Salvado Maria, Boronat-Guerrero Susanna, Hernández-Vara Jorge, Álvarez-Sabin José
Servicio de Neurología, VHIR, Hospital Universitari Vall d'Hebron, E-08035 Barcelona, Espana.
Rev Neurol. 2013 May 16;56(10):515-20.
Chorea due to a mutation in the TITF1 gene, which is also known as benign hereditary chorea, is an autosomal dominant disorder that usually begins before the age of 5 years. In most cases, the chorea tends to improve as the child gets older. It may be associated to hypothyroidism and respiratory problems, such as neonatal alveolar respiratory distress syndrome or interstitial disease, since TITF1 is a transcription factor that is essential for the development of the brain, thyroid gland and lung.
We report on the clinical phenotype of a family with chorea, in which two sisters presented congenital hypothyroidism and one of them also had alveolar respiratory distress syndrome. A mutation was detected in TITF1 (c.825delC) in both of them and clinical improvement was observed in the response to treatment with low doses of levodopa-carbidopa.
Chorea due to mutation of TITF1 is an underdiagnosed cause of chorea in children. Since it is possible to conduct a genetic diagnosis, we believe that performing it is always indicated in dominant familial cases, bearing in mind the variable penetrance, as well as in patients who present concomitant involvement of the lungs or hypothyroidism. Occasionally, it may be recommendable in cases of chorea with an unknown causation, which will enable us to avoid other tests, give a non-degenerative prognosis, offer genetic counselling and carry out more guided and effective therapeutic trials. For the time being, levodopa seems to be the preferred symptomatic treatment.
由TITF1基因（也称为良性遗传性舞蹈症）突变引起的舞蹈症是一种常染色体显性疾病，通常在5岁前发病。在大多数情况下，随着孩子年龄增长，舞蹈症症状往往会改善。它可能与甲状腺功能减退及呼吸问题相关，如新生儿肺泡呼吸窘迫综合征或间质性疾病，因为TITF1是一种对脑、甲状腺和肺发育至关重要的转录因子。
我们报告了一个患有舞蹈症的家族的临床表型，其中两姐妹患有先天性甲状腺功能减退，其中一人还患有肺泡呼吸窘迫综合征。在她们两人中均检测到TITF1基因的一个突变（c.825delC），并且观察到低剂量左旋多巴 - 卡比多巴治疗后临床症状有所改善。
由TITF1基因突变引起的舞蹈症是儿童舞蹈症中一种未被充分诊断的病因。由于可以进行基因诊断，我们认为在显性家族性病例中，鉴于其可变的外显率，以及在伴有肺部受累或甲状腺功能减退的患者中，进行基因诊断总是必要的。偶尔，在病因不明的舞蹈症病例中也可能值得推荐，这将使我们能够避免其他检查，给出非退行性的预后判断，提供遗传咨询并开展更具针对性和有效性的治疗试验。目前，左旋多巴似乎是首选的对症治疗药物。
