[Analysis of a neonate with Hypoparathyroidism-sensorineural deafness-renal dysplasia syndrome and a literature review].

Objective: To analyze the phenotype and genotype of a neonate with Hypoparathyroidism-sensorineural deafness-renal dysplasia syndrome (HDR).

Methods: A female neonate with HDR syndrome and thyroid deficiency detected at the First Affiliated Hospital of Zhengzhou University on December 6,2023 was selected as the study subject, Low-coverage whole-genome sequencing (Lc WGS) and whole exome sequencing (WES) were carried out. Using "hypoparathyroidism""sensorineural deafness""renal dysplasia""HDR""Barakat" and"GATA3" as keywords, the CNKI, Wanfang Data Knowledge Service Platform and PubMed database were searched, and the retrieval time was set from the establishment to March 2025.

Results: A proband, a full-term female infant, had presented with feeding difficulty, micrognathia, and low-set ears. Serological test revealed hypocalcemia, hyperphosphatemia, hypoparathyroidism, low T3, low T4 and high TSH. Hearing test revealed bilateral sensorineural deafness. Ultrasonic test revealed absence of right kidney and thyroid. WES revealed that the she has harbored a deletion of approximately 6.67 Mb at 10p15.1p13, and Lc WGS confirmed the presence of a 6.70 Mb deletion in the same region, which was verified as a de novo variant. Literature review suggested that HDR was rarely diagnosed among neonates. Among the nine cases diagnosed in neonatal period, 66.6% (6/9) exhibited the typical triad, 77.7% (7/9) had hypoparathyroidism with hypocalcemic convulsion as the initial symptom, 22.2% (2/9) had sensorineural hearing loss or renal malformation, and 66.6% (6/9) had multiple malformations including facial dysmorphism and congenital heart disease. 55.5% (5/9) had a large deletion in the 10p15 region, whilst 33.3% (3/9) had a single gene variant. The range of the deletion had correlated with the diversity of clinical phenotypes in HDR syndrome, but the classic triad of symptoms may presented in any combination, independent of deletion size. Association of HDR with thyroid deficiency has been unreported previously.

Conclusion: For neonates presenting with one of the symptoms of HDR triad or in combination with other malformations, genetic testing should be carried out.