KCNJ2 gene spontaneous missense mutation in a child with Andersen-Tawil syndrome: a case report
- 1Department of Endocrinology and Metabolism, Shandong Medical and Pharmaceutical University Hospital, Shandong Medical and Pharmaceutical University, Binzhou, Shandong, China
Abstract
Background: Andersen-Tawil syndrome (ATS) is a rare disorder featuring ventricular arrhythmias, periodic paralysis, and skeletal anomalies. KCNJ2 mutations account for about 70% of cases. We report a child with a novel KCNJ2 mutation and subclinical hypothyroidism, an association not previously described.
Case presentation: A 10-year-old boy presented with episodic limb weakness, palpitations, low-set ears, and bilateral fifth-finger bending. Labs showed spontaneous normokalemia without potassium supplementation, elevated creatine kinase, and subclinical hypothyroidism. ECG revealed frequent ventricular premature beats. Genetic testing identified a heterozygous KCNJ2 c.461G > A (p.C154Y) mutation, confirmed as de novo.
Results: The patient was treated with propafenone and acetazolamide. At six months, paralytic episodes decreased from weekly to one mild event, and premature beats reduced markedly on Holter. No adverse effects occurred.
Conclusion: This case expands the KCNJ2 mutation spectrum and suggests thyroid screening may be considered in ATS. With proper treatment, short-term prognosis is favorable.
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BibTeX
@article{feng2026kcnj2,
title = {{KCNJ2 gene spontaneous missense mutation in a child with Andersen-Tawil syndrome: a case report}},
author = {Meiqi Feng and Xi Wang and Lingshan Hu and Lei Zhang},
journal = {Frontiers in Pediatrics},
year = {2026},
month = oct,
doi = {10.3389/fped.2026.1961456},
url = {https://doi.org/10.3389/fped.2026.1961456},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - KCNJ2 gene spontaneous missense mutation in a child with Andersen-Tawil syndrome: a case report
AU - Meiqi Feng
AU - Xi Wang
AU - Lingshan Hu
AU - Lei Zhang
PY - 2026
DA - 2026/10/12
JO - Frontiers in Pediatrics
DO - 10.3389/fped.2026.1961456
UR - https://doi.org/10.3389/fped.2026.1961456
AB - Background: Andersen-Tawil syndrome (ATS) is a rare disorder featuring ventricular arrhythmias, periodic paralysis, and skeletal anomalies. KCNJ2 mutations account for about 70% of cases. We report a child with a novel KCNJ2 mutation and subclinical hypothyroidism, an association not previously described. Case presentation: A 10-year-old boy presented with episodic limb weakness, palpitations, low-set ears, and bilateral fifth-finger bending. Labs showed spontaneous normokalemia without potassium supplementation, elevated creatine kinase, and subclinical hypothyroidism. ECG revealed frequent ventricular premature beats. Genetic testing identified a heterozygous KCNJ2 c.461G > A (p.C154Y) mutation, confirmed as de novo. Results: The patient was treated with propafenone and acetazolamide. At six months, paralytic episodes decreased from weekly to one mild event, and premature beats reduced markedly on Holter. No adverse effects occurred. Conclusion: This case expands the KCNJ2 mutation spectrum and suggests thyroid screening may be considered in ATS. With proper treatment, short-term prognosis is favorable.
SN - 2296-2360
ER -