Prospective Cohort External Validation of the UCUC score in patients with Ureteral Calculus

The benefits of avoiding the over-prescription of antibiotics and maintaining stewardship is well known and widely
stressed in the current medical landscape. In an attempt to mitigate over-prescription of antibiotics, the UCUC
calculator was created at our institution in an attempt to assist clinicians in predicting urine culture results in acute
ureteral calculi patients. This was met with intrigue, but was criticized for its confounding variables that could alter
the calculators validity.

Methods or Case Description: This study represents a prospective internal validation evaluating the accuracy of the Ureteral Calculi Urinary Culture (UCUC) calculator that was created at our institution. The study eliminates the previous studies confounding variables and attempts to create an accurate way to predict urine culture results in ureteral calculi patients.

Outcomes: There were 1363 patients analyzed in this prospectively designed study. The calculator was able to accurately predict 57.8% of
positive urine cultures. The sensitivity, specificity, positive predictive values and negative predictive values were
57.6%, 83.3%, 65.5% and 78.1%, respectively.

Conclusion: This represents a prospectively designed validation study that demonstrated no significant difference in diagnostic accuracy when comparing the UCUC score to the presence of urine leukocyte esterase, nitrate or urinary WBC count >20.  External validation of the UCUC score demonstrates that it does not improve upon components of the urinalysis alone.