Fever, flank pain, CVA tenderness, dysuria
ABCDE
Fluids, antibiotics within 1 h if septic; relieve obstruction urgently if present.
Order: Urinalysis (WBCs, nitrites) + urine culture
Treat (no imaging needed first): Ceftriaxone IV (or fluoroquinolone — avoid empiric FQ if local resistance >10%); oral cipro/levo if outpatient; duration 5–7 d levofloxacin / 10–14 d others
No improvement → CT (obstruction/stone/abscess)
Order set
- Urinalysis + culture
- FBC, U&E, CRP
- Blood cultures if septic
- Antibiotics
- Imaging if not improving
Criteria
AdmitSepsis, vomiting, obstruction, or pregnancy
ICUSeptic shock, obstructed infected system
VasopressorsSeptic shock
DischargeAfebrile, tolerating oral antibiotics, obstruction excluded/relieved
Clinical detail — differentials, red flags, pitfalls, disposition
Red flags
- Sepsis
- Obstruction
- No improvement at 48–72 h
Differentials
- Lower UTI
- Renal stone
- PID
- Appendicitis
Common mistakes
- Imaging before treating
- Missing obstructed infected system (emergency)
Disposition & follow-up
IV antibiotics; drainage if obstructed; step down to oral.
Discharge package
MedicationsComplete antibiotic course
Follow-upImaging if recurrent/obstruction; urology
Warning symptomsFever, flank pain, vomiting, reduced urine
💊 Treatment detail — doses & preparation
Ceftriaxone3rd-gen cephalosporin
Dose2 g IV OD (meningitis 2 g q12h); gonorrhoea 500 mg–1 g IM once
PreparationIV: 2 g in 50–100 mL NS over 30 min; IM: reconstitute with lidocaine 1%
MonitorBiliary sludging; avoid with calcium-containing IV fluids in same line
Ciprofloxacinfluoroquinolone
Dose500–750 mg PO BD (pyelo step-down, dysentery); 400 mg IV q8–12h
PreparationPO tablets (avoid with Ca²⁺/iron — chelate); IV ready bag
MonitorQT, tendons, dysglycaemia; resistance — culture-guided
Nitrofurantoin (cystitis alt)oral
Dose100 mg MR BD ×5–7 d (lower UTI, eGFR >45)
Preparation50/100 mg capsules with food
MonitorAvoid if pyelonephritis suspected (poor tissue levels)
📖 IDSA / EAU Urinary InfectionReviewed July 2026