita (Becker disease), one of the muscle channelopathies, is presented. The relevant literature is reviewed.
Results: A 15 year old Nigerian male presented with a 7 year history of progressive weakness of the legs and a 4 year history of difficulty in lifting heavy loads with the arms. There are no bulbar or cardiac symptoms. He had generalized muscle hypertrophy with percussion and exercise induced myotonia. Available investigations showed no cardiac involvement. The 13 year old younger brother similarly presented with a 4 year history of difficulty in initiating movements with the legs which was within a few weeks by weakness of the upper limbs. He also had no cardiac or bulbar symptoms. The physical findings were similar. The parents could not afford to continue with most investigations but the creatine kinase was elevated in the elder sib. Other members of the family were apparently normal. They were lost to follow up.
Conclusion: The pervading poor socioeconomic status of many Nigerians, the dearth of neurologists, the lack of sophisticated diagnostic tools and suboptimal laboratory backup all contribute to the difficulty encountered in managing muscle disease in the country. There is a need for concerted efforts to improve access to affordable and effective medical care to make for proper diagnosis and treatment of cases of muscle diseases.


Keywords: Myotonia congenita, Nigerian siblings, case report

Journal of College of Medicine Vol. 13 (2) 2008: pp. 133-137