Published online Sep 16, 2023. doi: 10.12998/wjcc.v11.i26.6262
Peer-review started: June 6, 2023
First decision: July 28, 2023
Revised: July 31, 2023
Accepted: August 15, 2023
Article in press: August 15, 2023
Published online: September 16, 2023
Processing time: 93 Days and 23.7 Hours
Holoprosencephaly (HPE) is a congenital malformation with various degrees of incomplete separation of the cerebral hemispheres due to differentiation disorders of the forebrain. Although HPE with diabetes insipidus due to associated pituitary dysfunction has been reported, HPE with the syndrome of inappropriate antidiuretic hormone secretion (SIADH) is very rare. Tolvaptan, a vasopressin V2 receptor antagonist, is effective in adults with SIADH. However, there is no report of its efficacy in infants with SIADH. The purpose of this report is to demonstrate that tolvaptan is effective for SIADH in infants and that administration of tolvaptan eliminates the need for restriction of water intake and sodium administration.
A 2414-g female infant was born at 38 wk by normal vaginal delivery. Facial anomalies and head magnetic resonance imaging indicated semilobar HPE. After birth, she had hyponatremia due to SIADH and was treated using water and sodium restriction. However, she developed an exaggerated response to the fluid restrictions, resulting in large fluctuations in serum sodium levels. Subsequent administration of tolvaptan improved the fluctuations in serum sodium levels without the need for adjustment of water or sodium administration. Serum sodium was maintained within the normal range after discontinuation of tolvaptan at 80 d of life. There were no side effects, such as hypernatremia or liver dysfunction, during the administration of tolvaptan.
This is the first report on the safety and efficacy of tolvaptan in an infant with SIADH associated with HPE.
Core Tip: Holoprosencephaly with the syndrome of inappropriate antidiuretic hormone secretion (SIADH) is very rare. The main treatments for SIADH are restriction of water intake and sodium administration, which could inhibit the infant’s growth. Tolvaptan, a vasopressin V2 receptor antagonist, is effective in adults with SIADH but has not been reported in infants. In the present neonatal case, the patient developed SIADH, and a restriction of water intake and sodium administration caused the fluctuations in serum sodium levels. Subsequent administration of tolvaptan improved the serum sodium level. Tolvaptan could be a novel standard treatment for infants with SIADH.