Department of Nephrology, Erasmus MC, Rotterdam, The Netherlands.
Malar J. 2012 Jan 26;11:26. doi: 10.1186/1475-2875-11-26.
In the pathophysiology of hyponatraemia in malaria, the relative contribution of appropriate and inappropriate arginine vasopressin (AVP) release is unknown; the trigger for inappropriate AVP release is also unknown.
Serum copeptin, a stable and sensitive marker for AVP release, was analysed in a large cohort of patients with imported malaria (204 patients) and in a small prospective substudy (23 patients) in which urine sodium and osmolality were also available. Hyponatraemia was classified as mild (serum sodium 131-134 mmol/l) and moderate-to-severe (< 131 mmol/l).
Serum copeptin on admission was higher in patients with moderate-to-severe hyponatraemia (median 18.5 pmol/L) compared with normonatraemic patients (12.7 pmol/L, p < 0.05). Despite prompt fluid resuscitation, the time to normalization of serum sodium was longer in patients with moderate-to-severe hyponatraemia (median 2.9 days) than in patients with mild hyponatraemia (median 1.7 days, p < 0.001). A poor correlation was found between serum sodium and copeptin levels on admission (rs = -0.17, p = 0.017). Stronger correlations were identified between serum C-reactive protein and copeptin (rs = -0.36, p < 0.0001) and between serum C-reactive protein and sodium (rs = 0.33, p < 0.0001). Data from the sub-study suggested inappropriate AVP release in seven of 13 hyponatraemic malaria patients; these patients had significantly higher body temperatures on admission.
In hyponatraemic patients with imported malaria, AVP release was uniformly increased and was either appropriate or inappropriate. Although the exact trigger for inappropriate AVP release remains unknown, the higher body temperatures, correlations with C-reactive protein and long normalization times of serum sodium, suggest an important role of the host inflammatory response to the invading malaria parasite.
在疟疾低钠血症的病理生理学中，适当和不适当的精氨酸血管加压素（AVP）释放的相对贡献尚不清楚；不适当 AVP 释放的触发因素也尚不清楚。
分析了大量输入性疟疾患者（204 例患者）和一个小的前瞻性亚研究（23 例患者）中的血清 copeptin，该亚研究中也可获得尿钠和尿渗透压数据。低钠血症分为轻度（血清钠 131-134mmol/L）和中重度（<131mmol/L）。
与正常血钠患者（12.7pmol/L，p<0.05）相比，中重度低钠血症患者入院时的血清 copeptin 更高（中位数 18.5pmol/L）。尽管迅速进行液体复苏，但中重度低钠血症患者血清钠正常化的时间较长（中位数 2.9 天），而轻度低钠血症患者的时间较短（中位数 1.7 天，p<0.001）。入院时血清钠与 copeptin 水平之间相关性较差（rs=-0.17，p=0.017）。血清 C 反应蛋白与 copeptin 之间（rs=-0.36，p<0.0001）和血清 C 反应蛋白与钠之间（rs=0.33，p<0.0001）存在更强的相关性。亚研究中的数据表明，13 例低钠血症疟疾患者中有 7 例存在不适当的 AVP 释放；这些患者入院时的体温明显更高。
在输入性疟疾低钠血症患者中，AVP 释放普遍增加，既可以是适当的，也可以是不适当的。尽管不适当 AVP 释放的确切触发因素尚不清楚，但较高的体温、与 C 反应蛋白的相关性以及血清钠正常化时间较长，提示宿主对入侵疟原虫的炎症反应起着重要作用。
