ESPE Abstracts

The pituitary gland is a pea-sized organ located at the base of the brain. It synthesizes, and secretes, many hormones that control growth and development, and the functioning of the other endocrine glands. Panhypopituitarism is a condition of inadequate or absent production of all these hormones. LHX3 (LIM Homeobox 3) is a Protein-Coding gene involved in pituitary development. Mutations in this gene may result in a deficiency of multiple pituitary hormones. Here, we present an Iranian female infant with a homozygote mutation in LHX3 gene who was born from distant relative parents. Hypoglycemia and seizure were the first manifestations of the disease in our patient that appeared at the age of two months. At this time, short stature was noticed; both height and weight were below 3rd percentile for age. The patient's clinical history revealed signs of hypopituitarism, so with regard to the probable this diagnosis, more screening was performed. Laboratory tests were sent. The results of complete testing showed deficiency of GH, TSH, ft4, ACTH, and later cortisol hormones. With notice to these finding and associated defects such as short stature, short neck, macroglossia and face hoarseness, Panhypopituitarism was revealed. Therefore, the replacement therapy initiated as soon as possible with Levothyroxine, Hydrocortisone and growth hormone at 2 months old, shortly afterwards blood sugar normalized and she achieved remarkable improvement in height and weight within the first months of hormone replacement therapy

Results: In order to identify the genetic cause of this problem, Whole Exome Sequencing (WES) was performed for this patient. Molecular study revealed a homozygous likely pathogenic variant in exon 5 of the LHX3 gene (c.625C>T; p. Arg209Trp). This mutation leads to complete inactive LHX3 proteins.

Conclusions: Panhypopituitarism in infants is rare, but has life- threatening complications if untreated; this report describes the novel LHX3 mutations and highlights the importance of molecular study diagnosis in patients with congenital MPHD for making definite diagnosis and treatment