Urinary tract infection (UTI) is one of the most common pediatric infections. It distresses the child, concerns the parents, and may cause permanent kidney damage. Occurrences of a first-time symptomatic UTI are highest in boys and girls during the first year of life and markedly decrease after that.
Febrile infants younger than 2 months constitute an important subset of children who may present with fever without a localizing source. The workup of fever in these infants should always include evaluation for UTI. The chart below details a treatment approach for febrile infants younger than 3 months who have a temperature higher than 38°C.
View Image | Application of low-risk criteria for and approach to the febrile infant: A reasonable approach for treating febrile infants younger than 2 months who .... |
Signs and symptoms
The history and clinical course of a UTI vary with the patient's age and the specific diagnosis. No one specific sign or symptom can be used to identify UTI in infants and children.
Children aged 0-2 months
Neonates and infants up to age 2 months who have pyelonephritis usually do not have symptoms localized to the urinary tract. UTI is discovered as part of an evaluation for neonatal sepsis. Neonates with UTI may display the following symptoms:
Infants and children aged 2 months to 2 years
Infants with UTI may display the following symptoms:
Children aged 2-6 years
Preschoolers with UTI can display the following symptoms:
Children older than 6 years and adolescents
School-aged children with UTI can display the following symptoms:
Physical examination findings in pediatric patients with UTI can be summarized as follows:
See Clinical Presentation for more detail.
The American Academy of Pediatrics (AAP) criteria for the diagnosis of UTI in children 2-24 months are the presence of pyuria and/or bacteriuria on urinalysis and of at least 50,000 colony-forming units (CFU) per mL of a uropathogen from the quantitative culture of a properly collected urine specimen.[3]
Urinalysis alone is not sufficient for diagnosing UTI. However, urinalysis can help in identifying febrile children who should receive antibacterial treatment while culture results from a properly collected urine specimen are pending.[4]
Urine specimen collection
Suprapubic aspiration is the method of choice for obtaining urine from the following patients:
Culture of a urine specimen from a sterile bag attached to the perineal area has a false-positive rate too high to be suitable for diagnosing UTI; however, a negative culture is strong evidence that UTI is absent.[3]
Laboratory studies
Imaging studies
Imaging studies are not indicated for infants and children with a first episode of cystitis or for those with a first febrile UTI who meet the following criteria:
If imaging studies of the urinary tract are warranted, they should not be obtained until the diagnosis of UTI is confirmed. Indications for renal and bladder ultrasonography are as follows:
Voiding cystourethrography (VCUG) may be indicated after a first febrile UTI if renal and bladder ultrasonography reveal hydronephrosis, scarring, obstructive uropathy, or masses or if complex medical conditions are associated with the UTI. VCUG is recommended after a second episode of febrile UTI.[3]
See Workup for more detail.
Patients with a nontoxic appearance may be treated with oral fluids and antibiotics. Outpatient care is reasonable if the following criteria are met:
Hospitalization is necessary for the following patients with UTI:
Treat febrile UTI as pyelonephritis, and consider parenteral antibiotics and hospital admission for these patients.
Antibiotics for parenteral treatment are as follows:
Patients aged 2 months to 2 years with a first febrile UTI
If clinical findings indicate that immediate antibiotic therapy is indicated, a urine specimen for urinalysis and culture should be obtained before treatment is started. Common choices for empiric oral treatment are as follows:
Children with cystitis
See Treatment and Medication for more detail.
Urinary tract infection (UTI) is one of the most common pediatric infections. It distresses the child, concerns the parents, and may cause permanent kidney damage. Prompt diagnosis and effective treatment of a febrile UTI may prevent acute discomfort and, in patients with recurrent infections, kidney damage. (See Presentation, DDx, Treatment, and Medication.)
The 2 broad clinical categories of UTI are pyelonephritis (upper UTI) and cystitis (lower UTI). The most common causative organisms are bowel flora, typically gram-negative rods. Escherichia coli is the organism that is most commonly isolated from pediatric patients with UTIs. However, other organisms that gain access to the urinary tract may cause infection, including fungi (Candida species) and viruses. (See Pathophysiology and Etiology.)
The febrile infant or child who has no other site of infection to explain the fever, even in the absence of systemic symptoms, should be assessed for the likelihood of pyelonephritis (upper UTI). Most episodes of UTI during the first year of life are pyelonephritis. (See DDx.)
Febrile infants younger than 2 months constitute an important subset of children who may present with fever without a localizing source. The workup of fever in these infants should always include evaluation for UTI. The chart below details a treatment approach for febrile infants younger than 3 months who have a temperature higher than 38°C. (See Presentation and DDx.)
View Image | Application of low-risk criteria for and approach to the febrile infant: A reasonable approach for treating febrile infants younger than 2 months who .... |
Children with UTIs who have voiding symptoms or dysuria, little or no fever, and no systemic symptoms, likely have cystitis. After age 2 years, UTI in the form of cystitis is common among girls.
In rare instances, UTI results in recognition of an important underlying structural or neurogenic abnormality of the urinary tract.[4] Some clinically significant urinary tract abnormalities may be identified using intrauterine ultrasonography. After birth, children with such abnormalities may incur additional kidney damage as a result of postnatal infection, but UTI is not the major cause of the kidney impairment.
Go to Urinary Tract Infection in Males and Cystitis in Females for complete information on these topics. For patient education information, see Urinary Tract Infections (UTIs) and Bladder Control Problems.
Typically, UTIs develop when uropathogens that have colonized the periurethral area ascend to the bladder via the urethra. From the bladder, pathogens can spread up the urinary tract to the kidneys (pyelonephritis) and possibly to the bloodstream (bacteremia). Poor containment of infection, including bacteremia, is more often seen in infants younger than 2 months.
Urine in the proximal urethra and urinary bladder is normally sterile. Entry of bacteria into the urinary bladder can result from turbulent flow during normal voiding, voiding dysfunction, or catheterization. In addition, sexual intercourse or genital manipulation may foster the entry of bacteria into the urinary bladder. More rarely, the urinary tract may be colonized during systemic bacteremia (sepsis); this usually happens in infancy. Pathogens can also infect the urinary tract through direct spread via the fecal-perineal-urethral route.
Bacterial infections are the most common cause of UTI, with E coli being the most frequent pathogen, causing 75-90% of UTIs. Other bacterial sources of UTI include the following:
Fungi (Candida species) may also cause UTIs, especially after instrumentation of the urinary tract. Adenovirus is a rare cause of UTI and may cause hemorrhagic cystitis.
Deregulation of candidate genes may predispose patients to recurrent UTIs. The identification of a genetic component may allow the identification of at-risk individuals and, therefore, prediction of the risk of recurrent UTI in their offspring.[5] Genes that are possibly responsible for susceptibility to recurrent UTIs include HSPA1B, CXCR1, CXCR2, TLR2, TLR4, and TGFβ1.[5]
Susceptibility to UTI may be increased by any of the following factors:
Children who receive antibiotics (eg, amoxicillin, cephalexin) for other infections are at increased risk for UTI. These agents may alter gastrointestinal (GI) and periurethral flora, disturbing the urinary tract's natural defense against colonization by pathogenic bacteria.
Prolonged retention of urine may permit incubation of bacteria in the bladder. Voiding dysfunction is not usually encountered in a child without neurogenic or anatomic abnormality of the bladder until the child is in the process of achieving daytime urinary control.
A child with uninhibited detrusor contractions may attempt to prevent incontinence during a detrusor contraction by increasing outlet resistance. This may be achieved by using various posturing maneuvers, such as tightening of the pelvic-floor muscles, applying direct pressure to the urethra with the hands, or performing the Vincent curtsy, which consists squatting on the floor and pressing the heel of one foot against the urethra. As a result, bacteria-laden urine in the distal urethra may be milked back into the urinary bladder (urethrovesical reflux).
Constipation, with the rectum chronically dilated by feces, is an important cause of voiding dysfunction. Neurogenic or anatomic abnormalities of the urinary bladder may also cause voiding dysfunction.
Voiding dysfunction should be evaluated and managed appropriately. Surgical correction of underlying anatomic disorders may be indicated in select cases. For more information, see Pediatric Vesicoureteral Reflux.
For male infants, neonatal circumcision substantially decreases the risk of UTI. Schoen et al found that during the first year of life, the rate of UTI was 2.15% in uncircumcised boys, versus 0.22% in circumcised boys.[6] Risk is particularly high during the first 3 months of life; Schaikh et al reported that in febrile boys younger than 3 months, UTI was present in 2.4% of circumcised boys and in 20.1% of uncircumcised boys.[7]
The incidence of UTIs varies based on age, sex, and gender. Overall, UTIs are estimated to affect 2.4-2.8% of children in the United States annually.
Occurrences of first-time, symptomatic UTIs are highest in boys and girls during the first year of life and markedly decrease after that. Shaikh et al found that the overall prevalence of UTI in infants presenting with fever was 7.0%.[6] By age, the rates in girls were as follows:
In febrile boys less than 3 months of age, 2.4% of circumcised boys and 20.1% of uncircumcised boys had a UTI.[6]
During the first few months of life, the incidence of UTI in boys exceeds that in girls. By the end of the first year and thereafter, first-time and recurrent UTIs are most common in girls. The incidence of UTI in children aged 1-2 years is 8.1% in girls and 1.9% in boys.
Studies from Sweden have indicated that at least 3% of girls and 1% of boys have a symptomatic UTI by age 11 years. Other data, however, have suggested that 8% of girls have a symptomatic UTI during childhood and that the incidence of a first-time UTI in boys older than 2 years is probably less than 0.5%. In sexually active teenage girls, the incidence of UTIs approaches 10%.
In studies by Hoberman et al, the prevalence of febrile UTIs in white infants exceeded that in black infants.[8] These investigators found that among white female infants younger than 1 year who had a temperature of 39°C or more and were seen in an emergency department, 17% had UTI.
Mortality related to UTI is exceedingly rare in otherwise healthy children in developed countries.
Cystitis may cause voiding symptoms and require antibiotics, but it is not associated with long-term, deleterious kidney damage. The voiding symptoms are usually transient, clearing within 24-48 hours of effective treatment.
Morbidity associated with pyelonephritis is characterized by systemic symptoms, such as fever, abdominal pain, vomiting, and dehydration. Bacteremia and clinical sepsis may occur.[9]
Children with pyelonephritis may develop focal inflammation of the kidney (focal pyelonephritis) or renal abscess. Any inflammation of the renal parenchyma may lead to scar formation. Approximately 10-30% of children with UTI develop some renal scarring; however, the degree of scarring required for the development of long-term sequelae is unknown.
Long-term complications of pyelonephritis are hypertension, impaired renal function, and end-stage renal disease.
Dehydration is the most common acute complication of UTI in the pediatric population. Intravenous fluid replacement is necessary in more severe cases.
In developed countries, kidney damage with long-term complications as a consequence of UTI has become less common than it was in the early 20th century, when pyelonephritis was a frequent cause of hypertension and end-stage renal disease in young women. This change is probably a result of improved overall healthcare and close follow-up of children after an episode of pyelonephritis. Currently, these complications are most commonly encountered in infants with congenital renal damage.[10, 11]
The history and clinical course of a urinary tract infection (UTI) vary with the patient's age and the specific diagnosis. No one specific sign or symptom can be used to identify UTI in infants and children.
Combinations of findings, including a prior history of UTI, circumcision in boys, and, in older children, typical symptoms such as frequency, abdominal or suprapubic discomfort, and dysuria, should be taken into account when making a decision to evaluate for UTI.[12, 13] Guidelines from the American Academy of Pediatrics recommend considering the diagnosis of UTI in patients aged 2 months to 2 years with unexplained fever.[14]
When UTI is diagnosed in a child, an attempt should be made to identify any risk factors for the UTI. These include recent broad-spectrum antibiotic therapy, an anatomic anomaly, voiding dysfunction, and constipation.
Neonates and infants up to age 2 months who have pyelonephritis usually do not have symptoms localized to the urinary tract. UTI is discovered as part of an evaluation for neonatal sepsis.
Neonates with UTI may display the following symptoms:
Infants with UTI may display the following symptoms:
As with young infants, the majority of infants and young children in this age range who have pyelonephritis also lack symptoms localized to the urinary tract. However, some children aged 1-2 years may present with voiding symptoms suggestive of cystitis, with crying on urination or only a foul odor to the urine in the absence of clinically significant fever (temperature < 38°C).
Infants and young children of this age may also have only a history of unexplained fever (ie, rectal or tympanic membrane temperature of >38°C). Some infants with pyelonephritis in this age range have fever and few other symptoms, whereas others are acutely ill and have a history of irritability, decreased oral intake, abdominal pain, vomiting, and loose bowel movements. Patients in this age group are at higher risk for renal injury than are older children, possibly because the lack of localizing signs of infection delays the start of antibiotic therapy.
Preschoolers with UTI can display the following symptoms:
Children in this age group with febrile UTI (pyelonephritis) usually have systemic symptoms with loss of appetite, irritability, and abdominal, flank, or back pain. Voiding symptoms may be present or absent.
Children with acute cystitis have voiding symptoms with little or no temperature elevation. Voiding dysfunction may include urgency, frequency, hesitancy, dysuria, or urinary incontinence. Suprapubic or abdominal pain may be present, and the urine sometimes has a strong or foul odor.
School-aged children with UTI can display the following symptoms:
Adolescents are more likely to present with typical urinary symptoms (eg, dysuria, urgency, frequency). Adolescent girls with vaginitis or a sexually transmitted infection (STI) may present with similar symptoms. In addition, adolescent girls who are diagnosed with cystitis may have a concurrent vaginitis or STI.[15]
UTI among children in this age range usually affects the lower tract, but pyelonephritis also occurs. Symptoms are similar to those in children aged 2-6 years.
Girls who have pyelonephritis in infancy or early childhood, including those with persistence of vesicoureteral reflux (VUR), usually have cystitis with UTI when they are older. They are also prone to have a recurrence during pregnancy.
Infants and younger children with pyelonephritis usually have no localizing findings, but they are febrile and often irritable. Older children with pyelonephritis often have tenderness of the flank or costovertebral angle, and those with cystitis may have suprapubic tenderness. Hypertension should raise suspicion of hydronephrosis or renal parenchyma disease.
Physical examination findings in pediatric patients with UTI can be summarized as follows:
Examine the external genitalia for signs of irritation, pinworms, vaginitis, trauma, or sexual abuse.
The American Academy of Pediatrics (AAP) criteria for the diagnosis of urinary tract infection (UTI) in children 2-24 months are the presence of pyuria and/or bacteriuria on urinalysis and the presence of at least 50,000 colony-forming units (CFU) per mL of a uropathogen from the quantitative culture of a properly collected urine specimen. In neonates younger than 2 months of age, criteria include the presence of lower amounts of a single pathogen (10,000-50,000 CFU/mL).[3]
Due to concerns over urinalysis sensitivity in young infants, a study collected urinalysis results on a cross-sectional sample of 276 infants < 3 months of age with bacteremic UTI from 11 hospital systems. The study concluded that in young infants with bacteremic UTI, urinalysis sensitivity in infants with UTI in general is higher than what has been previously reported.[16]
A midstream, clean-catch specimen may be obtained from children who have urinary control. In the infant or child unable to void on request, the specimen for culture should be obtained by suprapubic aspiration or urethral catheterization.
Suprapubic aspiration is also the method of choice for obtaining urine from uncircumcised boys with a redundant or tight foreskin, from girls with tight labial adhesions, and from children of either sex with clinically significant periurethral irritation.
Culture of a urine specimen from a sterile bag attached to the perineal area has a false-positive rate so high that this method of urine collection is not suitable for diagnosing UTI. However, a culture of a urine specimen from a sterile bag that shows no growth is strong evidence that UTI is absent.[3]
In a study of 6394 febrile infants aged 1-90 days, Glissmeyer and colleagues found evidence that urine dipstick testing alone may provide an adequate initial UTI screen, comparing well in terms of positive predictive value and specificity with urine microscopy alone or both tests combined.[17, 18] UTI was diagnosed in 770 (12%) of the study’s infants. Although the different screens each had a negative predictive value of more than 98%, the dipstick screen had a higher positive predictive value (66.8%) than did the combined test (51.2%) or microscopy alone (58.6%).[17, 18]
The dipstick test by itself also had a higher specificity (93.8%) compared with the combined test (87.6%) or microscopy (91.3%), although it did have a lower sensitivity than the combined test (90.8% vs 94.7%, respectively.)[17, 18]
Urinalysis alone is not sufficient for diagnosing UTI. Children with unexplained fever or voiding symptoms may have positive urinary cultures even when abnormal findings are not evident on dipstick testing and complete urinalysis.[19, 20, 21, 22, 23, 24, 25] However, urinalysis can help in identifying febrile children who should receive antibacterial treatment while culture results from a properly collected urine specimen are pending.[26]
A study by Lunn et al supports the use of automated microscopy for screening urine samples for culture in children.[27] In 280 urine samples collected from 263 pediatric patients, automated microscopy performed comparably to urine dipstick testing in the diagnosis of UTI; automated microscopy had better specificity and likelihood ratios than dipstick testing, but it had slightly lower sensitivity.
Hematologic studies do not tend to help in the diagnosis of UTIs, although they should be obtained in patients who appear ill. Obtain a complete blood count (CBC) and basic metabolic panel for children with a presumptive diagnosis of pyelonephritis. Perform blood cultures in febrile infants and older patients who are clinically ill, toxic, or severely febrile.
Renal function can be measured by serum creatinine and blood urea nitrogen (BUN) levels; both may be elevated in severe disease. Electrolyte abnormalities may be present. Procalcitonin, a propeptide of calcitonin that has been found to be elevated in response to bacterial endotoxins, has shown promise in helping to diagnose pyelonephritis and early renal damage.[28, 29, 30]
Imaging studies are not indicated for infants and children with a first episode of cystitis or for those with a first febrile UTI who meet the following criteria:
If imaging studies of the urinary tract are warranted, they should not be obtained until the diagnosis of UTI is confirmed. Febrile infants aged 2-24 months with UTIs should undergo renal and bladder ultrasonography.[3] Other indications for ultrasonography of the urinary tract after a febrile UTI in pediatric patients are as follows:
Finally, renal ultrasonography should be considered for any child with a first febrile UTI in whom good follow-up cannot be ensured.
Performance of voiding cystourethrography (VCUG) after a first febrile UTI may be indicated if renal and bladder ultrasonography reveal hydronephrosis, scarring, obstructive uropathy, or masses or if complex medical conditions are associated with the UTI. Informed consent and preferences of the patient’s parents or caregivers are considered.
Children who respond to treatment for a UTI but afterwards demonstrate an abnormal voiding pattern may need to undergo an evaluation for voiding dysfunction. This evaluation may include standard VCUG.
VCUG is also recommended after a second episode of febrile UTI.[3] There is some concern, however, that without VCUG after the first documented febrile UTI, some cases of significant reflux disease will be missed.[31]
The chart below details a management approach to febrile infants younger than 3 months with a temperature of more than 38°C.
View Image | Application of low-risk criteria for and approach to the febrile infant: A reasonable approach for treating febrile infants younger than 2 months who .... |
Go to Urinary Tract Infection in Males, Cystitis in Females, and Radiographic Evaluation of the Pediatric Urinary Tract for complete information on these topics.
The criterion standard for obtaining urine specimens for culture in pediatric patients is suprapubic aspiration.[32] However, catheterization is the most commonly used technique in infants and younger children. Midstream clean-catch urine specimens are adequate for older children who can provide them. The presence of at least 50,000 CFU/mL of a uropathogen is the AAP definition for a UTI.[3]
Culture of a urine specimen from a sterile bag attached to the perineal area has a false-positive rate so high that this method of urine collection is not suitable for diagnosing UTI. However, a culture of a urine specimen from a sterile bag that shows no growth is strong evidence that UTI is absent.[3]
Along with a positive urine culture, urinalysis showing pyuria and/or bacteriuria is part of the criterion standard for the diagnosis of UTIs.[3] Positive dipstick readings for nitrite, leukocyte esterase, or blood may also suggest a UTI. Dipstick tests have sensitivities of approximately 85-90%. Microscopic examination of spun urine can evaluate for the presence of white blood cells (WBCs), red blood cells (RBCs), bacteria, casts, and skin contamination (eg, epithelial cells).
On a suprapubic aspirate, the presence of 5 or more WBCs per high-power field suggests an infection. The presence of 10 or more WBC/μL is also consistent with infection.[33, 34] Gram stain of unspun urine may reveal organisms. A hemacytometer measures cells per volume and has been found to be more sensitive and specific than standard microscopic examination.[33, 34] The combination of hemacytometer cell count and Gram stain has been shown in studies to have a sensitivity approaching 95%.
Approximately 10-20% of pediatric patients with UTIs have normal urinalysis results. Multiple organisms may be present in patients with structural abnormalities.
A study by Tzimenatos et al that included an analysis of data from 4147 febrile infants ≤60 days old reported that for the 289 infants with a UTI and colony counts ≥50 000 CFUs/mL, a positive urinalysis regardless of bacteremia showed sensitivities of 0.94; 1.00 with bacteremia; and 0.94 without bacteremia. Specificity in all groups was 0.91.[63]
Methods of urine collection and examination, as well as salient findings, are shown in Tables 1 and 2, below.
Table 1. Urinalysis for Presumptive Diagnosis of Urinary Tract Infection*
View Table | See Table |
Table 2. Quantitative Urine Culture for the Diagnosis of Urinary Tract Infection*
View Table | See Table |
In a large retrospective analysis of children with UTI, laboratory-based urinalysis was more sensitive than point-of-care urinalysis in diagnosing pediatric UTI. Point-of-care urinalysis had 82.5% sensitivity, 81.3% specificity, 33.9% positive predictive value, and 97.6% negative predictive value, whereas laboratory-based urinalysis had 89.1% sensitivity and a significantly higher negative predictive value (98.9%). Laboratory-based urinalysis, however, was less specific (76.1%) and had a lower positive predictive value (22.7%).[35, 36]
Ultrasonography of the urinary tract has replaced intravenous pyelography (IVP) as the imaging study of choice in children with UTI. The AAP Clinical Practice Guidelines recommend routine ultrasonography of the urinary tract after a first febrile UTI in children aged 2-24 months.[3] Ultrasonography in these cases seldom provides information that changes management, however.
The clinician's judgment should guide the decision regarding imaging studies, rather than a rigid rule. Urinary ultrasonography is safe, noninvasive study, and easy to perform. It is useful in excluding obstructive uropathy, as well as in identifying a solitary or ectopic kidney and, in some cases, moderate renal damage caused by pyelonephritis.
A study by Shaikh et al indicates that in children and adolescents with a first UTI, the risk of scarring is doubled in those with either an abnormal renal ultrasonographic finding or with both a fever of 39°C (102°F) or above and a causative organism other than Escherichia coli. The investigators found the predictive ability of a model based on these factors to be only 3-5% below that obtainable with models in which a blood draw and/or a voiding cystourethrogram (VCUG) are needed. The report was a meta-analysis of nine cohort studies, and included 1280 patients aged 18 years or younger.[1, 2] The study also indicated that the greatest risk factor for renal scarring is the presence of grade IV or V vesicoureteral reflux (VUR). Of the 199 patients in the study who had renal scarring, 100 had VUR, although only 4.1% of the 1280 patients had grade IV or V type.
Traditionally, VCUG has been recommended for infants and children after a first febrile UTI. This is based on assumptions that most upper UTIs occur because of urinary bladder infection and that vesicoureteral reflux (VUR) transfers bacteria in the bladder to the kidney. However, scintigraphic studies have shown that many children with pyelonephritis have no evidence of VUR.[3, 37]
VCUG is indicated if renal and bladder ultrasonography reveals hydronephrosis, scarring, or other findings that suggest either high-grade VUR or obstructive uropathy. VCUG should also be performed if a patient has a recurrence of a febrile UTI, even if previous ultrasonographic examination findings were unremarkable.[3]
In theory, VCUG results could guide the use of antibacterial prophylaxis. However, data do not support the use of prophylaxis to prevent recurrent febrile UTI in infants with no VUR or with grade 1-4 VUR.[38] Consequently, the AAP no longer recommends the routine use of VCUG after the first UTI.[3]
This topic remains controversial. More definitive evidence on the benefit of antibiotic prophylaxis in children with VUR—and thus on the indications for VCUG in pediatric patients with UTI—is anticipated from the Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) study, which is ongoing.[39]
Some clinicians recommend waiting 4-6 weeks after febrile UTI is treated to perform VCUG. If the child is given suppressive antibacterial treatment during this period, this recommendation is acceptable. However, studies have shown that the VCUG may be obtained within the first few days of treating febrile UTI if the voiding pattern has returned to its pre-UTI state.[40, 41, 42]
Prehospital care is rarely a concern in patients with urinary tract infection (UTI). However, patients who are uroseptic and in shock may present via emergency medical services (EMS), in which case, standard supportive measures for septic patients should be followed.
Patients with a nontoxic appearance may be treated with oral fluids and antibiotics. Toxic-appearing patients must be aggressively treated with intravenous (IV) fluids and parenteral antibiotics.
Most cases of uncomplicated UTI respond readily to outpatient antibiotic treatments without further sequelae. Antibiotic resistance among uropathogens is increasing dramatically, however. Previous antibiotic exposure (ie, for otitis media) has been found to be associated with drug-resistant UTIs and should be kept in mind when choosing empiric therapy.[43]
The choice of outpatient versus inpatient care can often be guided by practical considerations. Outpatient care is reasonable if the following criteria are met:
A Cochrane review concluded that children with acute pyelonephritis can be treated effectively with either oral antibiotics or with 2-4 days of IV therapy followed by oral therapy.[44] Similarly, a study by Hoberman et al indicated that oral therapy with a third-generation cephalosporin was as effective as traditional inpatient parenteral treatment.[45]
For parenteral therapy in a patient who is not allergic to cephalosporins, initial treatment may consist of a single dose of ceftriaxone (75 mg/kg IV/IM q12-24h). If the patient has cephalosporin allergy, initial treatment may be with gentamicin (2.5 mg/kg IV/IM as a single dose). Patients who demonstrate a satisfactory response can be switched to an oral antibacterial agent at therapeutic doses within the next 12-18 hours.
Arrange for a follow-up (which is usually performed by telephone) at 24 hours to monitor the patient's response to treatment and at 48 hours to modify treatment if the results of antibacterial sensitivity studies indicate a need to change. Arrange for a follow-up visit after 7-10 days to check the patient's clinical course.
Appropriate treatment, imaging to identify correctable anatomic abnormalities, and follow-up can help prevent long-term sequelae in patients with more severe cases or chronic, recurrent infections.[3] All patients should have close follow-up to evaluate response to antibiotics. Repeat urinalysis and/or urine cultures are not needed if the patient's condition responds to therapy as expected.
The American Academy of Pediatrics (AAP) recommends that all infants and young children (aged 2 mo to 2 y) with a first UTI undergo urinary tract ultrasonography; depending on the result, this may be followed by voiding cystourethrography (VCUG).[3] These studies should be performed promptly if patients fail to show expected clinical response within 2 days of treatment.
VCUG may detect vesicoureteric reflux (VUR). Low-grade VUR (grade 1-2) usually resolves without permanent damage, but high-grade (grade 4-5) VUR may require surgical correction.
Go to the following Medscape Reference articles for further information on these topics:
Hospitalization is necessary for the following patients with UTI:
Treat febrile UTI as pyelonephritis, and consider parenteral antibiotics and hospital admission for these patients.
The diagnosis in infants younger than age 8 weeks with a febrile UTI is usually based on fever and on positive results from a urine specimen obtained by catheterization. In this age 10,000 colonies/mm3 defines bacteriuria. Infants with such findings are usually hospitalized and receive parenteral antibiotic therapy (see Table 3, below). However, clinical judgment may indicate that home treatment is appropriate. Parenteral antibiotics may be used with daily follow-up until the patient is afebrile for 24 hours. Complete 10-14 days of therapy with an oral antibiotic that is active against the infecting bacteria.
Table 3. Antibiotic Agents for Parenteral Treatment of a Urinary Tract Infection
View Table | See Table |
A retrospective review of more than 1500 babies aged 29-60 days with fever and culture-proven UTIs found that infants without a high-risk medical history who were not clinically ill on presentation to an emergency department (ED) and had low-risk laboratory values were at low risk overall for bacteremia and serious adverse events, such as meningitis or the need for intensive care unit (ICU) support.[46] Infants in this age group who meet this criteria can be considered for briefer hospitalization and close outpatient management. If the medical history raises concern, however, these infants should be treated as younger infants are (ie, those aged 0-28 days).[46]
If clinical findings indicate that immediate antibiotic therapy is indicated, a urine specimen for urinalysis and culture should be obtained before treatment is started. Specimens may be collected by means of suprapubic aspiration or catheterization.
A study by Shaikh et al analyzed data for 482 children (age, 2 - 72 months) with a first or second UTI to determine whether delay in the initiation of antimicrobial therapy for febrile UTIs is associated with the occurrence and severity of renal scarring. The study found that a total of 35 children (7.2%) developed new renal scarring and that this renal scarring was significantly associated with a delay in the initiation of antimicrobial therapy.[47, 48]
According to AAP guidelines for the treatment of initial UTIs in febrile infants and children aged 2-24 months old, antibiotics can be given orally or parenterally, with the choice of route based on practical considerations.[3] Oral antibiotics should not be used in a child who is acutely ill or toxic, has persistent vomiting, or has moderate to severe dehydration. Daily follow-up and good compliance are essential with this approach.
The AAP recommends basing the choice of antibiotic on local sensitivity patterns, if known. The choice can be adjusted, if necessary, when results of sensitivity testing become available. Antibiotics can be given for 7 or 14 days.[3]
Common choices for empiric oral treatment are a second- or third-generation cephalosporin, amoxicillin/clavulanate, or sulfamethoxazole-trimethoprim (SMZ-TMP). (See Table 4, below). A Canadian retrospective chart review of 173 pediatric patients diagnosed with a clinical UTI found that if the urinalysis is positive for nitrites, 1.4% of pathogens were resistant to third-generation cephalosporin, and 8.4% were resistant to first-generation cephalosporins.[49]
Table 4. Antibiotic Agents for the Oral Treatment of Urinary Tract Infection
View Table | See Table |
The AAP guidelines for the followup of these patients can be summarized as follows[3] :
Pyelonephritis is considered complicated when it occurs in a neonate or an infant, in a patient with an anatomic abnormality of the urinary tract or abnormal renal function, or in a patient who is immunocompromised.
Provide appropriate IV fluids, usually at 1-1.5 times the usual maintenance rate. Parenteral treatment with a third-generation cephalosporin (eg, ceftriaxone, cefotaxime) is appropriate initial empiric coverage for a complicated UTI and pyelonephritis to cover for ampicillin-resistant, gram-negative pathogens (see Table 3). Add ampicillin if gram-positive cocci are present in the urinary sediment or if no organisms are observed.
Gentamicin is an alternative empiric choice and may be considered in patients with cephalosporin allergy. Monitor renal function and blood aminoglycoside levels if this medication is required for more than 48 hours.
Results of urine culture and sensitivity studies are usually available within 48 hours. If the pathogen is sensitive to the antibiotic used and the child is improving, continue treatment via the parenteral route until the child has been afebrile for 24-36 hours, has improved clinically, and is able to retain oral medications. An oral antibiotic that is effective against the infecting organism may then be substituted for parenteral therapy (see Table 4).
The hospitalized patient is usually ready to go home after 48-72 hours. Continue therapeutic doses of antibiotics for a total of 10-14 days of antibiotic therapy. Antibiotic prophylaxis can be considered (see Table 5); if chosen, it should continue until a VCUG is obtained, if one is to be performed.
Children with cystitis usually do not require special medical care other than appropriate antibiotic therapy and symptomatic treatment if voiding symptoms are marked. Antibiotic therapy is started on the basis of the practitioner's appraisal of the patient's clinical history and urinalysis results before the diagnosis is documented.
A 4-day course of an oral antibiotic agent is recommended for the treatment of cystitis (see Table 4). A systematic review of treatments for cystitis in children showed no difference in efficacy with 7-14 days of therapy compared with 2-4 days.[26] Single-dose or single-day therapy is not recommended in children with cystitis. If the clinical response is not satisfactory after 2-3 days, alter therapy on the basis of antibiotic susceptibility.
Symptomatic relief for dysuria is accomplished by increasing fluid intake to enhance urine dilution and output and with the use of acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs). If voiding symptoms are severe and persistent, add phenazopyridine hydrochloride (Pyridium). Do not administer phenazopyridine for longer than 48 hours, because of the risk of methemoglobinemia, hemolytic anemia, and other adverse reactions. Sitting in a tub of warm water for 20-30 minutes 3-4 times daily also often affords symptomatic relief.
Many studies have failed to show reductions in the incidence of recurrent UTIs with the use of antibiotic prophylaxis. Several of those studies, however, did not have sufficient statistical power to detect differences or did not have stringent definitions of UTI and inclusion criteria.[50, 51, 52, 53, 54]
A study that evaluated 12 months of prophylaxis with sulfamethoxazole-trimethoprim (SMZ-TMP) compared with placebo to prevent UTI showed a small, but statistically significant, reduction in incidence but did not show any difference in renal scarring. In addition, a significant increase in UTI with SMZ-TMP ̶ resistant organisms occurred in the treatment group.[55] A meta-analysis that reviewed seven randomized controlled trials that included 1427 febrile UTI patients also found no effect of antibiotic prophylaxis in preventing renal scarring.[62]
A meta-analysis of a selected subset of high-quality, randomized, controlled trials concluded that long-term antibiotics reduce the risk of more symptomatic infections. The benefit is small, however, and must be weighed against the likelihood that future infections may be with bacteria that are resistant to the antibiotic administered.[56]
A study by Selekman et al reported that patients with a history of vesicoureteral reflux being treated with continuous antibiotic prophylaxis were more likely to have a multidrug-resistant urinary tract infection (33% in the antibiotic prophylaxis group vs 6% in the placebo or no treatment group).[64]
Until evidence-based guidelines about the use of suppressive antibacterial therapy after an initial febrile UTI are available, use of antibiotic prophylaxis is based on expert opinion. Antibiotic prophylaxis is more often recommended for children with high-grade reflux (grade 3-5). The current AAP guidelines do not recommend prophylactic antibiotics to prevent UTI recurrences (see table 5, below).[3]
Table 5. Antibiotic Agents to Prevent Reinfection
View Table | See Table |
Parents of children with a history of UTI should also be advised to avoid unnecessary use of antibiotics for upper respiratory infections and otitis media. Antibiotics can alter GI and periurethral flora and compromise natural defenses against colonization by pathogenic agents.
Consider circumcision of male neonates. The AAP policy statement on circumcision is that “the health benefits of newborn male circumcision outweigh the risks and that the procedure's benefits justify access to this procedure for families who choose it.”[57] The AAP notes that the benefits of the procedure include prevention of UTIs.[57]
A study by Ferrara et al investigating the effect of daily cranberry juice (50 mL) in girls aged 3-14 years with recurrent UTIs found that consumption of concentrated cranberry juice on a daily basis appeared to prevent symptomatic UTI recurrence in children.[58] In this study, the use of a drink containing Lactobacillus strain GG did not prevent UTI.
A systematic review of studies of cranberry products used for the prevention of UTIs showed a small, possible benefit for women with recurrent UTI, but the evidence was not statistically significant. Also, in contrast to the Ferrara study, the review did not find that cranberry products significantly reduced UTI recurrence in children.[59]
Consultation with a urologist is not typically required at presentation in pediatric patients with an initial febrile UTI, unless obstruction of the urinary tract is evident. However, patients with VUR of grade 4 or worse should be referred to a pediatric nephrologist or urologist. Consultation with an infectious disease specialist may be useful if there is reason to suspect infection with an unusual organism or one that is antibiotic resistant.
Antibiotics are used to treat urinary tract infection (UTI) and, in select patients, to prevent recurrence. Avoid nephrotoxic drugs whenever possible. On occasion, analgesic therapy may be used to provide relief because of voiding symptoms.
Start antibiotics after performing urinalysis and obtaining a urine specimen for culture in patients with UTI. A 7- to 10-day course of antibiotics is recommended, even for an uncomplicated infection. Short-course treatments should be reserved for nontoxic-appearing adolescent girls with UTI. Be aware of increasing rates of antibiotic resistance and the need to choose antibiotic therapy accordingly.
Empiric antibiotics should be chosen for coverage of the most common uropathogens, namely Escherichia coli and Enterococcus, Proteus, and Klebsiella species. Oral antibiotics are adequate therapy for febrile UTIs in young infants and children.
The possibility of antibiotic resistance must be considered when choosing empiric therapy, especially with ampicillin. Knowledge of the local antibiotic resistance helps in guiding antibiotic choice.
A study by Bryce et al that reviewed studies investigating the prevalence of antibiotic resistance in UTI caused by E. coli in children found that the prevalence of resistance is high, particularly in countries outside the Organization for Economic Co-operation and Development (OECD). Resistance in countries outside the OECD was: 79.8% for ampicillin, 60.3% for co-amoxiclav, 26.8% for ciprofloxacin, and 17.0% for nitrofurantoin.[60]
In a study of 607 children with reflux diagnosed by VCUG after a first or second UTI, the subjects were randomized to antibiotic prophylaxis with TMP-SMX or placebo. The risk of recurrences was reduced by 50% in the treatment group (hazard ratio, 0.50; 95% CI, 0.34-0.74). The risk of renal scarring overall did not differ significantly between the groups over 2 years. Also, the occurrence of a subsequent UTI with a TMP-SMX — resistant organism was significantly increased in the treatment group. The children enrolled were aged 2-71 months, a wider age range than the AAP guidelines currently encompass.[61]
Clinical Context: This third-generation cephalosporin is used for initial parenteral therapy for complicated pyelonephritis in pediatric patients beyond the neonatal period. It is indicated for urinary tract infections caused by E coli, Proteus mirabilis, Morganella morganii, P vulgaris, or K pneumoniae.
Clinical Context: Cefotaxime is a third-generation cephalosporin that is used as initial parenteral therapy for pediatric patients with acute complicated pyelonephritis. It may be used in neonates or jaundiced patients. Dosing every 6-8 hours is required. In infants, a 2- to 8-week regimen also includes ampicillin.
Clinical Context: Ampicillin is a parenteral agent used for initial treatment of patients with acute pyelonephritis who have gram-positive cocci in urinary sediment or in whom no organisms are observed in the urine. It is indicated for UTIs caused by E coli and P mirabilis.
Clinical Context: This is an oral therapy for infection with susceptible organisms. Amoxicillin inhibits bacterial cell-wall synthesis by binding to penicillin-binding proteins. The addition of clavulanate inhibits beta-lactamase ̶ producing bacteria.
This is a good alternative antibiotic for patients who are allergic to or intolerant of the macrolide class. It is usually well tolerated and is effective against most infectious agents, although it is not effective against Mycoplasma and Legionella species. It has good tissue penetration but does not enter the cerebrospinal fluid (CSF).
For patients over age 3 months, base dosing protocol on amoxicillin content. Because of different amoxicillin/clavulanic acid ratios in the 250-mg tablet (250/125) versus the 250-mg chewable tablet (250/62.5), do not use the 250-mg tablet until the child weighs over 40 kg. The amoxicillin-clavulanate combination is also available as an oral suspension for children. The half-life of the oral form is 1-1.3 hours.
Clinical Context: This aminoglycoside is used for initial parenteral therapy in patients with bacterial pyelonephritis who are allergic to cephalosporins. For complicated UTI, it is sometimes used in combination with a cephalosporin.
Clinical Context: This is an oral treatment for bacterial UTI and for prevention of reinfection. It is available as an oral tablet or a suspension.
Clinical Context: Cephalexin is a first-generation cephalosporin. This is an oral treatment for bacterial UTI and for prevention of infection in infants younger than 6-8 weeks.
Clinical Context: Cefixime is a third-generation cephalosporin used for oral treatment of acute bacterial UTI. By binding to 1 or more penicillin-binding proteins, it arrests bacterial cell-wall synthesis and inhibits bacterial growth.
Clinical Context: Indicated for complicated urinary tract infections (cUTIs) including pyelonephritis in adult and pediatric patients aged 3 months or older caused by the following susceptible Gram-negative microorganisms: Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Citrobacter freundii complex, Proteus mirabilis, and Pseudomonas aeruginosa.
Clinical Context: Cefpodoxime is a third-generation cephalosporin used for oral treatment of acute bacterial UTI. It is indicated for the management of infections caused by susceptible mixed aerobic-anaerobic microorganisms.
Clinical Context: This is an oral treatment for bacterial infections of the lower urinary tract (cystitis) and for the prevention of reinfection. Nitrofurantoin is a synthetic nitrofuran that interferes with bacterial carbohydrate metabolism by inhibiting acetylcoenzyme A. It is bacteriostatic at low concentrations (5-10 mcg/mL) and is bactericidal at higher concentrations.
Clinical Context: Trimethoprim is an oral antibiotic used for the prevention of urinary tract infection. It is a dihydrofolate reductase inhibitor that prevents the production of tetrahydrofolic acid in bacteria. It is active in vitro against a broad range of gram-positive and gram-negative bacteria, including uropathogens (eg, Enterobacteriaceae and Staphylococcus saprophyticus).
Resistance is usually mediated by decreased cell permeability or by alterations in the structure or amount of dihydrofolate reductase. Trimethoprim demonstrates synergy with sulfonamides, potentiating inhibition of bacterial tetrahydrofolate production.
Clinical Context: This agent is a fluoroquinolone that inhibits bacterial DNA synthesis and, consequently, growth by inhibiting DNA gyrase and topoisomerases, enzymes that are required for the replication, transcription, and translation of genetic material. Quinolones have broad activity against gram-positive and gram-negative aerobic organisms. Ciprofloxacin has no activity against anaerobes. Continue treatment for at least 2 days (7-14 days typical) after signs and symptoms have disappeared.
This agent is not a drug of first choice in pediatric patients, because of an increased incidence of adverse events, including arthropathy, compared with controls. No data exist for dose adjustments for pediatric patients with renal impairment.
Clinical Context: Tobramycin may be an option for the empiric parenteral treatment of UTI. It is used in skin, bone, and skin-structure infections caused by Staphylococcus aureus, Pseudomonas aeruginosa, and E coli, as well as by Klebsiella, Proteus, and Enterobacter species.
This agent is indicated in the treatment of staphylococcal infections when penicillin or potentially less toxic drugs are contraindicated and when bacterial susceptibility and clinical judgment justify its use. Dosing regimens are numerous and are adjusted on the basis of creatinine clearance (CrCl) and changes in the volume of distribution.
Antibiotics are used to treat bacterial infections of the urinary tract. Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens in the context of the clinical setting.
Clinical Context: Acetaminophen is a nonopioid systemic analgesic used for moderate voiding discomfort caused by UTI.
Clinical Context: Ibuprofen is a nonsteroidal anti-inflammatory agent that is used to provide symptomatic relief of dysuria.
These agents are used to provide relief from voiding symptoms caused by UTIs.
Clinical Context: Phenazopyridine exerts local topical anesthetic or analgesic action on urinary mucosa. It is used for symptomatic relief of pain, burning, urgency, frequency, and other discomforts arising from irritation of the lower urinary tract mucosa caused by infection, trauma, surgery, endoscopic procedures, passage of sounds, or catheters. Its analgesic action may reduce or eliminate the need for systemic analgesics. When used concomitantly with antibiotics for UTI, phenazopyridine should not be used for longer than 2 days.
These agents are used to relieve burning, spasticity, and pain during voiding caused by UTIs.
Method Findings Bright-field or phase-contrast microscopy of centrifuged urinary sediment Bacteria Gram stain of uncentrifuged or centrifuged urinary sediment Bacteria Nitrite and leukocyte esterase test Positive = UTI likely Nitrite test Positive = UTI probable Leukocyte esterase test Positive = UTI probable *Negative microscopic findings for bacteria do not rule out a UTI, nor do negative results of dipstick testing for nitrite and leukocyte esterase. False-negative nitrite readings are especially common in children.
Method Finding Suprapubic aspiration If a UTI is present, bacteria are likely to be proliferating in bladder urine with growth of any organism except 2000-3000 CFU/mL coagulase-negative staphylococci. Catheterization in a girl or midstream, clean-void collection in a circumcised boy Febrile infants and children with UTI usually have >50,000 CFU/mL of a single urinary pathogen; however, UTI may be present with 10,000-50,000 CFU/mL of a single organism.* Midstream, clean-void collection in a girl or uncircumcised boy UTI is indicated when >100,000 CFU/mL of a single urinary pathogen is present in a symptomatic patient. Pyuria usually present. A UTI may be present with 10,000-50,000 CFU/mL of a single bacterium.* Any method in a girl or boy If the patient is asymptomatic, bacterial growth is usually >100,000 CFU/mL of the same organism on different days. If pyuria is absent, this result probably indicates colonization rather than infection. *Patients with urinary frequency (ie, decreased bladder incubation time) are those most likely to have bacteria proliferating in the urinary bladder in the presence of low colony counts.
Drug Dosage and Route Comment Ceftriaxone 50-75 mg/kg/day IV/IM as a single dose or divided q12h Do not use in infants < 6 wk of age; parenteral antibiotic with long half-life; may displace bilirubin from albumin Cefotaxime 150 mg/kg/day IV/IM divided q6-8h Safe to use in infants < 6 wk of age; used with ampicillin in infants aged 2-8 wk Ampicillin 100 mg/kg/day IV/IM divided q8h Used with gentamicin in neonates < 2 wk of age; for enterococci and patients allergic to cephalosporins Gentamicin Term neonates < 7 days: 3.5-5 mg/kg/dose IV q24h
Infants and children < 5 years: 2.5 mg/kg/dose IV q8h or single daily dosing with normal renal function of 5-7.5 mg/kg/dose IV q24h
Children ≥5 y: 2-2.5 mg/kg/dose IV q8h or single daily dosing with normal renal function of 5-7.5 mg/kg/dose IV q24hMonitor blood levels and kidney function if therapy extends >48 h Note: IM = intramuscular; IV = intravenous; q = every.
Protocol Daily Dosage Sulfamethoxazole and trimethoprim (SMZ-TMP) 30-60 mg/kg SMZ, 6-12 mg/kg TMP divided q12h Amoxicillin and clavulanic acid 20-40 mg/kg divided q8h Cephalexin 50-100 mg/kg divided q6h Cefixime 8 mg/kg q24h Cefpodoxime 10 mg/kg divided q12h Nitrofurantoin* 5-7 mg/kg divided q6h *Nitrofurantoin may be used to treat cystitis. It is not suitable for the treatment of pyelonephritis, because of its limited tissue penetration.
Agent Single Daily Dose Nitrofurantoin * 1-2 mg/kg PO Sulfamethoxazole and trimethoprim (SMZ-TMP) * 5-10 mg/kg SMZ, 1-2 mg/kg TMP PO Trimethoprim 1-2 mg/kg PO *Do not use nitrofurantoin or sulfa drugs in infants younger than 6 weeks. Reduced doses of an oral first-generation cephalosporin, such as cephalexin at 10 mg/kg, may be used until the child reaches age 6 weeks. Ampicillin or amoxicillin are not recommended because of the high incidence of resistant E coli.