Growth hormone deficiency in a child with benign hereditary chorea caused by a de novo mutation of the TITF1/NKX2-1 gene

Objectives Benign Hereditary Chorea (BHC) (MIM 118700) is a rare childhood-onset movements disorder characterized by non-progressive chorea. It is usually caused by variants in the thyroid transcription factor 1 (TITF-1/NKX2-1) gene and it is associated with thyroid dysfunction and pulmonary symptoms in the brain–lung–thyroid syndrome. Case presentation We reported the clinical case of a toddler presenting with neurological symptoms (hypotonia, delayed motor milestones, and axial dystonia) and subclinical hypothyroidism in which we found a ‘de novo’ variant in the NKX2-1 gene. Conclusions The peculiarity of our case is that the mild alteration of thyroid-stimulating hormone (TSH) levels, hypotonia, and delayed motor milestones were associated with growth hormone deficiency.

A Not So Benign Family Pedigree With Hereditary Chorea: A Broader Phenotypic Expression or Additional Picture?

NKX2-1 mutations have been usually associated with a non-progressive neurological disease. Recent reports revealed a vast variability regarding its clinical expressivity. Aim of this work was widening the Benign Hereditary Chorea neurological, cognitive and behavioral phenotype through the description of a child and her family pedigree. Molecular analysis focused on NKX2-1 gene revealed a novel frameshift mutation in the three-generation members described. Cognitive scales detected a relevant developmental delay, and the clinical observation and Autism Diagnostic Observation Schedule -2 administration allowed the diagnosis of autism spectrum disorder in the proband. Microarray testing, further executed to exclude a double hit contextually provoking the complex neurodevelopmental disorder, revealed the 22q11.2 Duplication Syndrome. This paper may contribute to enlarge Benign Hereditary Chorea variable expressivity and, together with other studies reported in the literature, underlines the need to reconsider the term “benign,” verifying the opportunity of more a complex diagnosis.