Background

Tubular dysfunction can cause electrolyte disturbances with potentially serious consequences. We studied the epidemiology and outcomes of electrolyte disturbances and tubular dysfunction among critically ill children and evaluated their relationships with acute kidney injury (AKI).

Methods

We conducted a prospective cohort study recruiting children aged 1 month to ≤ 18 years old admitted to the pediatric intensive care unit (PICU) from 6/2020 to 6/2021. The serum levels of sodium, potassium, calcium, phosphate, and magnesium were reviewed and simultaneous urinary investigations for tubular function were performed among children with electrolyte disturbances.

Results

Altogether there were 253 episodes of admission. The median (interquartile) age was 4.9 (1.3–11.0) years and 58.1% were male. The median number of electrolyte disorders was 3 (2–4) types. Hypophosphatemia (74.2%), hypocalcemia (70.3%) and hypermagnesemia (52.9%) were the three commonest types of disturbances. Urinary electrolyte wasting was commonly observed among children with hypomagnesemia (70.6%), hypophosphatemia (67.4%) and hypokalemia (28.6%). Tubular dysfunction was detected in 82.6% of patients and urinary β2-microglobulin level significantly correlated with the severity of tubular dysfunction (p < 0.001). The development of tubular dysfunction was independent of AKI status. Tubular dysfunction was associated with mortality (p < 0.001) and was an independent predictor of PICU length of stay (LOS) (p < 0.001). The incorporation of the tubular dysfunction severity into the AKI staging system improved the prediction of PICU LOS.

Conclusions

Tubular dysfunction was associated with both morbidity and mortality in critically ill children and its assessment may help to capture a more comprehensive picture of acute kidney insult.

Graphical abstract

中文翻译：

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儿童肾小管功能障碍的影响及其与急性肾损伤的关系

背景

肾小管功能障碍可导致电解质紊乱，并可能造成严重后果。我们研究了危重儿童电解质紊乱和肾小管功能障碍的流行病学和结果，并评估了它们与急性肾损伤（AKI）的关系。

方法

我们进行了一项前瞻性队列研究，招募了2020年6月至2021年6月入住儿科重症监护病房（PICU）的1个月至≤18岁的儿童。对电解质紊乱儿童的钠、钾、钙、磷酸盐和镁的血清水平进行了检查，并同时进行了肾小管功能的尿液检查。

结果

总共有253集入场。中位年龄（四分位数）为 4.9（1.3-11.0）岁，其中 58.1% 为男性。电解质紊乱的中位数为 3 (2-4) 种类型。低磷血症（74.2%）、低钙血症（70.3%）和高镁血症（52.9%）是三种最常见的紊乱类型。尿电解质浪费常见于低镁血症（70.6%）、低磷血症（67.4%）和低钾血症（28.6%）的儿童。82.6% 的患者检测到肾小管功能障碍，尿 β2 微球蛋白水平与肾小管功能障碍的严重程度显着相关 (p < 0.001)。肾小管功能障碍的发生与 AKI 状态无关。肾小管功能障碍与死亡率相关 (p < 0.001)，并且是 PICU 住院时间 (LOS) 的独立预测因素 (p < 0.001)。将肾小管功能障碍严重程度纳入 AKI 分期系统改善了 PICU LOS 的预测。

结论

肾小管功能障碍与危重儿童的发病率和死亡率相关，其评估可能有助于更全面地了解急性肾损伤。

图形概要