Pitt–Hopkins syndrome (PTHS, MIM #610954) is a rare neurodevelopmental disease characterized by the association of intellectual disability, characteristic facial gestalt and episodes of abnormal and irregular breathing. PTHS is due to heterozygous loss‐of‐function variants in the TCF4 gene (transcription factor 4, MIM #602272) encoding for a basic helix–loop–helix transcription factor. TCF4 is highly expressed during early development of the nervous system, and it is involved in cellular differentiation and proliferation. Since the first clinical description in 1978, less than 200 PTHS patients have been described. A comprehensive phenotype, especially regarding cancer predisposition, is not yet well defined. We report the case of a 7‐year‐old boy affected by PTHS with a 4‐week history of progressive swelling of the frontal bones diagnosed with Langerhans cell histiocytosis.

中文翻译：

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一名年轻的Pitt-Hopkins综合征患者的Langerhans细胞组织细胞增生症。

皮特-霍普金斯综合征（PTHS，MIM＃610954）是一种罕见的神经发育疾病，其特征在于智力残疾，特征性面部表情和异常和不规则呼吸的发作。PTHS是由于编码基本螺旋-环-螺旋转录因子的TCF4基因（转录因子4，MIM＃602272）中杂合性功能丧失的变异所致。TCF4在神经系统的早期发育过程中高表达，并且参与细胞分化和增殖。自1978年首次临床描述以来，已经描述了不到200名PTHS患者。尚未明确定义综合表型，尤其是关于癌症易感性的表型。我们报告了一例7岁男孩受PTHS感染的情况，该病有4周被诊断为Langerhans细胞组织细胞增生症的额骨进行性肿胀病史。