What is the diagnosis for a child with pyelonephritis symptoms, hyperpyrexia, and vomiting, with a history of UTI, treated with antibiotics?

From the Guidelines

This 4-year-old boy with recurrent urinary tract infections (UTIs) should undergo a voiding cystourethrogram (VCUG) to evaluate for vesicoureteral reflux (VUR) after the acute infection resolves, as recommended by the American Academy of Pediatrics guideline for the diagnosis and management of initial UTI in febrile infants and children 2 to 24 months 1.

The child has experienced two documented UTIs - one at 13 months and the current episode with fever, dysuria, vomiting, and positive urine culture for E. coli. Despite normal ultrasound findings both times, the recurrence of febrile UTI strongly suggests the possibility of underlying VUR, which allows backflow of urine from the bladder to the kidneys, increasing infection risk. VCUG is the gold standard for diagnosing VUR and should be performed after the acute infection resolves, typically 2-4 weeks after completing antibiotics.

The procedure involves catheterizing the bladder, filling it with contrast material, and taking images during voiding to detect any reflux. If VUR is identified, management may include continuous antibiotic prophylaxis with trimethoprim-sulfamethoxazole (2-3 mg/kg of trimethoprim once daily) or nitrofurantoin (1-2 mg/kg once daily) until the reflux resolves or surgical correction is performed, as suggested by the guideline 1. The choice of antibiotic should be based on local patterns of susceptibility of coliforms to antimicrobial agents, particularly trimethoprim-sulfamethoxazole and cephalexin, as highlighted in the guideline 1.

Recent studies have shown that short-duration courses of antibiotics (5-7 days) can be effective in treating complicated UTIs, including pyelonephritis, with similar clinical success as long-duration therapy (10-14 days) 1. However, the decision on the duration of antibiotic therapy should be individualized based on the patient's clinical response and the presence of any underlying anatomical abnormalities.

Key points to consider in the management of this patient include:

• The importance of VCUG in diagnosing VUR and guiding management
• The role of continuous antibiotic prophylaxis in preventing recurrent UTIs
• The need for individualized decision-making regarding the duration of antibiotic therapy
• The importance of considering local patterns of susceptibility of coliforms to antimicrobial agents when selecting an antibiotic.

From the Research

Patient Presentation

• The patient is a 4-year-old boy presenting with fever and pain during urination, which began yesterday morning.
• The patient has a history of febrile urinary tract infection at age 13 months, which was treated with antibiotics.
• The patient's current symptoms include suprapubic and right-sided costovertebral angle tenderness, and urinalysis reveals positive nitrites and leukocyte esterase.
• A urine culture shows >100,000 colony-forming units/mL of Escherichia coli.

Diagnosis and Treatment

• The patient was given antibiotics, and his symptoms resolved in 24 hours.
• A repeat renal and bladder ultrasound was normal.
• According to 2, immediate antimicrobial therapy is recommended for acute cystitis, and trimethoprim-sulfamethoxazole, nitrofurantoin, or fosfomycin are appropriate first-line therapies.
• The study 3 compared the effectiveness of amoxicillin/clavulanic acid and trimethoprim in treating urinary tract infections, and found that amoxicillin/clavulanic acid was more effective in non-complicated lower UTIs.
• Another study 4 evaluated the use of amoxicillin-clavulanate for urinary tract infections caused by ceftriaxone non-susceptible Enterobacterales, and found that it may be a useful alternative therapy.

Antibiotic Resistance

• The increasing prevalence of antibacterial resistance among community uropathogens affects the diagnosis and management of urinary tract infections 2.
• A study 5 compared the efficacies and adverse effects of different antibiotics for uncomplicated urinary tract infections, and found that ciprofloxacin and gatifloxacin appeared to be the most effective treatments.
• Guidelines recommend trimethoprim-sulfamethoxazole for empirical treatment of uncomplicated UTI unless resistance in a community exceeds 10% to 20% 6.
• However, surveillance of antimicrobial resistance among uropathogens that cause uncomplicated UTIs is performed rarely, making it challenging to determine the best course of treatment 6.