Paediatric Uncomplicated Cystitis
A 5-year-old girl has two days of dysuria, urinary frequency, and new daytime wetting. She is afebrile at 36.9 °C, alert and tolerating oral fluids, with a soft non-tender abdomen and no costovertebral angle tenderness. She has no vomiting, no previous urinary tract infection, and a normal antenatal renal ultrasound. Urine dipstick shows positive leukocyte esterase and nitrites, and a clean-catch culture is sent. Which treatment is most appropriate?
- A.Oral amoxicillin-clavulanate for five daysCorrect
- B.Oral sodium bicarbonate for symptom relief
- C.Intravenous ciprofloxacin for seven days
- D.Intramuscular ceftriaxone for three days
Explanation
Lower urinary tract infection without fever, vomiting, or systemic toxicity is uncomplicated cystitis, and an oral antibiotic given as an outpatient is the standard of care. A child who is afebrile, well-appearing, and drinking normally has no indication for parenteral therapy, which should be reserved for suspected pyelonephritis, infants under 2 months, sepsis, or inability to tolerate oral intake. Amoxicillin-clavulanate, oral cephalosporins such as cefixime or cephalexin, and trimethoprim-sulfamethoxazole are all acceptable empiric choices, with the final selection adjusted once culture susceptibilities return. A short course of 3 to 5 days is sufficient for cystitis, whereas pyelonephritis requires 7 to 14 days. Escherichia coli causes the large majority of paediatric urinary infections, with Klebsiella and Proteus following, so local resistance patterns should guide the empiric agent. Urinary alkalinisation with sodium bicarbonate may ease dysuria slightly but does not eradicate bacteria and is not a treatment. Fluoroquinolones are avoided in children where alternatives exist because of cartilage and tendon toxicity, and the intravenous route adds no benefit in a well child. Intramuscular ceftriaxone is an option when a child cannot take oral medication or has suspected upper tract disease, but it is unnecessary here. Imaging with renal ultrasound is indicated for recurrent infection, atypical organisms, or febrile infection in young children rather than for a single afebrile episode.
Why each option
- A.
- Correct. An afebrile well child with cystitis needs a short course of an appropriate oral antibiotic as an outpatient.
- B.
- Alkalinising agents may reduce dysuria discomfort but do not eradicate the infecting organism and are not therapy.
- C.
- Fluoroquinolones are avoided in children when alternatives exist, and intravenous therapy is unwarranted in a well, orally tolerant child.
- D.
- Parenteral ceftriaxone is reserved for suspected pyelonephritis, systemic toxicity, or inability to take oral medication.
Reference: Nelson Textbook of Pediatrics, 22nd ed., 2024, Urinary Tract Infections
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