Background: Hypocalcemia is an electrolyte disorder that can be effectively corrected. However, in its severe form, it poses significant risks, including potentially fatal symptoms such as electrocardiographic changes that may lead to sudden cardiac arrest if not treated promptly.

Case presentation: We report the case of a young female patient who presented with multiple episodes of tonic posturing and altered level of consciousness. Diagnostic evaluation revealed severe hypocalcemia with hypomagnesemia, QT prolongation, and episodes of non-sustained ventricular tachycardia. The condition was managed with calcium and magnesium supplementation. Further investigations revealed a novel missense mutation in transient receptor potential melastatin 3 (TRPM3).

Discussion: Hypocalcemic seizures are rare in adults and are typically associated with severe hypocalcemia and cardiovascular instability, including ventricular dysrhythmias. The differential diagnoses in this case included primary hypoparathyroidism, Bartter syndrome type 5 (CaSR (calcium-sensing receptor) mutation), Gitelman syndrome, and claudin mutations. TRPM3 is highly expressed in kidney tissue, playing a role in the resorption of calcium and divalent ions. However, further research is needed to confirm its role in calcium homeostasis.

Conclusion: The patient was initially misdiagnosed with epilepsy for the past two years. Following a comprehensive evaluation, she was successfully treated with intravenous calcium and magnesium. On follow-up after six months, her condition showed marked improvement, characterized by better cardiac function and the absence of further seizure episodes. This case represents the first reported instance of a TRPM3 mutation affecting calcium channels, highlighting the need for further investigation into its implications for calcium metabolism.

Keywords: Hypocalcemia; TRPM3; cardiomyopathy; seizure; ventricular tachycardia.

© 2025 Bhellum, Angirekula, Rohila, Sharma, Gupta, Mathur, licensee HBKU Press. This is an open access article distributed under the terms of the Creative Commons Attribution license CC BY 4.0, which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited.

背景：

低钙血症是一种可以通过有效补充电解质来纠正的电解质紊乱。然而，在其严重形式下，它会带来显著的风险，包括可能导致突然心脏骤停等潜在致命症状（如心电图变化），如果不能及时治疗的话。

病例介绍：

我们报道了一位年轻女性患者的情况，她因多次出现阵挛性姿势和意识水平改变而就诊。诊断评估发现严重的低钙血症、低镁血症、QT间期延长以及非持续性室速发作。病情通过补钙和补镁治疗得以管理。进一步的检查揭示了瞬态受体电位通道蛋白3 (TRPM3) 中的一个新的错义突变。

讨论：

低钙血症引起的癫痫在成年人中较为罕见，通常与严重的低钙血症和心血管不稳定相关，包括室性心律失常。本病例中的鉴别诊断包括原发性甲状旁腺功能减退、巴特氏综合征5型（CaSR突变）、Gitelman 综合征以及 claudin 突变。TRPM3 在肾组织中高度表达，在钙和二价离子的重吸收中起重要作用，但需要进一步研究来确认其在钙稳态中的作用。

结论：

该患者此前两年一直被误诊为癫痫。经过全面评估后，她接受了静脉补钙和补镁治疗并成功恢复。六个月后的随访显示病情显著改善，表现为心脏功能更好且没有再出现抽搐发作。本案例首次报道了TRPM3突变影响钙通道的情况，强调了对其对钙代谢的影响进行进一步研究的必要性。

关键词：

低钙血症；TRPM3；心肌病；癫痫；室速。

© 2025 Bhellum, Angirekula, Rohila, Sharma, Gupta, Mathur, licensee HBKU Press. This is an open access article distributed under the terms of the Creative Commons Attribution license CC BY 4.0, which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited.