Mucopolysaccharidosis type 4 (Morquio syndrome): a case report

Objective: Mucopolysaccharidoses, develop with genetic transmission which cause destructive changes in various organs as a result of glycasoaminoglycans deposition in lysosomes. Herein, we are presenting a case with Morquio syndrome so as to attract attention to this rarely seen disease.
Case: A 11-year-old male patient presented to our hospital with complaints of short stature, andbone deformities. The parents were not relatives, and he had 3 healthy younger siblings. On physicalexamination, coarse facial features, hypertelorism, disproportionate short stature, genu valgum, pectus carinatum, kyphoscoliosis, were detected. He demonstrated a waddling gait. His neuromotor development was normal for his age. On bone radiograms, kyphoscoliosis, flared iliac wings, coxa valga, flattening of femoral epiphysis, widened ribs, and narrowed iliac wings were detected. Urine tests were positive for glycosaminoglycans (keratan sulphate). Enzymatic analysis revealed low levels of glucose-6-phosphatase [15 pmol/mg/hr, (n: 400-2000)], which made the final diagnosis.
Conclusions: Morquio syndrome has Aand B types with similar clinical manifestations which are transmitted as an autosomal recessive trait. Tip 4A is a disease due to a deficiency of galactosamine6-sulfatase (GALNS) enzyme, which is encoded by the 16q24.3 gene, while Type 4B is characterized by deficiency of beta galactosidase. In both types of the disease, keratan sulphate, and chondrotin
6 sulphate accumulate. Also in our case manifestations became more prominent around age 1, and gradually progressed. Our patient without mental problems had typical skeletal signs on radiograms which is named dysostosis multiplex. It is necessary to initiate enzyme replacement therapybefore the onset of gait disorders.

Bir olgu nedeni ile mukopolisakkaridoz tip 4 (Morquio sendromu)

Amaç: Mukopolisakkaridozlar, genetik geçiþli ve lizozomlarda glikozamino glikan depolanmasý sonucu vücuttaki çeþitli organlarda hasara yol açan hastalýklardýr. Burada nadir görülen bir tür olan Morquio sendromlu bu olguyu konuya dikkat çekmek amacý ile sunmaktayýz.
Olgu: Onbir yaþýndaki erkek hasta, hastanemize boy kýsalýðý ve kemik bozukluklarý nedeni ile baþvurdu. Anne baba akraba deðildi ve olgumuzun üç saðlýklý küçük kardeþi vardý. Fizik muayenede kaba yüz, hipertelorizm, orantýsýz boy kýsalýðý, çarpýk bacak, pektus karinatum, kifoskolyoz saptandý. Ördekvari yürüyüþü vardý. Nöromotor geliþimi yaþýna uygundu. Kemik grafilerinde kifoskolyoz, iliak kanatlarda parlama, koksa valga, femoral epifizlerde düzleþme, geniþlemiþ kaburga kemikleri ve dar iliak kanatlar tespit edildi. Ýdrarda glikozaminoglikan (keratan sülfat) pozitif bulundu. Enzimatik analizde glukoz-6- fosfataz düþük bulunarak [15 pmol/mg/saat (n: 400-2000)] kesin taný kondu.
Sonuçlar: Morquio sendromunun benzer klinik tablolarý olan ve otozomal resesif kalýtýlan A ve B tipleri vardýr. Tip 4A galactosamine-6-sulfatase (GALNS) enzim eksikliðine baðlý 16q24.3 geni ile kodlanan hastalýk iken, Tip 4B beta galaktozidaz eksikliði ile ortaya çýkar. Her iki tip hastalýkta da, keratan sülfat ve kondrotin 6 sülfat birikmektedir. Bizim olgumuzda da bulgular 1 yaþ civarýnda belirginleþmiþ ve giderek ilerlemiþtir. Zeka problemi olmayan hastamýzýn, dizostozis multipleks olarak adlandýrýlan kemik radyolojik bulgularý tipiktir. Enzim replasman tedavisinin yürüme fonksiyonunu kaybetmeden baþlanmasý önemlidir.