A Rare Presentation of HIST1H1E Syndrome with Short Stature and Multiple Pituitary Hormone Deficiencies

Histone Gene Cluster 1 Member E (HIST1H1E) syndrome is a rare autosomal dominant disorder resulting from a heterozygous variation in the H1-4 gene located on chromosome 6p22.2. Mental retardation, recognizable facial features, skeletal abnormalities and overgrowth are the main clinical manifestations of this syndrome. A 17-year-old male presented to the pediatric endocrinology clinic due to short stature. He had a characteristic facial appearance with neurodevelopmental delay. Genetic analysis revealed a heterozygous pathogenic variation in the H1-4 gene located on chromosome 6p22.2 which confirmed his diagnosis of HIST1H1E syndrome. This presentation was distinguished by the co-occurrence of short stature and obesity accompanying central hypothyroidism and growth hormone deficiency due to a hypoplastic pituitary gland, which is in marked contrast to the somatic overgrowth characterizing this syndrome. Furthermore, the presented case is the second patient reported with HIST1H1E syndrome with hyposecretion of multiple pituitary hormones caused by hypoplasia of the pituitary gland.