Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, 4031 Basel, Switzerland.
Department of Clinical Research, University of Basel, 4031 Basel, Switzerland.
J Clin Endocrinol Metab. 2023 Aug 18;108(9):2248-2254. doi: 10.1210/clinem/dgad133.
Differential diagnosis of thiazide-associated hyponatremia (TAH) is challenging. Patients can either have volume depletion or a syndrome of inappropriate antidiuresis (SIAD)-like presentation.
To evaluate the impact of the simplified apparent strong ion difference in serum (aSID; sodium + potassium - chloride) as well as the urine chloride and potassium score (ChU; chloride - potassium in urine) in the differential diagnosis of TAH, in addition to assessment of fractional uric acid excretion (FUA).
Post hoc analysis of prospectively collected data from June 2011 to August 2013 from 98 hospitalized patients with TAH < 125 mmol/L enrolled at University Hospital Basel and University Medical Clinic Aarau, Switzerland. Patients were categorized according to treatment response in volume-depleted TAH requiring volume substitution or SIAD-like TAH requiring fluid restriction. We computed sensitivity analyses with ROC curves for positive predictive value (PPV) and negative predictive value (NPV) of aSID, ChU, and FUA in differential diagnosis of TAH.
An aSID > 42 mmol/L had a PPV of 79.1% in identifying patients with volume-depleted TAH, whereas a value < 39 mmol/L excluded it with a NPV of 76.5%. In patients for whom aSID was inconclusive, a ChU < 15 mmol/L had a PPV of 100% and a NPV of 83.3%, whereas FUA < 12% had a PPV of 85.7% and a NPV of 64.3% in identifying patients with volume-depleted TAH.
In patients with TAH, assessment of aSID, potassium, and chloride in urine can help identifying patients with volume-depleted TAH requiring fluid substitution vs patients with SIAD-like TAH requiring fluid restriction.
噻嗪类药物相关性低钠血症（TAH）的鉴别诊断具有挑战性。患者可能存在血容量不足，也可能存在抗利尿激素不适当分泌综合征（SIAD）样表现。
评估简化的表观强离子差（aSID；钠+钾-氯）以及尿氯和钾评分（ChU；尿中氯-钾）在 TAH 鉴别诊断中的作用，同时评估尿尿酸分数排泄率（FUA）。
这是瑞士巴塞尔大学医院和阿劳大学医学诊所 2011 年 6 月至 2013 年 8 月前瞻性收集 TAH<125mmol/L 的 98 例住院患者数据的事后分析。根据治疗反应将患者分为需要容量替代的血容量不足性 TAH 和需要液体限制的 SIAD 样 TAH。我们计算了 aSID、ChU 和 FUA 对 TAH 鉴别诊断的阳性预测值（PPV）和阴性预测值（NPV）的 ROC 曲线的敏感性分析。
aSID>42mmol/L 时，鉴别血容量不足性 TAH 的 PPV 为 79.1%，<39mmol/L 时 NPV 为 76.5%。对于 aSID 结果不确定的患者，ChU<15mmol/L 时的 PPV 为 100%，NPV 为 83.3%，而 FUA<12%时，鉴别血容量不足性 TAH 的 PPV 为 85.7%，NPV 为 64.3%。
在 TAH 患者中，评估 aSID、尿钾和尿氯有助于确定需要液体替代的血容量不足性 TAH 患者与需要液体限制的 SIAD 样 TAH 患者。
