A Cost–Effectiveness Analysis of Treatment Strategies for Acute Uncomplicated Pyelonephritis in Women

Abstract

At least 250,000 episodes of acute uncomplicated pyelonephritis are treated annually in the emergency department (ED). Trimethoprim-sulfamethoxazole (TMP-SMX) and norfloxacin have both been used as treatments for acute uncomplicated pyelonephritis. To investigate the cost-effectiveness of two outpatient treatment strategies, TMP-SMX and norfloxacin, for acute uncomplicated pyelonephritis in adult women between the ages of 18 and 65 years. Common principles of cost-effectiveness analysis were used for this evaluation. The authors developed a decision tree to estimate the costs and effectiveness of two different treatment strategies: TMP-SMX 160/800 mg twice per day for 10 days and norfloxacin 400 mg twice per day for 10 days. The time frame of the decision tree was 11 days. Outcomes were expressed in U.S. dollars, quality-adjusted life-days (QALDs), and dollars per QALD. Sensitivity analyses were performed on most variables. Norfloxacin is more effective and less costly than the alternative, TMP-SMX. Norfloxacin treatment will save $195.85 per patient, resulting in an aggregate saving of more than $40 million annually. Patients are expected to enjoy a better quality of life with an incremental 0.0601 QALD per patient, if they are treated with norfloxacin. These results are robust across a wide range of probabilities and costs. In this analysis, norfloxacin 400 mg twice a day was a more cost-effective treatment than TMP/SMX 160/800 mg twice a day for women with pyelonephritis.