7673 Genetic Analysis and Clinical Characterization of Patients with Congenital Hypopituitarism Due to Gene Defects

Abstract

Abstract Disclosure: T.M. Sasson: None. I.J. Arnhold: None. B.B. Mendonca: None. L.R. Carvalho: None. Introduction: Congenital hypopituitarism is characterized by the deficiency of one or more hormones secreted by the anterior pituitary gland. The genetics of this pathology is complex, and the molecular diagnosis is established in approximately 13% of cases. Objectives: The aim of the present study is to characterize the phenotype harboring pathogenic variants causing congenital hypopituitarism. Methods: Among 393 subjects with congenital hypopituitarism followed up at a tertiary health center, 57 subjects (14,5%) were selected due to a confirmed molecular diagnosis by exome in 9 subjects or by gene panel or Sanger sequencing in 48 subjects. This was a retrospective study where data from medical records, clinical, laboratory and radiological characteristics were analyzed. Results: The most frequent variants identified by sequencing analyzes were in the following genes: PROP1 (29.8%), GH1 (22.8%), GHRHR (15.7%), followed by GLI2, OTX2, HESX1, POU1F1, TGIF1, GHRS, CDH2, SATB1, SOX3 e LZTR1. Consanguinity was reported in 50% of cases, and there was the presence of familial cases of short stature in 60%. The average age at the start of follow-up was 11.1 years (11 SD), 40% of them were male and 52.3% had physical stigmata typical of GH deficiency. Regarding hormonal deficiencies, 27 (47%) had isolated Growth Hormone Deficiency (DGHI) and the others, multiple deficiencies. MRI study of the pituitary gland showed some alteration in 66%, 54% of whom had adenohypophysis hypoplasia and 31% had an ectopic or non-visualized neurohypophysis. From 29 patients with IGF-1 levels available, 28 were below the reference range for sex and age. The serum GH peak after the stimulus test was on average 1.28 ng/mL (1.4SD), of these, only 4 cases had GH peak between 3.3 and 5.0 ng/mL and 1 patient with low IGF-1 and an ectopic neurohypophysis had GH peak of 6.0 ng/mL in a glucagon test. Regarding growth, the initial height in z-score was -4.8 and the average growth at the end of the first year of treatment was 10.7cm, with the average height after this period of Z-3.35. The average of final delta target height (final height Z-score minus the target height Z-score) of patients who underwent hormonal treatment was -0,53 (good response = delta <-1.5). Conclusion: In subjects with congenital hypopituitarism and an established molecular diagnosis, the most frequently affected genes were PROP1 and GH1, the great majority presented a stimulated GH peak < 3.3 ng/mL (only one patient had GH > 5), low basal serum IGF-1 and good increase in growth speed at the end of the first year of treatment with recovery of final height at the end of GH therapy. Presentation: 6/3/2024