St-Louis Hospital, Necker Hospital, Assistance Publique Hôpitaux de Paris, and Paris V and Paris VII University, Paris Cedex, France.
J Urol. 2010 Apr;183(4):1412-6. doi: 10.1016/j.juro.2009.12.016. Epub 2010 Feb 20.
We examined whether stone composition in pregnant women reflects peculiar pathophysiological conditions.
We analyzed in detail the composition of stones from 244 pregnant women 17 to 44 years old and from 5,712 nonpregnant women in the same age range, as recorded between January 1991 and December 2007. Clinical features were also recorded. All stones were analyzed by morphological examination coupled with infrared spectroscopy. The 2 patient groups were compared by clinical and biochemical characteristics.
Stone episodes in pregnant women manifested mainly in trimesters 2 and 3 (39% and 46%, respectively). Spontaneous passage was noted in 81% of pregnant vs 47% of nonpregnant women (p <0.0001). Calcium phosphate, mainly in the form of carbapatite, was the main stone component in 65.6% of pregnant vs 31.4% of nonpregnant women (p <0.0001). Octacalcium phosphate pentahydrate, a transition phase in calcium phosphate stone formation, was found in a 5-fold higher proportion in carbapatite stones in pregnant than in nonpregnant women, a finding also suggesting recent stone formation during pregnancy.
The composition of stones manifesting during pregnancy clearly differs from that of stones formed in nonpregnant women of childbearing age, suggesting a different pathophysiology specific to the pregnant state. In view of the pH dependency of calcium phosphate stones factors that increase the physiological elevation in maternal urinary calcium excretion and pH are likely to have a role in the preferential formation of calcium phosphate stones during pregnancy.
我们研究了孕妇结石的成分是否反映了特殊的病理生理状况。
我们详细分析了 1991 年 1 月至 2007 年 12 月期间记录的 244 名 17 至 44 岁的孕妇和 5712 名年龄相同的非孕妇的结石成分。还记录了临床特征。所有结石均通过形态学检查结合红外光谱分析进行分析。通过临床和生化特征比较两组患者。
孕妇结石发作主要发生在妊娠中期 2 期和 3 期（分别为 39%和 46%）。81%的孕妇结石可自行排出，而非孕妇仅为 47%（p<0.0001）。磷酸钙主要以碳磷灰石的形式存在，孕妇中占 65.6%，而非孕妇中占 31.4%（p<0.0001）。八水磷酸氢钙五水合物是磷酸钙结石形成的过渡相，在孕妇的碳磷灰石结石中发现比例高出 5 倍，这一发现也表明在妊娠期间存在近期结石形成。
妊娠期间出现的结石成分明显不同于生育年龄的非孕妇形成的结石，表明妊娠状态下存在特定的病理生理学差异。鉴于磷酸钙结石对 pH 的依赖性，增加母体尿钙排泄和 pH 的生理性升高的因素可能在妊娠期间优先形成磷酸钙结石中起作用。
