Recep AYGÜL, Dilcan KOTAN, Gökhan ÖZDEMİR

Four cases of myotonia congenita in a Turkish family

Konjenital myotoni, otozomal dominant veya otozomal resesif kalıtılan nadir bir kas hastalığıdır ve ağrısız myotoni ile karakterizedir.Kırk dört yaşında anne ile ailenin bir erkek ve bir kız çocuğu ellerini gevşetmede güçlük, yürümeye başlamakta zorlanma ve çiğneme sırasında tutukluk şikayetleri ile kliniğimize başvurdu. Ailenin 16 yaşındaki diğer kız çocuğunun herhangi bir yakınması yoktu. Anne, babası ve iki kız kardeşinin benzer hastalığı olduğunu, fakat erkek kardeşinin ise sağlıklı olduğunu bildirdi. Soy ağacı analizi hastalığın üç kuşaktır devam ettiğini ve otozomal dominant geçişli olduğunu gösterdi. Olguların nörolojik muayenesinde eller, kol ve bacak kaslarında aksiyon ve perküsyon miyotonisi gözlendi. Asemptomatik kız çocuğu da jeneralize miyotoniye sahipti. Tüm olguların iğne elektromyografisi muayene edilen kaslarda yaygın myotonik deşarjlar ortaya çıkardı. Olgular, ailenin üç kuşağında konjenital myotoni olmasından dolayı sunuldu. Bu olgu çalışması, asemptomatik olgularda myotonik hastalıkların belirlenmesinde EMG çalışmalarının da faydalı olduğunu ortaya koymaktadır.

Bir Türk ailesinde dört konjenital myotoni olgusu

Myotonia congenita is a rare muscular disorder with autosomal dominant or autosomal recessive inheritance, and is characterized by painless myotonia.A 44-year-old mother presented at our clinic with a son and a daughter, all sharing the same complaints of difficulty in relaxing their hands and beginning to walk, and spasms during chewing. The family had also another 16-year-old daughter, but she had no such complaints. The mother reported that her father and 2 sisters had the same disease, but that her brother was healthy. Their pedigree analysis revealed that the disease was present for 3 generations and had an autosomal dominant trait. During the neurologic examination of cases, action and percussion myotonia were observed in the hand, arm, and leg muscles. Her asymptomatic daughter had also generalized myotonia. Needle electromyography of all cases revealed generalized myotonic discharges in the muscles examined. The cases are presented due to the presence of MC in 3 generations of the family. This case study reveals that EMG studies are useful in determining myotonic disorders in asymptomatic cases.

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