However, the risk of UTI as an occult source of infection remains substantial in fully immunized children, depending upon age, gender, and circumcision status [45]. This risk guides recommendations for evaluation and treatment in these patients [70].

●For children with FWS who are completely immunized, we suggest that girls less than 24 months of age, uncircumcised boys less than 12 months, and circumcised boys <6 months receive a urinalysis and urine culture. Urine for culture should be collected by catheterization or, in exceptional cases (eg, tight phimosis or severe labial adhesions), suprapubic aspiration. Bag specimens should not be sent for culture because they are frequently contaminated. (See "Urine collection techniques in infants and children with suspected urinary tract infection" and 'Urinary tract infection' above.)

●For girls >24 months of age, uncircumcised boys >12 months of age and circumcised boys >6 months of age, all of whom have been completely immunized, we do not suggest routine laboratory evaluation or presumptive treatment with antibiotics. However, urinalysis and urine culture should be obtained in those with signs or symptoms of UTI, which must be specifically sought (eg, dysuria, frequency, abdominal pain, back pain, new onset incontinence). In addition, children with a prior history of UTI, urogenital anomalies, or prolonged fever (>48 hours) warrant urinalysis and urine culture. (See 'Urinary tract infection' above.)

Some experts suggest that a high fever without a source (>39°C [102.2°F]) is sufficient justification for urine culture on the first visit in uncircumcised boys 24 months of age or younger (algorithm 1). (See "Urinary tract infections in infants and children older than one month: Clinical features and diagnosis", section on 'Decision to obtain'.)

●Children with FWS who are completely immunized against Hib and pneumococcus, with either PCV7 or PCV13, meet criteria for urine testing, and have an abnormal urinalysis should be treated for UTI. Appropriate follow-up should be arranged. ]

Upper urinary tract infections (ie, acute pyelonephritis) may lead to renal scarring, hypertension, and end-stage renal dysfunction.

Urinary tract infections (UTI) are a common and important clinical problem in childhood.

Empiric Antibiotic Therapy —

To prevent renal damage. A delay in the treatment of febrile UTIs is associated with increased risk for renal scarring.





Choice of agent — A Gram-stained smear of the urine, if readily available, can help guide decisions regarding empiric therapy. The ultimate choice of antimicrobial therapy is based upon the susceptibilities of the organism isolated.


Agent Rationale
Third-generation cephalosporins (eg, cefpodoximecefiximecefdinirceftibutencefotaximeceftriaxone) and aminoglycosides (eg, gentamicinamikacin) are appropriate first-line agents for empiric treatment of UTI in children. They cover Escherichia coli the most common bacterial cause of UTI; it accounts for approximately 80 percent of UTI in children [13,14].


However, these drugs are not effective in treating Enterococcus and should not be used as monotherapy for patients in whom enterococcal UTI is suspected (eg, those with a urinary catheter in place, instrumentation of the urinary tract, or an anatomical abnormality). In such patients, amoxicillin or ampicillin should be added. Hydration status and renal function should be assessed in patients who are treated with aminoglycosides.



Oral therapy — Most children older than two months of age who are not vomiting can be treated with orally administered antimicrobials [3,27]. Close contact with the family should be maintained for the first two to three days of therapy; the seriousness of the infection and the need for completion of the entire course of therapy should be stressed.

We suggest a cephalosporin as the first-line oral agent in the treatment of UTI in children without genitourinary abnormalities [4,5,28,29]. In a randomized, controlled trial of 306 children 1 to 24 months of age with a febrile UTI,

oral therapy with cefixime for 14 days was as effective as intravenous (IV) therapy with cefotaxime for three days followed by oral therapy with cefixime [4].

The rates of symptom resolution (mean time to defervescence approximately 24 hours), sterilization of the urine (100 percent), reinfection (4.6 and 7.2 percent), and renal scarring at six months (9.8 and 7.2 percent) did not differ between groups.

A similar trial in children 6 months to 16 years, albeit limited by imbalances in comparability of treatment groups at baseline and high drop-out rates, found once-daily therapy with ceftibuten to be comparable to initial therapy with ceftriaxone followed by ceftibuten [28]. Oral amoxicillin-clavulanate (50 mg/kg per day in three divided doses) also was shown to be as effective as parenteral therapy followed by oral therapy in a multicenter, randomized trial [30]. However, amoxicillin-clavulanate is associated with increasing rates of resistance. In a child with a penicillin and cephalosporin allergy, treatment with TMP-SMX, or ciprofloxacin (if the local resistance rates to TMP-SMX are known to be high) and close follow-up of the antimicrobial sensitivity results is a reasonable strategy.

Cefiximecefdinir, and ceftibuten are dosed as follows:

Cefixime (16 mg/kg by mouth on the first day, followed by 8 mg/kg once daily to complete therapy) (see 'Duration of therapy' below)

Cefdinir (14 mg/kg by mouth once daily)

Ceftibuten (9 mg/kg by mouth once daily)

Other cephalosporins that may be used for oral therapy include cefpodoxime (10 mg/kg divided in two doses) or cephalexin (50 to 100 mg/kg per day in three divided doses) [3,31]. However, no large trials have specifically examined the efficacy of these agents for pediatric UTI.

Amoxicillin and ampicillin are not routinely recommended for empiric therapy because of the high rate of resistance of E. coli. Similarly, amoxicillin-clavulanate, first-generation cephalosporins (eg, cephalexin), and TMP-SMX should be used with caution, especially when pyelonephritis is suspected, because of the increasing rates of resistance to these drugs in some communities [13,15-20,22,32-34]. The rate of E. coli producing extended spectrum beta-lactamases appears to be increasing [35].

Fluoroquinolones (eg, ciprofloxacin) are effective for E. coli, and resistance in children is rare. However, widespread use of fluoroquinolones is leading to increased resistance among other bacteria [36-38], and ciprofloxacin should not be routinely used as a first-line agent [39]. The American Academy of Pediatrics (AAP) Committee on Infectious Diseases recommends that the use of ciprofloxacin for UTI in children be limited to UTI caused by Pseudomonas aeruginosa or other multidrug-resistant, gram-negative bacteria [40]. (See "Fluoroquinolones".)

Oral agents that are excreted in the urine but do not achieve therapeutic serum concentrations (eg, nalidixic acid, nitrofurantoin) should not be used to treat UTI in febrile infants and young children in whom renal involvement is likely because parenchymal and serum concentrations may be insufficient to treat pyelonephritis or urosepsis [3].

Parenteral therapy

Inpatient parenteral therapy — In-hospital parenteral therapy generally is indicated for children with [3,6-8]:

●Age <2 months (data regarding outpatient therapy for infants <2 months of age are lacking)

●Clinical urosepsis (eg, toxic appearance, hypotension, poor capillary refill)

●Immune compromise

●Vomiting or inability to tolerate oral medication

●Lack of adequate outpatient follow-up (eg, no telephone, live far from hospital, etc)

●Failure to respond to outpatient therapy (see 'Response to therapy' below)

Cephalosporins (eg, cefotaximeceftriaxonecefepime) and aminoglycosides (eg, gentamicin) are appropriate first-line parenteral agents for empiric treatment of UTI in children. Definitive therapy is based upon the results of urine culture and sensitivities.

Acceptable inpatient treatment regimens include the combination of ampicillin and gentamicin; gentamicin alone; or a third- or fourth-generation cephalosporin [9,41,42]. Ampicillin should be included if enterococcal UTI is suspected. (See 'Recent antibiotic exposure' below.)

The doses are as follows [3,43]:

Ampicillin (100 mg/kg/day IV divided in four doses)

Gentamicin (7.5 mg/kg/day IV divided in three doses)

Cefotaxime (150 mg/kg per day IV divided in three or four doses)

Ceftriaxone (50 to 75 mg/kg per day IV)

Cefepime (100 mg/kg per day divided in two doses for children weighing ≤40 kg, maximum daily dose 1 g; 500 mg twice per day for children weighing >40 kg)

Parenteral antibiotics should be continued until the patient is clinically improved (eg, afebrile) and able to tolerate oral liquids and medications [3]. (See 'Duration of therapy' below.)

Outpatient parenteral therapy — Once-daily parenteral administration of gentamicin or ceftriaxone in a day treatment center may avoid the need for hospital admission in select patients (eg, children who are ≥3 months old who are unable to tolerate oral therapy and are nontoxic appearing, well hydrated, without urologic abnormalities, and whose caretakers will be able to adhere to the outpatient regimen) [44-46].

Recent antibiotic exposure — Recent exposure to antibiotics, whether for treatment of an infection or as antimicrobial prophylaxis, is an important consideration in the choice of empiric antibiotic therapy [15,16,25,26,47-51]. Patients who have recently been treated with antibiotics are more likely to have a uropathogen that is resistant to that agent; pending culture and susceptibility results, they may require an antibiotic from a different class [26,52,53]. Antimicrobial prophylaxis for prevention of recurrent UTI is discussed separately. (See 'Prophylactic antibiotics' below and "Urinary tract infections in children: Long-term management and prevention", section on 'Antimicrobial prophylaxis'.)

Recurrent UTI — Review of the antimicrobial susceptibilities of the most recent urinary pathogens can be helpful in choosing empiric therapy for children with recurrent UTI.

Duration of therapy — In a systematic review, short-course antimicrobial therapy (two to four days) was as effective as standard duration (7 to 14 days) therapy in eradicating bacteria in children with suspected lower UTI (ie, afebrile children) [54]. In a retrospective cohort study, children hospitalized with UTI who had bacteremia more often received long-course (≥4 days) than short-course (<3 days) intravenous antibiotic treatment [55]. However, little evidence is available to guide duration of antimicrobial therapy in children with febrile UTIs. A multicenter trial, sponsored by the National Institutes of Health, is being conducted to determine the efficacy of short-course therapy for UTI in children [56]. If the trial demonstrates that short-course therapy is efficacious, clinicians may be able to limit the duration of exposure to antimicrobials to that needed to eradicate the offending uropathogen, reducing the likelihood of adverse events and the emergence of bacterial resistance.

In the meantime, we suggest a longer course of therapy for febrile children (usually 10 days) and a short course of therapy (three to five days) for immune-competent children presenting without fever.

Oral antibiotics can be used to complete the course of therapy for patients who are initially treated with parenteral antibiotics. We generally switch to oral antibiotics when the patient is tolerating oral fluids and has been afebrile for 24 hours. There is no minimum duration for parenteral therapy. In a retrospective cohort study of 3973 infants <60 days admitted to the hospital for parenteral therapy of UTI without bacteremia, duration of parenteral therapy was not associated with rate of readmission [57].

Response to therapy

Clinical response — The clinical condition of most patients improves within 24 to 48 hours of initiation of appropriate antimicrobial therapy [58].

The mean time to resolution of fever is 24 hours, but fever may persist beyond 48 hours [4]. In a review of 288 children younger than two years who were admitted to a tertiary-care children's hospital with febrile UTI, 89 percent were afebrile within 48 hours of antimicrobial therapy [58]. No differences were noted between those who remained febrile >48 hours and those who were afebrile within 48 hours with respect to bacteremia (10 and 8 percent, respectively), hydronephrosis (3 and 5 percent, respectively) and significant vesicoureteral reflux (VUR) (19 and 14 percent, respectively).

In children whose clinical condition (other than persistent fever) worsens or fails to improve as expected within 48 hours of initiation of antimicrobial therapy, broadening antimicrobial therapy may be indicated if the culture and sensitivity results are not yet available. As an example, most of the empiric regimens suggested above do not provide adequate coverage for Enterococcus, and the addition of ampicillin or amoxicillin may be warranted. (See 'Choice of agent' above.)

In addition, in children who worsen or fail to improve within 48 hours, renal and bladder ultrasonography should be performed as soon as possible (to evaluate the presence of a renal abscess or surgically correctable anatomic abnormalities or obstruction) [3,59,60]. (See 'Imaging' below.)

Repeat urine culture — Several observational studies suggest there is little utility in repeating the urine culture in children with UTI who are treated with an antibiotic to which their uropathogen is susceptible [58,61,62].

Accordingly, it is not necessary to routinely obtain repeat urine cultures during antimicrobial therapy to document sterilization of the urine, provided that the child has had the expected clinical response and the uropathogen is susceptible to the antibiotic that is used for treatment [63,64]. However, urine cultures should be performed after 48 hours of therapy if the patient fails to respond clinically or if the uropathogen is not susceptible (intermediate or resistant) to the antibiotic that is being used for treatment. It is important to routinely perform susceptibility testing on the isolated uropathogens to avoid unnecessary delay in administration of appropriate therapy.

Prophylactic antibiotics — Decisions regarding prophylactic antibiotics for children following initial febrile UTI should be made on a case-by-case basis.

●Antibiotic prophylaxis for children who have undergone voiding cystourethrogram (VCUG) and have documented VUR (of any grade) is discussed separately (see 'Voiding cystourethrogram'below and "Management of vesicoureteral reflux")

●For children who have undergone VCUG and do not have VUR or other renal/urologic abnormalities, but who had a severe or protracted course of illness or have risk factors for recurrence (eg, febrile seizures, prolonged hospitalization, renal abscess, single kidney, bladder and bowel dysfunction), and in whom prevention of any recurrence would be desirable, we discuss the risks and potential benefits of antimicrobial prophylaxis with families [65].

The 2011 AAP practice guideline (reaffirmed in 2016) does not recommend prophylactic antimicrobials following the first febrile UTI in children 2 to 24 months [3,66]. The United Kingdom's National Institute for Health and Care Excellence (NICE) guideline for UTI in children indicates that antibiotic prophylaxis should not be routinely recommended in infants and children following their first UTI but may be warranted after recurrent UTI [63]. (See "Urinary tract infections in children: Long-term management and prevention", section on 'Antimicrobial prophylaxis'.)



Content 3

Content 13

Content 11



USMLE Reviewer (Subscription Required)