One Syndrome, Different Phenotypes: Fragile X Syndrome

Öz

Aim: The main findings in fragile X syndrome are varying degrees of mental retardation, a long, narrow face, a prominent forehead and chin, and large ears. The purpose of this study was to evaluate patient and family histories, clinical characteristics, laboratory findings, and close clinical follow-up of cases diagnosed with fragile X syndrome.

Material and Method: Clinical and physical examination characteristics and laboratory results of cases diagnosed with fragile X syndrome were evaluated retrospectively.

Results: Five male patients aged 5-14 years were included in the study. Varying degrees of mental retardation and a coarse facial appearance were present in all cases. The most common presentation symptom in our polyclinic was mental retardation. Hyperactivity was present in two patients, self-harm behavior in one, and forgetfulness and enuresis in one. Neuromotor retardation was present in all patients, who were therefore receiving special education, while atypical autism was diagnosed in one case and a history of drug use due to ADHD was present in another. Metabolic, blood count, and biochemical parameters were with normal ranges. Cranial imaging was normal in two patients, while a moderate increase in subarachnoid space in the bilateral hippocampal areas was observed in Case 1, hypoplasia in the splenium and the posterior 1/3 of the body of the corpus callosum in Case 3, and hyperintensity on T2A/FLAIR in the posterior periventricular area in Case 4. No problems were encountered during 6-9-month follow-up. Two brothers of one case were also referred for special education following genetic counseling provided for the families. 

Conclusion: Increasing numbers of patients with undiagnosed mental retardation are presenting to pediatric general and side branch polyclinics. Fragile x syndrome is the first condition that should be considered in patients with a long/narrow face, a prominent forehead/jaw, large ears, macroorchidism, and mental retardation.

Anahtar Kelimeler

• childhood,Fragile X syndrome,mental retardation

Bir Sendrom, Farklı Fenotipler; Fragile X Sendromu

Öz

Amaç: Fragile-X sendromunda değişen derecelerde zihinsel gerilik, uzun ve dar yüz, öne çıkan alın ve çene yapısı, büyük kulaklar temel bulgulardır. Bu çalışmada Fragile X sendromu tanısı konulan olguların özgeçmiş-soygeçmiş, klinik özellikleri, laboratuvar bulguları ve yakın klinik izlemlerinin değerlendirilmesi amaçlanmıştır.

Gereç ve Yöntem: Fragile X sendromu tanısı koyulan olguların klinik ve fizik muayene özellikleri, laboratuvar sonuçları retrospektif olarak değerlendirildi.

Bulgular: Yaşları 5-14 yaş arasında değişen 5 erkek olgu çalışmaya dahil edildi. Olguların tamamında değişen derecelerde mental retardasyon ve kaba yüz görünümü mevcuttu. Hastalarımızın polikliniğe en sık başvuru yakınması zihinsel gerilikti. İki hastada hiperaktivite, bir hastada kendine zarar verme, bir hastada unutkanlık ve enürezis mevcuttu. Çalışmaya dahil edilen olguların tamamında nöromotor retardasyon olduğu ve bu nedenle özel eğitim aldığı, bir olgunun atipik otizm tanısı olduğu, bir hastanın ise DEHAB nedeni ile ilaç kulanım öyküsü olduğu belirlendi. Metabolik, hemogram ve biokimyasal parametreler normal aralıktaydı. İki hastanın kranial görüntülemesi normaldi, diğer hastaların kranial görüntülemesinde; Olgu 1’de bilateral hipokampal alanda subraknoid mesafede ılımlı artış, Olgu 3’te korpus kallosum gövde 1/3 arka kısım ve spleniumda hipoplazi, Olgu 4’te periventrikuler posterior alanda T2A/FLAIR’de hiperintensite izlendi. Olguların 6-9 aylık izleminde herhangi bir sorunla karşılaşılmadı. Ailelere verilen genetik danışmanlık sonrasında bir olgunun iki erkek kardeşinde de Fragile X sendromu tanısı konularak özel eğitime yönlendirildi. 

Sonuçlar: Genel pediatri polikliniği ve çocuk yan dal polikliniklerine her gün çok sayıda tanısı konulamayan mental retarde hasta başvurmaktadır. Uzun/dar yüz, öne çıkan alın/çene yapısı, büyük kulaklar, makroorşidizm ve zihinsel geriliği olan hastalarda ilk düşünmemiz gereken Fragile X sendromudur

Anahtar Kelimeler

• çocukluk çağı,Fragile X sendromu,zihinsel gerilik

Kaynakça

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