Syndrome of inappropriate secretion of anti-diuretic hormone due to hypothalamic hamartoma: use of tolvaptan

• Published in: Journal of pediatric endocrinology & metabolism : JPEM Vol. 36; no. 9; pp. 895 - 899
• Main Authors: Moon, Rebecca Jane, Soliman, Maisara, Hoogenboom, Lieke, Gilbert, Rodney D, Bird-Lieberman, Georgina, Singh, Jaspal, Bockenhauer, Detlef, Kumaran, Anitha
• Format: Report
• Language: English
• Published: 26.09.2023
• ISSN: 2191-0251
• DOI: 10.1515/jpem-2023-0136

OBJECTIVESHypothalamic hamartoma (HH) typically presents with gonadotrophin-dependent precocious puberty and/or seizures. Other endocrine disturbances are rare. We describe an infant with syndrome of inappropriate secretion of anti-diuretic hormone (SIADH) and a HH. CASE PRESENTATIONA 6-week-old infant presented with seizures and life-threatening hyponatremia. A HH was identified on magnetic resonance imaging. Clinical examination and biochemistry were consistent with SIADH, and serum copeptin was high during hyponatremia, further supporting this diagnosis. Tolvaptan was effective in normalizing plasma sodium and enabling liberalization of fluids to ensure sufficient nutritional intake and weight gain and manage hunger. CONCLUSIONSHyponatremia due to SIADH is novel at presentation of a HH, and can be challenging to diagnose and manage. Successful management of hyponatremia in this case was achieved using tolvaptan.