Changes in stone composition over two decades: evaluation of over 10,000 stone analyses

Area of Science:

• Nephrology
• Urology
• Epidemiology

Background:

• Kidney and ureteral stone disease epidemiology is dynamic.
• Understanding temporal trends in stone composition is crucial for public health and clinical management.
• Previous studies have indicated shifts in stone types, but long-term gender-specific analyses are less common.

Purpose of the Study:

• To investigate changes in renal and ureteral stone composition between 1990 and 2010.
• To identify gender-specific trends in stone types over a 20-year period.

Main Methods:

• Retrospective review of renal and ureteral stones submitted to a single laboratory in Massachusetts.
• Analysis of stone composition using infrared spectroscopy and/or polarizing microscopy.
• Evaluation of 11,099 stones from 1990 and 2010, comparing demographic and compositional data.

Main Results:

• The proportion of stones from females increased significantly from 1990 to 2010.
• In women, uric acid stones increased, while struvite stones decreased; apatite content in calcium stones decreased.
• In men, cystine and struvite stones significantly increased; apatite content in calcium stones increased, with no change in uric acid stones.

Conclusions:

• Stone disease epidemiology shows significant gender-specific evolution.
• Observed changes may be linked to population shifts like obesity, but other etiological factors require further investigation.
• These findings highlight the need for gender-tailored approaches in stone prevention and treatment strategies.