Delayed Dıiognosis of Congenital Myasthenic Syndrome

Öz

Congenital myasthenic syndromes (CMS) are rare, clinically and genetically heterogeneous group of disorders characterized with many genetic mutations causing neuromuscular transmission disfunctions. A 45 year old female patient with bilateral ptosis, ophthalmoplegia, dysphagia and proximal dominant weakness in all limbs was presented. We learned that she had walking disability, difficulty in standing up and fatigue since 2 year old. Antibody negative and thorax tomography normal patient had been followed up with the diagnosis of myasthenia gravis since 12 year old. Decrement response were achieved with 3 Hz repetetive stimulation. Muscular atrophy was observed in muscle biopsy compatible with neuromuscular junction disease. During follow up with the treatment of pridostigmin her complaints improved partially. Genotype and symptoms are not specific in CMS and has a wide spectrum. In the cases of unresponsive immunomodulatory therapy, with a detailed clinical history and muscle biopsy, the diagnosis should be kept in mind.

Anahtar Kelimeler

• congenital myasthenic syndromes,diagnosis; electrophysiology; muscle biopsy; gene mutation

Geç tanı konjenital miyastenik sendrom

Öz

Konjenital miyastenik sendrom (KMS) nadir görülen, çok sayıda gen mutasyonuna bağlı oluşabilen, nöromuskuler transmisyon disfonksiyonu ile karakterize klinik ve genetik açıdan heterojen bir hastalıktır. Bilateral pitoz, her yöne bakış kısıtlılığı, yutma güçlüğü ve tüm ekstremitelerde proksimal hakim güçsüzlük şikayetleri olan 45 yaşında kadın hasta sunuldu. Öyküsünde 2 yaşından beri olan yürüme güçlüğü, ayağa kalkmakta zorlanma ve çabuk yorulma olduğu öğrenildi. Oniki yaşından beri miyastenia gravis tanısıyla takip edilen hastanın antikorları negatif ve toraks tomografisi normaldi. Repetetif stimulasyonda 3 Hz uyarımla dekrement yanıt elde edildi. Ataklarda immunmodulatuar tedavilere yanıt alınamadı. Kas biopsisinde ise nöromuskuler kavşak hastalığı ile uyumlu kas atrofisi gözlendi. Takibimizde mestinon tedavisi almakta olan hastanın şikayetlerinde kısmi bir düzelme saptandı. KMS’de genotip ve semptomlar spesifik değildir ve geniş bir spektruma sahiptir. İmmunmodulatuar tedavilere yanıtsız olgularda  ayrıntılı anamnez ve kas biopsisi ile tanının akılda tutulması vurgulanmak amaçlandı.

Anahtar Kelimeler

• konjenital miyastenik sendrom,tanı; elektrofizyoloji;kas biopsisi;gen mutasyonu

Kaynakça

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