Significant differences in struvite and cystine stone frequency seen among Chinese nephrolithiasis patients living in North America compared to those living in China.
BACKGROUND
Interracial disparities in nephrolithiasis prevalence have been reported, but the interplay between genetics and the environment for urinary stone disease risk factors is poorly understood. To examine how environment may alter genetic predisposition for stone formation, we established the International Chinese Consortium on Nephrolithiasis (ICCON) as a multi-institutional collaboration to examine patterns of nephrolithiasis presentation between Chinese patients living in different countries.


METHODS
Chinese patients undergoing percutaneous nephrolithotomy (PCNL) at six participating institutions in China and North America over 4 years were reviewed retrospectively. Patient demographics and clinical data were compared between Chinese patients living in China and North America.


RESULTS
A total of 806 patients were included, encompassing 721 Chinese patients living in China and 85 living in North America. Nephrolithiasis patients living in China were more likely to be male (67% vs. 56%, P=0.02), present at a younger age (48.6±15.0 vs. 55.0±13.0 years, P<0.01), and have a lower BMI (24.6±4.0 vs. 25.9±5.7, P=0.04) but were less likely to form struvite stones (5.5% vs. 14.1%, P<0.01). No cystine stone patients were seen in North American Chinese patients, whereas 1.8% of nephrolithiasis patients living in China presented with cystine stones. Similar rates of calcium-based and uric acid calculi as well as urinary pH were seen among both groups.


CONCLUSIONS
Significant differences exist between Chinese nephrolithiasis patients living in China compared to those living in North America, highlighting the importance of environmental factors in addition to genetics in modulating risk for urinary stone disease.
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Thomas
T
Chi
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Manint
M
Usawachintachit
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Pauline
P
Filippou
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
David
D
Bayne
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Weiguo
W
Hu
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Helena
H
Chang
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Lei
L
Xia
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Qi
Q
Chen
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Wei
W
Xue
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Hui
H
He
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Qingzhi
Q
Long
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Olga
O
Arsovska
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Eric
E
Taylor
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Ryan
R
Paterson
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Roger L
RL
Sur
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Ben
B
Chew
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Marshall L
ML
Stoller
1 Department of Urology, University of California, San Francisco, San Francisco, CA 94143, USA ; 2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand ; 3 Beijing Tsinghua Changgung Hospital, Beijing 102218, China ; 4 Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China ; 5 The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China ; 6 University of British Columbia, Vancouver V6T 1Z4, BC, Canada ; 7 Department of Surgery, University of California San Diego, San Diego, CA 92103, USA.
Jianxing
J
Li
Asian Continental Ancestry Group; cystine; kidney calculi; struvite