The stone crescent of Anatolia.

Objectives: To assess the largest stone composition data available and to present the variations in the stone composition according to gender and different climatic environments in Turkey.

Methodology: Data for a total of 24 768 urinary stone patients from the Turkish Mineral Research and Exploration Institute were evaluated. X-ray diffraction crystallography was used for analysis and the Köppen-Trewartha classification was used to assess the climatic features of the cities. After the assessment, the cities were divided into two groups-those with a continental climate (Dc) were defined as inland areas and the others (Non-Dc) were defined as coastal areas.

Results: The male-to-female ratio was 2.2:1. Amongst the patients, 53.7% had pure stones, while 46.3% had mixed-type stones. The most common type of stone was calcium oxalate in both pure and mixed stone groups. Given the climate patterns, the stone ratio between regions with a Dc climate and a Non-Dc climate was approximately 2:3. Cystine and uric acid stones were observed more frequently in inland regions, while calcium oxalate, whewellite, and struvite stones were observed more frequently in coastal areas (P = .005, P < .001, P < .001, P = .002, P = .002, respectively). Calcium oxalate stones were found at a higher rate in men, while cysteine, struvite, and calcium phosphate stones were more common in women (P < .001, P = .003, P < .001, P < .001, respectively).

Conclusion: This study provides the most comprehensive data on the stone disease in Turkey. Considering the distribution of stone disease in Turkey, the frequency of analysed stones had parallels with the temperature averages and climate features, presenting crescent-like distribution.