Oral Antibiotics Alone in Children Aged 4 Weeks to 2 Months With a Urinary Tract Infection

Who May Qualify: 1. Clinical suspicion of urinary tract infection irrespective of the presence of fever. 2. Clinically stable (i.e., not respiratory or circulatory affected, septic, or meningeal). 3. 4 weeks to 2 months of age (corrected age, if premature). All children who do not receive any empirical antibiotic therapy but have a positive urine culture can be included if the clinical suspicion of urinary tract infection persists. A positive urine culture is defined as: - Suprapubic bladder aspiration: any growth of bacteria. - Sterile intermittent catheterization: monoculture with ≥10\^3 colony forming units per milliliter (cfu/ml). - Midstream urine x 2: monoculture with the same bacteria in both tests with ≥10\^4 cfu/ml. - Midstream urine x 2: monoculture with the same bacteria in both tests with ≥10\^5 cfu/ml in one test and 10\^3 cfu/ml in another test. Who Should NOT Join This Trial: 1. Non-Danish civil registration number. 2. High-risk medical history. 1. Previous urinary tract infection. 2. Prophylactic antibiotic treatment. 3. Known urogenital abnormality (i.e., hydronephrosis (pyelectasis ≥10 mm or/and caliectasis ≥5 mm); hydroureter; vesicoureteral reflux; multicystic dysplasia; renal dysplasia; renal hypoplasia; renal agenesis; duplex kidney; ectopic placed kidneys; polycystic kidney disease; neurogenic bladder dysfunction; and hypospadias). 4. Previous hospitalization needing antibiotic therapy. 3. Markedly elevated c-reactive protein indicating bacteremia. 4. Elevated creatinine. 5. Oral therapy is not possible (e.g., frequent vomiting or excessive regurgitation). Always talk to your doctor about whether this trial is right for you.