Smith-Lemli-Opitz Sendromu SLOS : Prenatal ve Postnatal Dönemde Tanısı

Öz

Smith-Lemli-Opitz Sendromu SLOS , kolesterol biyosentezindeki bir enzim eksikliğinin multipl konjenital anomalilere ve mental retardasyona yol açtığı otozomal resesif geçişli doğumsal bir metabolizma hastalığıdır. Bu çalışmada kolesterol biyosentez hastalıklarından biri olan SLOS kesin tanılı iki vakanın klinik bulguları sunulmuştur. Nedeni belirlenemeyen hafif-orta mental retardasyon ve dismorfizmi ola hastalarda, basit bir laboratuvar testi olan serum kolesterol düzeyinin düşük ya da normalin alt sınırında olması ve 7-dehidrokolesterol düzeyinde artış saptanması ile bu sendromun kesin tanısının konulabileceği vurgulanmaktadır. Taşıyıcı sıklığı ile karşılaştırıldığında kesin tanı konulan hastaların az olduğu bu sendromun tanı konma yüzdesinin arttırılabileceğini ve son yıllarda önem kazanan otistik bulguları olan hafif mental retardasyonlu SLOS vakalarının da hekimler tarafından tanınması amaçlanmaktadır.

Anahtar Kelimeler

• Smith-Lemli-Opitz Sendromu,7-dehidrokolesterol,2. ve 3. ayak parmakları sindaktilisi

Smith-Lemli-Opitz Syndrome SLOS : Prenatal and Postnatal Diagnosis

Öz

Smith-Lemli-Opitz Sendromu SLOS , is an autosomal recessive metabolic disease, caused by the deficiency of an enzyme in cholestrol biosynthesis, that has multiple congenital anomalies and mental retardation as clinical findings. Clinical findings of two patients with SLOS are discussed in this paper. Our aim is to underline the fact that a simple investigation such as serum cholestrol level being low or at the low levels of normal range that prompts the evaluation of 7- dehydrocholesterol levels, can lead to a definite diagnosis in patients with unexplained mild to moderate mental retardation, multiple congenital anomalies and facial dysmorphism. This approach will help the physicians diagnose more SLOS patients, who are being misdiagnosed or have no diagnosis at all. It will also enable more subtle cases, those with mild psychosocial motor retardation and autism, to be diagnosed.

Anahtar Kelimeler

• Smith-Lemli-Opitz Syndrome, 7-dehydrocholesterol, 2-3 toe syndactyly

Kaynakça

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