Barron Carly, Novack Shira, Prendaj Erealda, Regelmann Molly O
Division of Pediatric Endocrinology and Diabetes, Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, NY 10467, USA.
Division of Diabetes and Endocrinology, Department of Pediatrics, Cohen Children's Medical Center, New Hyde Park, NY 11042, USA.
JCEM Case Rep. 2024 Oct 23;2(11):luae190. doi: 10.1210/jcemcr/luae190. eCollection 2024 Nov.
A previously healthy 11-month-old, full-term female developed growth failure, feeding intolerance, and irritability starting at 10 months of age. She was found to have a serum calcium level of 3.75 mmol/L (15 mg/dL) (reference range, 2.13-2.62 mmol/L; 8.5-10.5 mg/dL), consistent with severe hypercalcemia. She had bilateral nephrocalcinosis. Hypercalcemia improved with intravenous fluid hydration, but calcium rose again once intravenous fluids were discontinued and while consuming a low-calcium diet. Laboratory tests for common causes of hypercalcemia were negative. Stool-reducing substances were positive on 2 occasions. Endoscopic biopsy confirmed low disaccharidase levels. Her diet was changed to disaccharide-free formula, and hypercalcemia resolved. Genetic testing for congenital disaccharidase deficiency was negative. After repeat endoscopy demonstrating improved disaccharidase levels, disaccharides were incrementally reintroduced to the diet and calcium levels remained normal. This case demonstrates that disaccharidase deficiency, a rare inborn error of metabolism associated with hypercalcemia, may be a transient cause of hypercalcemia. The mechanism of hypercalcemia remains unknown.
一名此前健康的11个月大足月女婴，从10个月大开始出现生长发育迟缓、喂养不耐受和易激惹。她的血清钙水平为3.75 mmol/L（15 mg/dL）（参考范围为2.13 - 2.62 mmol/L；8.5 - 10.5 mg/dL），符合严重高钙血症。她有双侧肾钙质沉着症。通过静脉补液，高钙血症有所改善，但一旦停止静脉补液并采用低钙饮食，钙水平又再次升高。针对高钙血症常见病因的实验室检查均为阴性。粪便还原物质检测有两次呈阳性。内镜活检证实双糖酶水平较低。她的饮食改为不含双糖的配方奶，高钙血症得以缓解。先天性双糖酶缺乏症的基因检测结果为阴性。在重复内镜检查显示双糖酶水平有所改善后，双糖逐渐重新引入饮食中，钙水平仍保持正常。该病例表明，双糖酶缺乏症这种与高钙血症相关的罕见先天性代谢缺陷，可能是高钙血症的一个短暂病因。高钙血症的机制尚不清楚。
