Charfi Hajer, Bertholet-Thomas Aurelia, Bacchetta Justine, Flammier Sacha, Dubourg Laurence Derain, De Mul Aurélie
Centre de Référence Des Maladies Rénales Rares, Centre de Référence Des Maladies Rares du Calcium Et du Phosphore, Filières Maladies Rares ORKiD, OSCAR Et ERKNet, Hôpital Femme Mère Enfant, 69677, Bron, France.
INSERM UMR 1033 LYOS, 69008, Lyon, France.
Eur J Pediatr. 2025 Sep 12;184(10):613. doi: 10.1007/s00431-025-06394-0.
Growth faltering and/or failure to thrive in children often prompts metabolic assessment, sometimes revealing metabolic acidosis and leading to referral to pediatric nephrology. Renal tubular acidosis (RTA), causing hyperchloremic metabolic acidosis due to impaired renal acidification, includes transient isolated RTA, a relatively frequent but poorly described condition. We reviewed pediatric patients referred to the Lyon Rare Kidney Disease Center (MAREGE) between March 2023 and March 2024 for linear growth faltering and/or failure to thrive associated with isolated metabolic acidosis, after excluding systemic, endocrine, and gastrointestinal causes. Patients with suspected secondary, genetic forms, or distal RTA were excluded. Follow-up was analyzed from the initial nephrology consultation to the last visit before March 2025. Data are presented as medians [IQR] and compared using non-parametric tests. Thirty-five patients were included. At diagnosis, age was 15.3 [13.1-25.6] months, with weight and height standard deviation (SD) scores of - 1.5 [- 2.5; - 1.0] and - 1.0 [- 2.0; 0.0], respectively. Tubular assessments showed low plasma bicarbonate (19 [18-20] mmol/L), non-adapted bicarbonaturia (8.0 [2.8-18.6] mmol/L), and elevated urinary pH (7.0 [6.4-7.4]). After a follow-up of 2.2 [1.4-3.1] years at an of age 3.4 [1.9-4.1] years, weight SD scores increased significantly (- 1.0 [- 1.9; - 0.4], p = 0.04). Height SD scores also increased (- 0.5 [- 1.5; 0.0]), though not significantly (p = 0.41). Catch-up growth in weight, height, or both was achieved in 77% of patients. Bicarbonate supplementation, initiated at 1.2 [0.7-1.6] mmol/kg/day, was discontinued in 54% of cases; for others, dosing remained stable (1.3 [0.9-2.0] mmol/kg/day, p = 0.16).
Transient isolated RTA is observed in infants and young children with mild metabolic acidosis, isolated bicarbonaturia, and moderate failure to thrive and/or growth faltering. It resolves spontaneously within a few years, usually requiring only low-dose alkalizing therapy.
• Renal tubular acidosis (RTA) is a hyperchloremic, normal anion gap metabolic acidosis due to impaired renal acidification. In children, it is a recognized cause of growth faltering or failure to thrive and is usually a genetic disease (either proximal or distal acidosis).
• In cases of mild metabolic acidosis associated with moderate growth delay, without other tubular or extrarenal abnormalities, the possibility of transient isolated renal tubular acidosis should be considered. This condition warrants parental reassurance, as most patients show catch-up growth with minimal bicarbonate supplementation, which can usually be discontinued over time.
儿童生长发育迟缓及/或发育不良常促使进行代谢评估，有时会发现代谢性酸中毒并导致转诊至儿科肾脏病科。肾小管酸中毒（RTA）由于肾脏酸化功能受损导致高氯性代谢性酸中毒，包括短暂性孤立性RTA，这是一种相对常见但描述较少的病症。我们回顾了2023年3月至2024年3月期间转诊至里昂罕见肾脏病中心（MAREGE）的儿科患者，这些患者因孤立性代谢性酸中毒伴线性生长发育迟缓及/或发育不良，排除了全身性、内分泌和胃肠道病因。疑似继发性、遗传性形式或远端RTA的患者被排除。从最初的肾脏病会诊到2025年3月之前的最后一次就诊进行随访分析。数据以中位数[四分位间距]表示，并使用非参数检验进行比较。纳入了35例患者。诊断时，年龄为15.3[13.1 - 25.6]个月，体重和身高标准差（SD）评分分别为 - 1.5[-2.5；-1.0]和 - 1.0[-2.0；0.0]。肾小管评估显示血浆碳酸氢盐水平低（19[18 - 20]mmol/L）、非适应性碳酸氢盐尿（8.0[2.8 - 18.6]mmol/L）以及尿pH升高（7.0[6.4 - 7.4]）。在3.4[1.9 - 4.1]岁时随访2.2[1.4 - 3.
