What criterion is used for continuous antibiotic prophylaxis in recurrent UTIs?

Continuous antibiotic prophylaxis for recurrent urinary tract infections (UTIs) is often considered based on the frequency of infections. Specifically, a common criterion is the number of UTIs that occur within a specified timeframe, such as having three or more UTIs in a year. This frequency indicates a pattern that may require intervention to prevent further infections and improve the patient's quality of life.

In practice, using the frequency of UTIs as a criterion helps healthcare providers identify patients who may benefit from prophylactic antibiotics to reduce the risk of recurrent infections. It allows for a targeted approach, as not all individuals who have occasional UTIs will need such preventive measures.

In contrast, factors like age, the presence of urinary obstruction, or the observation of renal stones may be important in evaluating a patient's overall risk or guiding further investigation and management, but they do not directly determine the need for continuous prophylactic antibiotics as clearly as the frequency of UTIs does. Therefore, the focus on the number of occurrences provides a direct rationale for initiating prophylaxis in affected individuals.