The Pitt-Hopkins Syndrome: Report of 5 Patients and Literature Comparison

Year 2021, Volume: 5 Issue: 3, 317 - 325, 31.12.2021

Gültekin Kutluk , Elif Naz Kadem , Nadide Cemre Randa , Ayşe Öz

https://doi.org/10.30565/medalanya.891840

Cited By: 2

Abstract

Pitt-Hopkins syndrome (PTHS) is characterized by developmental delay, intellectual disability and behavioral changes, distinctive facial gestalt, and breathing abnormalities. PTHS is caused by deletions or pathological variants in the TCF4 gene located at 18q21.2. In this report, we aimed to describe the clinical and genetic findings of patients diagnosed with PTHS and compare our patients with the literature. Patients who were followed up with severe intellectual disability and a variable association of features previously described as characteristic of the PTHS phenotype in the pediatric neurology clinic of Antalya Training and Research Hospital were screened for TCF4 mutations using next-generation sequencing (NGS)-based tests, between 2017 and 2020. A genetic mutation associated with PTHS was detected in five patients. This paper emphasis on mutational and clinical spectrum of PTHS and its significant part in the differential diagnosis of severe mental retardation

Keywords

Angelman syndrome, breath-holding episode, intellectual disability, Pitt-Hopkins syndrome, TCF4

Pitt-Hopkins Sendromu: 5 Vaka Sunumu ve Literatür Karşılaştırması

Abstract

Pitt-Hopkins sendromu (PTHS) gelişimsel gecikme, mental retardasyon ve davranış değişiklikleri, belirgin yüz görünümü ve solunum anormallikleri ile karakterizedir. PTHS, 18q21.2'de bulunan TCF4 genindeki delesyonlardan veya varyantlardan kaynaklanır. Bu yazıda PTHS tanısı alan hastaların klinik ve genetik bulgularını tanımlamayı ve bulgularımızı literatür ile karşılaştırmayı amaçladık. Antalya Eğitim ve Araştırma Hastanesi pediatrik nöroloji kliniğinde 2017 ve 2020 arasında takip edilen, ağır mental retardasyon ve daha önce PTHS fenotipinin karakteristiği olarak tanımlanan özellikleri taşıyan hastalar, yeni nesil dizileme (NGS) tabanlı testler ile TCF4 mutasyonları açısından tarandı. 5 hastada PTHS ile ilişkili bir genetik mutasyon tespit edildi. Bu yazıda, PTHS'nin mutasyonel ve klinik spektrumuna ve ciddi zihinsel geriliğin ayırıcı tanısındaki önemli kısmına vurgulandı.

Keywords

Angelman sendromu, nefes tutma nöbetleri, Pitt-hopkins sendromu, TCF4, zeka geriliği

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