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Changing incidence of factitious renal stone disease .

PURPOSE
We sought to describe patterns of factitious urinary stone submission over time by investigating a contemporary stone analysis database and comparing two distinct time points.


MATERIALS AND METHODS
We retrospectively reviewed a single stone analysis lab database at two time points, 1990 and 2010, and compared total incidence of factitious stone submission, as well as gender patterns and type of factitious stone submitted.


RESULTS
A total of 27,014 stones were analyzed, 16,216 (60%) from 1990 and 10,798 (40%) from 2010 with a decrease in total incidence from 2.6% (428/16,216) in 1990 to 1.2% (131/10,798) in 2010 (p < 0.001). In 1990, women were significantly more likely to submit a factitious stone (RR 1.5, 95% CI 1.4 - 1.7, p < 0.001), while in 2010 there was no gender difference (RR 0.9, 95% CI 0.8 - 1.03, p < 0.05). Plant material and geologic material represented the most common factitious stone types respectively, in both 1990 and 2010.


CONCLUSION
In the largest contemporary review of spurious urinary stones, we find a decreased incidence and increased gender equivalence of factitious urinary stones in 2010 compared to 1990. .