Single dose treatment failure in women with acute cystitis.

Single dose treatment regimens (SDT) are effective, inexpensive alternatives to longer courses of therapy for adult females with acute cystitis or asymptomatic bacteriuria. A number of SDT regimens consistently cure 85 to 100% of women with acute cystitis and 50 to 80% of women with asymptomatic bacteriuria. However, SDT is inherently less effective than longer regimens because many upper tract infections are not cured. Initial SDT studies suggested that most patients with significant renal invasive disease or underlying urological abnormalities fail therapy. As a result, SDT has been proposed as an efficient strategy to diagnose significant upper tract infections with accompanying pathology that merit additional investigation or treatment. Few studies have refuted or supported this hypothesis. Single-dose treatment studies show an association between the site of infection as determined by the antibody-coated bacteria (ACB) test and treatment outcome. Patients with ACB-negative tests have a cure rate of over 90% in almost all studies in which the organism is susceptible to the agent chosen. Patients with positive ACB tests tend to have treatment failure rates of 30 to 50%. However, imaging studies have not been carried out in parallel with these studies and the validity of using single-dose treatment failure to screen women for significant upper tract pathology has still not been established.