Pediatric Urinary Tract Infections

Joshua A. Hodge, Maj, USAF, MC

Staff Family Physician

Andrews AFB, MD

Overview

• Background• Diagnosis• Treatment• Follow up• Prevention• Imaging• Vesiculoureteral reflux (VUR)• Summary

Background

• Most common serious bacterial infection in young children – 5% of febrile infants

• Prevalence – By age 7: 8% girls, 2% boys– Highest rate in first year of life– Higher in Caucasians– Higher in uncircumcised boys

• Most common organism: E. coli- 80%

Background

• Symptoms systemic in early childhood– Fever*– Irritability– Lethargy– Anorexia– Emesis

• Potential sequelae– Renal scarring– Chronic renal failure– HTN

Background

• Anatomic risk factors– Vesiculoureteral reflux (VUR)

• More common in girls

– Obstruction– Posterior urethral valves

• Boys

– Voiding dysfunction– Bladder diverticulum

Background

• Associated risk factors– Constipation– Encoporesis– Bladder instability– Infrequent voiding

• Unsubstantiated risks – Bathing– Back-to-front wiping

Diagnosis

• Single organism identified on culture– Suprapubic aspirate > 1,000 cfu/mL– Catheter specimen > 10,000 cfu/mL– Clean catch specimen > 100,000 cfu/mL– Urine bags not recommended

Diagnosis

• Urinalysis– Not helpful if clinical suspicion high

• i.e. older children with classic symptoms

– Useful if low likelihood of UTI • Non-dilute urine (sg > 1.005)• Neg nitrate and leuk esterase• Negative predictive value > 95%

• Blood cultures not useful

Treatment

• Initiate immediately after culture drawn– Reduces severity of renal scarring

• Oral route preferred

• 7-14 day course is standard– 2-4 days appears to be as effective

• Not yet recommended

Treatment

Antibiotic Daily DosageAmoxicillin* 20-40mg/kg in 3 doses

Cefixime (Suprax) 8mg/kg in 2 doses

Cefpodoxime (Vantin) 10mg/kg in 2 doses

Cefprozil (Cefzil) 30mg/kg in 2 doses

Cephalexin (Keflex) 50-100mg/kg in 4 doses

Loracarbef (Lorabid) 15-30mg/kg in 2 doses

Sulfisoxazole (Gantrisin) 120-150mg/kg in 4 doses

Trimethoprim/

Sulfamethoxazole (Bactrim)

6-12mg/kg & 30-60mg/kg

In 2 doses

Follow Up

• AAP Recommendation: 48 hours – If not improving repeat culture &

immediate renal ultrasound

– No evidence to support repeat culture/test of cure

Committee on Quality Improvement, Subcommittee on Urinary Tract Infection. Practice parameter: the diagnosis, treatment, and evaluation of the initial urinary tract infection in febrile infants and young children. Pediatrics 1999;103:843-52.

Prevention

• Rates of recurrence– 12% of children < 5 years old

– 18% of infants < 6 months

• Prophylactic antibiotics– Recommended by AAP while waiting for

imaging

– Efficacy questioned

Prevention

Antibiotic Daily Dosage

Methenamine mandelate (Mandelamine)

75mg/kg in 2 doses

Nalidixic acid (NegGram) 30mg/kg in 2 doses

Nitrofurantoin (Macrobid) 1-2mg/kg once per day

Sulfisoxazole (Gantrisin) 10-20mg/kg in 2 doses

Trimethoprim/

sulfamethoxazole (Bactrim)

2mg/kg & 10mg/kg nightly or 5mg/kg & 25mg/kg 2x/week

Prevention

• Circumcision– Lowers UTI rate in boys

• NNT = 111 to prevent one UTI– Surgical complication rate = 1%– Benefit does not outweigh risk and not

recommended

Imaging

• Who to image?– AAP

• All children 2 months to 2 years of age with first UTI

• Renal ultrasound• Cystogram

–Voiding cystourethrogram (VCUG)–Radionuclide cystogram (RNC)

Imaging

• Who to image?

– Cincinnati Children’s Hospital• All boys• Girls < 36 months• Girls 3-7 with fever > 38.5º C (101.3º F)• Same modalities recommended as AAP

Evidence based clinical practice guideline for medical management of first time acute urinary tract infection in children 12 years of age or less. Cincinnati, Ohio: Cincinnati Children’s Hospital Medical Center, 2005.

Imaging

• Renal ultrasound– GU tract anatomy– Evaluate renal scarring

• DMSA (renal cortical scan)– Differentiates pyelonephritis from cystitis– Assesses renal scarring

Imaging

• Cystogram- identify and grade vesicoureteral reflux (VUR)– Voiding cystourethrogram (VCUG)

• OK for girls and boys• Demonstrates GU anatomy plus VUR

– Radionuclide cystogram (RNC) • Low amount of radiation• Girls only

–Little anatomic detail

Vesicoureteral Reflux (VUR)

• Concern for pyelonephritis & renal scarring

• Prevalence in females < 18 yo– Grade I- 7%– Grade II- 22%– Grade III- 6%– Grade IV- 1%– Grade V- <1%

Vesicoureteral Reflux

• Standard treatment options– Antibiotics

• Studies of prophylactic antibiotics have not included children with VUR

– Surgery– Antibiotics + surgery

Vesicoureteral Reflux

• Unclear if clinical benefits to treating VUR– Only severe VUR (Grades IV & V) associated

with recurrent UTI and pyelonephritis • < 2% of all cases of VUR• No causal relationship with scarring

– Risk of UTI = between surgical & medical groups– Abx + surgery reduced # of UTIs and pyelo but

no renal damage noted in either group at 5 years

Wheeler DM, et al. Interventions for primary VUR. Cochrane Database Syst Rev. 2004(3):CD001532

Summary

• Urine culture necessary for diagnosis• Short courses of antibiotics may be as

effective as longer courses• Prophylactic antibiotics are an option but

may not provide much clinical benefit• Routine imaging does not appear to affect

outcomes• Diagnosing VUR does not appear to affect

outcomes

References• Alper BS, Curry SH. Urinary tract infection in children. Am Fam

Physician 2005;72:2483-8.• Committee on Quality Improvement, Subcommittee on Urinary Tract

Infection. Practice parameter: the diagnosis, treatment, and evaluation of the initial urinary tract infection in febrile infants and young children. Pediatrics 1999;103:843-52.

• Currie ML, et al. Follow-up urine cultures and fever in children with urinary tract infection. Arch Pediatr Adolesc Med 2003;157:1237-40.

• Evidence based clinical practice guideline for medical management of first time acute urinary tract infection in children 12 years of age or less. Cincinnati, Ohio: Cincinnati Children’s Hospital Medical Center, 2005.

• Michael M, et al. Short versus standard duration oral antibiotic therapy for acute urinary tract infection in children. Cochrane Database Syst Rev 2004;(4):CD003966

References• Roberts KB. The AAP practice parameter on urinary tract infections

in febrile infants and young children. Am Fam Physician 2000;62:1815-22.

• Le Saux N, Pham B, Mohoer D. Evaluating the benefits of antimicrobial prophylaxis to prevent urinary tract infections in children: a systematic review. CMAJ 2000; 163:523-9.

• Michael M, et al. Short compared with standard duration of antibiotics treatment for urinary tract infection: a systematic review of randomised controlled trials. Arch Dis Child 2002;87:118-23.

• Singh-Grewal D, Macdessi J, Craig J. Circumcision for the prevention of urinary tract infection in boys: a systematic review of randomized trials and observational studies. Arch Dis Child 2005;90:853-58.

• Williams GJ, Lee A, Craig JC. Long-term antibiotics for preventing recurrent urinary tract infection in children. Cochrane Database Syst Rev 2004;(4):CD001534.

• Wheeler DM, et al. Interventions for primary vesicoureteric reflux. Cochrane Database Syst Rev 2004;(3):CD001532.