Randomized clinical trial in which women aged 18 or older and with symptoms of uncomplicated lower urinary tract infection and a positive urine dipstick analysis will be randomized to one of the following four groups: 2-day 3 g fosfomycin o.d., 3-day pivmecillinam 400 mg. t.i.d, 5-day nitrofurantoin 100 mg t.i.d. or a single dose of 3 g of fosfomycin. Sample: 1,000 patients. Two co-primary endpoints are considered: clinical effectiveness at day 7 and bacteriological eradication at day 14. Follow-up visits are scheduled at days 7 (phone call), 14 and 28 for assessing evolution. Urine samples will be collected in the three on-site visits and urine cultures performed.

Uncomplicated lower urinary tract infections (LUTI) represent a common problem in primary care. Resistance of uropathogens to common antibiotics has significantly increased in the last years. Current local guidelines recommend the use of a single 3 g dose of fosfomycin for these infections, but most general practitioners prefer short-course therapies to single-dose therapy. No study has compared head-to-head short course antimicrobial agents for uncomplicated LUTIs. Therefore, the aim of this randomized clinical trial is to compare three different short-course antibiotic therapies with single-dose fosfomycin for uncomplicated LUTIs in adult women. This will be a pragmatic, multicenter, parallel group, open randomized trial. Women aged 18 or older and with symptoms of uncomplicated LUTI and a positive urine dipstick analysis will be randomized to one of the following four groups: 2-day 3 g fosfomycin o.d., 3-day pivmecillinam 400 mg. t.i.d, 5-day nitrofurantoin 100 mg t.i.d. or a single dose of 3 g of fosfomycin. Sample: 1,000 patients. Two co-primary endpoints are considered: clinical effectiveness, defined as resolution of symptoms, answered by the patients at day 7, and bacteriological eradication (proportion of patients bacteriologically cured) at day 14. Patients will be given a symptom diary for seven days. Follow-up visits are scheduled at days 7 (phone call), 14 and 28 for assessing evolution. Urine samples will be collected in the three on-site visits and urine cultures performed. If positive, antibiograms for the 3 antibiotics studied will be performed.

Inclusion Criteria:

Women of 18 years of age or older, with clinical features of uncomplicated community-acquired lower urinary tract infection including:

• At least one of four key symptoms of lower urinary tract infection: dysuria, urgency including nycturia, frequency, and suprapubic tenderness that could be attributed to an uncomplicated lower urinary tract infection, and no alternative explanation (i.e. symptoms suggestive of sexually-transmitted infection or vulvovaginitis), and
• A urine dipstick analysis positive for either nitrites or leukocyte esterase.

Exclusion Criteria:

• Male sex
• High suspicion of pyelonephritis (i.e. fever ≥ 37.5°C or flank pain/tenderness)
• Any condition that may lead or predispose to complicated urinary infection (i.e. indwelling urinary catheter, pregnancy, immunosuppressive therapy, abnormal urinary tracts, recurrent urinary tract infection, severe neurological disease affecting the bladder)
• Pregnancy or planned pregnancy
• Symptoms consistent with urinary tract infection in the preceding 4 weeks
• Patients taking long-term antibiotic prophylaxis
• Ongoing antibiotic therapy or use of any systemic antibiotic in the previous 7 days
• Symptoms correlating with differential diagnosis (i.e. vaginal discharge or pain)
• Hypersensitivity or allergy to β lactams, nitrofurantoin and/or fosfomycin
• Moderate to severe chronic renal insufficiency
• Pre-existing polyneuropathy
• History of lung or liver reaction or peripheral neuropathy after previous use of nitrofurantoin
• Glucose-6-phosphate dehydrogenase deficiency
• Porphyria or systemic primary carnitine deficiency or of the type organic aciduria (i.e. methylmalonic aciduria and propionicacidaemia)
• Esophageal stricture
• Current intake of allopurinol or probenecid or valproate
• Currently part of another randomized clinical trial
• Previous enrolment in the proposed study
• Patients living in long-term institutions; and/or
• Difficulty in conducting scheduled follow-up visits

On request

On request after publication.

Principal investigator's email (carles.llor@gmail.com)