Summary

• Most common aetiological organisms are Escherichia coli (80%), Staphylococcus saprophyticus (4%), Klebsiella pneumoniae (4%), and Proteus mirabilis (4%), followed by other bacteria (9%).
• For uncomplicated acute cystitis, first-line treatment is 3 days of trimethoprim/sulfamethoxazole or trimethoprim, or 5 days of nitrofurantoin.
• For complicated cases of cystitis, first line is empirical therapy with a fluoroquinolone antibiotic for 7 to 14 days; treatment should be adjusted based on the results of the urine culture.
• Complicating characteristics include pregnancy; recent instrumentation, including catheterisation or indwelling catheter; male patient; diabetes, immunosuppression; structurally or functionally abnormal urinary bladder; history of recurrent UTIs; history of infection with drug-resistant bacteria; or failed course of treatment for uncomplicated cystitis.