Grantham J J, Cook L T, Torres V E, Bost J E, Chapman A B, Harris P C, Guay-Woodford L M, Bae K T
Department of Medicine, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA.
Kidney Int. 2008 Jan;73(1):108-16. doi: 10.1038/sj.ki.5002624. Epub 2007 Oct 24.
The Consortium of Radiologic Imaging Studies of Polycystic Kidney Disease (CRISP) recently showed that renal enlargement in autosomal-dominant polycystic kidney disease mimicked exponential growth. We determined the effects of cyst initiation rate, total number, and growth rate on the time-dependent change of total cyst volume (TCV). Mathematical models with equations integrating cyst surface area, volume, and an invariant growth rate constant were used to compute the time-dependent change in volume of solitary and multiple cysts. Multiple expanding cysts increased TCV in an exponential-like pattern even when individual cysts formed at different rates or exhibited different but constant growth rates. TCV depended on the rate of cyst initiation and on the total number of cysts; however, the compounding effect of exponential-like growth was the most powerful determinant of long-term cyst expansion. Extrapolation of TCV data plots for individual subjects back to an age of 18 predicted TCV values within an established range. We conclude that cysts started early in life were the main contributor to eventual TCV while their growth rate primarily determined renal size; although the rate of formation and the ultimate number of cysts also contributed. The good fit between the exponential models and the extrapolated CRISP data indicates that the TCV growth rate is a defining trait for individual patients and may be used as a prognostic marker.
多囊肾病放射影像学研究联盟（CRISP）最近表明，常染色体显性多囊肾病中的肾脏增大呈现出指数增长模式。我们确定了囊肿起始率、总数和生长率对总囊肿体积（TCV）随时间变化的影响。使用整合囊肿表面积、体积和恒定生长速率常数的方程的数学模型来计算单个囊肿和多个囊肿体积随时间的变化。即使单个囊肿以不同速率形成或呈现不同但恒定的生长速率，多个不断增大的囊肿也会以指数样模式增加TCV。TCV取决于囊肿起始率和囊肿总数；然而，指数样生长的复合效应是长期囊肿扩张的最有力决定因素。将个体受试者的TCV数据图外推至18岁时，预测的TCV值在既定范围内。我们得出结论，生命早期开始形成的囊肿是最终TCV的主要贡献者，而它们的生长速率主要决定肾脏大小；尽管囊肿的形成速率和最终数量也有影响。指数模型与外推的CRISP数据之间的良好拟合表明，TCV生长速率是个体患者的一个决定性特征，可作为预后标志物。
