Geç Tanı Almış Morquio Sendromu Olgusu

Abstract

Morquio Tip A Sendromu (MPS IVA) N-asetilgalaktozamin-6-sulfat sulfataz eksikliği ile ortaya çıkan, kornea ve kemikte keratan sülfat ve kondroitin-6-sulfat birikimi ile karakterize, otozomal resesif geçişli bir lizozomal depo hastalığıdır. Başlıca klinik bulgular; kısa boy, iskelet displazisi, dental anomaliler ve korneal bulutlanmadır. Bunlara sinirsel tip işitme kaybı, kalp kapağı hastalıkları, eklem laksitesi ve servikal myelopati eşlik edebilir. Merkezi sinir sistemi tutulumunun olmaması sebebiyle enzim replasman tedavisi ve gen tedavilerinin uygulanabileceği bir hastalık olarak kabul edilmektedir. Preklinik çalışmalarda enzim replasman tedavisi ile doku ve kandaki keratan sülfat oranında anlamlı düşüş gösterilmiştir. Ancak lizozomal depo hastalıklarında tedavinin başarılı olabilmesi hastalığın erken dönemlerinde başlanması ile mümkündür. Bu yazıda, kliniğimize 11 yaş 2 aylık iken, ağır solunum yetersizliği tablosu ile başvuran, yaygın iskelet displazisi bulguları olan ve Morquio Tip A tanısını geç almış olan bir hasta sunulmuştur.

Keywords

• Morquio sendromu, Tanı

Late Diagnosis of a Patient with Morquio Syndrome

Abstract

Morquio Type A Syndrome (Mucopolysaccharidosis IVA) is an autosomal recessive disorder characterized by the lysosomal accumulation of keratan sulfate and chondroitin-6 sulfate particularly in the bone and cornea due to the deficiency of N-acetylgalactosamine-6-sulfate sulfatase. The major clinical signs are short stature, skeletal dysplasia, dental anomalies, and corneal clouding. Sensorineural hearing loss, valvular heart diseases, joint laxity, and cervical myelopathy can also accompany the disease. As the affected patients do not have central nervous system involvement, the Morquio A syndrome is accepted to be a good candidate for enzyme replacement and gene therapies. Preclinical studies have shown that enzyme replacement treatment enables a significant decrease in tissue and blood keratan sulfate levels, and treatment should be performed as early as possible in lysosomal storage diseases in order to achieve successful curative therapy. In this case report, we present a patient aged 11 years and 2 months who had systemic skeletal dysplasia and was admitted to our hospital with terminal respiratory failure. Unfortunately, the patient was diagnosed as MPS IVA at the late stage of the disease and did not receive any enzyme replacement treatment

Keywords

• Morquio syndrome, Diagnosis

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