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Acute Pyelonephritis Workup

  • Author: Tibor Fulop, MD, FASN, FACP; Chief Editor: Vecihi Batuman, MD, FACP, FASN  more...
 
Updated: Aug 11, 2015
 

Approach Considerations

In the outpatient setting, pyelonephritis is usually suggested by the history and physical examination and supported by urinalysis results, which should include microscopic analysis. Other laboratory studies are used to identify complicating conditions and to assist in determining whether the patient should be admitted.

Easily diagnosed cases typically occur in women, both pregnant and nonpregnant.[6] Men, patients at the extremes of age, patients harboring subclinical pyelonephritis, and patients who are hospitalized may present with an insidious onset.

Imaging studies may be required to make the diagnosis in infants and children in whom pyelonephritis presents insidiously. Imaging studies are rarely indicated for the diagnosis of acute pyelonephritis in an adult who presents with typical signs and symptoms, but they may be warranted if the presentation is atypical or confusing. Imaging is also warranted if the patient deteriorates or does not respond to therapy, in which case the important considerations are nephrolithiasis, obstructive uropathy, and perinephric abscess.

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Collection of Urine Specimens

Urine specimens obtained for urinalysis and culture should approximate the urine contained in the bladder as closely as possible. The 3 procedures for collecting such a urine specimen are clean catch, urethral catheterization, and suprapubic needle aspiration.

Clean catch

When properly collected, a clean-catch specimen adequately reflects the microbiology of the urine in the bladder. This technique can be performed by ambulatory females aged 6 years and older who do not have any limiting physical handicap.

Importantly, female patients should wash only the area where urine is passed, wash front to back, hold the cup by the outside, and keep the labia spread while collecting the urine. This is to ensure that the urine goes into the cup without touching the labia. The presence of a large number of epithelial cells on microscopic examination suggests that the specimen is not a true clean catch and is unreliable for culture because of contamination with vaginal contents.

Clean-catch technique can also be performed by ambulatory males aged 6 years and older who do not have any limiting physical handicap. Specimens are usually reliable. Importantly, the patient should clean the head of the penis, retract the foreskin (if uncircumcised), maintain a good stream, and hold the cup by the outside. In the presence of epispadias or hypospadias, care must be taken to maintain a good stream while collecting the specimen.

Urethral catheterization

Catheterization poses a small risk of introducing bacteria into the normally sterile bladder environment. Circumstances that justify this risk when a urine culture is necessary include the following:

  • Inability to void, or difficulty voiding urine even with hydration
  • Marked obesity or redundant labia in females
  • Ill patients who cannot reliably perform the procedure
  • Performance of a urologic procedure during which a specimen can be collected
  • Children 2-6 years of age (if a clinician-assisted clean-catch specimen cannot be collected)

For details on performing this procedure, see Urethral Catheterization in Women and Urethral Catheterization in Men.

Suprapubic needle aspiration

Suprapubic needle aspiration is rarely necessary. It is indicated under the following circumstances:

  • An alternative is lacking
  • The need exists to exclude contamination from other methods of collection
  • The need exists to verify the presence of an infecting organism that is otherwise considered a contaminant
  • The need exists to verify infection in an infant who has a positive culture result from a specimen obtained from a strap-on device

For details on performing this procedure, see Suprapubic Aspiration.

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Urinalysis

Pyuria is defined as more than 5-10 WBCs per high-power field (hpf) on a specimen spun at 2000 rpm for 5 minutes. Almost all patients with pyelonephritis have significant pyuria (>20 WBCs/hpf), although the numbers may be smaller, particularly in those with subacute pyelonephritis.

The dipstick leukocyte esterase test (LET) helps screen for pyuria. LET results have a sensitivity of 75-96% and a specificity of 94-98% for detecting more than 10 WBC/hpf.

The nitrite production test (NPT) for bacteriuria has 92-100% sensitivity and 35-85% specificity. It may be falsely negative in the presence of diuretic use, low dietary nitrate, or organisms that do not produce nitrate reductase (eg, Enterococcus, Pseudomonas, Staphylococcus). Combined, the LET-NPT has a sensitivity of 79.2% and a specificity of 81%, which is too low for it to be used as the only screening study for bacteriuria.

Gross hematuria occurs infrequently with pyelonephritis and is more common with cystitis (hemorrhagic cystitis). When gross hematuria is present, the differential should include calculi, cancer, glomerulonephritis, tuberculosis, trauma, and vasculitis.

Microscopic hematuria may be present in patients with uncomplicated acute pyelonephritis, but other causes should be considered, particularly calculi. This is especially true if the patient does not respond to therapy. White cell casts are suggestive of pyelonephritis; however, centrifuge speeds (>2000 rpm) used for urinalysis sediment preparation often fracture them and lead to their absence in the sediment.

Proteinuria is expected (up to 2 g/day). When it exceeds 3 g/day, glomerulonephritis should be considered.

The presence of a single bacterium in an unspun urine specimen by oil-immersion microscopic examination is equivalent to at least 105 colony-forming units (cfu)/mL. Bacteria are identified much more easily on a stained versus an unstained specimen.

Urinary neutrophil gelatinase-associated lipocalin

Urinary neutrophil gelatinase-associated lipocalin (NGAL) is a sensitive biomarker for the diagnosis of acute pyelonephritis in children. In a case-control study of 134 children with acute pyelonephritis or febrile states of other etiology, NGAL values were significantly higher in children with acute pyelonephritis. At a cut-off value of 29.4 ng/mL, urinary NGAL had 92.5% sensitivity and 90.7% specificity for diagnosing acute pyelonephritis. NGAL was also useful for differentiating acute pyelonephritis from cystitis and differentiating cystitis from febrile states with etiology other than UTI.[7]

Urinary concentrations of NGAL may also help identify children with acute pyelonephritis who are at increased risk of developing renal scarring. In a study of 54 children, urinary NGAL levels were significantly higher in patients with acute pyelonephritis with scarring than in those without scarring. At a cut-off value of 7.32 ng/ml, the sensitivity and specificity of this marker for diagnosing scar formation were 81.3% and 66%, respectively.[8]

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Urine and Blood Cultures

Urine culture is indicated in any patient with pyelonephritis, whether treated in an inpatient or an outpatient setting, because of the possibility of antibiotic resistance. Reliable results require proper specimen collection.

Blood cultures are indicated in any patient who is being admitted or who has already been admitted. Approximately 12-20% of patients have cultures that are positive for infection. Bacteremia has not been associated with a poor outcome unless sepsis or another significant comorbidity is present.

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Indications for Imaging Studies

Imaging may be required to make the diagnosis in infants and children in whom pyelonephritis presents insidiously. Imaging is warranted at the time of admission in patients with the following conditions:

  • AIDS
  • Poorly controlled diabetes
  • Organ transplant (particularly renal)
  • Other immunocompromised state
  • Sepsis syndrome
  • Septic shock

Imaging early in the presentation of acute pyelonephritis may be more useful than previously thought. In one study, 16% of patients admitted for acute pyelonephritis were found to have new and clinically significant abnormalities on renal imaging at the time of admission. Later in the hospital course, imaging studies are used for the prompt evaluation of a potentially organ- or life-threatening complication.

Indications for imaging studies are as follows:

  • Fever or positive blood culture results that persist for longer than 48 hours
  • Sudden worsening of the patient’s condition
  • Toxicity persisting for longer than 72 hours
  • Complicated UTI

After acute pyelonephritis has resolved, imaging studies may be used during a follow-up examination to identify urinary tract abnormalities that can predispose the patient to infection. In addition, studies may be used in conjunction with urologic procedures, including cystoscopy.

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Computed Tomography

Contrast-enhanced helical/spiral computed tomography (CECT) is the imaging study of choice, both in adults and in children with acute pyelonephritis. CECT is more sensitive than ultrasonography and intravenous pyelography (which has only 25% sensitivity), and it can more readily identify alterations in renal parenchymal perfusion, alterations in contrast excretion, perinephric fluid, and nonrenal disease.

Noncontrast helical/spiral CT findings may be normal in acute pyelonephritis with mild parenchymal involvement, but the findings are usually positive when the involvement is moderate or severe. It is the standard study for demonstrating gas-forming infections, hemorrhage, inflammatory masses, and obstruction.

If findings are suggestive of nephrolithiasis complicating the presentation, a noncontrast CT scan of the kidneys, ureters, and bladder (KUB) or a CT urogram should be obtained to exclude the possibility of obstruction or hydronephrosis.[9] CT has 97% accuracy in identifying renal stones. (See the images below.)

Nonobstructing distal left ureteral calculus 2 X 1 Nonobstructing distal left ureteral calculus 2 X 1 X 2 cm.
Bilateral hydronephrosis. Bilateral hydronephrosis.

Abscesses should appear on CT scans as low-density masses with contrast enhancement of the wall from inflamed/dilated blood vessels (see the image below). Acute focal bacterial nephritis has a lobar distribution of inflammation, wedge-shaped hypodense lesions (postcontrast), and masslike hypodense lesions in severe infections. Xanthogranulomatous pyelonephritis may appear as large renal calculi, nonfunctioning kidneys, contrast enhancement around low attenuation areas, thickening of the Gerota fascia, and spherical areas of low attenuation.

Multiple abscesses, upper pole of left kidney. Multiple abscesses, upper pole of left kidney.
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Ultrasonography

Ultrasonography (US) can sometimes detect acute pyelonephritis, but a negative study does not exclude the possibility. Power Doppler US is superior to color Doppler US in the detection of pyelonephritis but remains inferior to contrast-enhanced helical/spiral computed tomography (CECT).

Renal US is nevertheless a useful imaging modality in patients with complicated UTIs, and it may be performed at the bedside in a patient who is hemodynamically unstable. It is relatively inexpensive, it does not involve radiation, and iodinated contrast is not needed. It is an alternative to CT to identify hydronephrosis if there is concern regarding nephrolithiasis.[9] US is useful in screening for urinary obstruction in children admitted for febrile illnesses.

On ultrasonography, a renal abscess may appear as a fluid-filled mass with a thick wall. Acute focal bacterial nephritis appears as a poorly defined mass with low-amplitude echoes and disruption of the corticomedullary junction. In xanthogranulomatous pyelonephritis, imaging reveals stones in approximately 70% of patients.

Ultrasonographic findings may be falsely negative in 36% of cases of perinephric abscesses. A drawback to ultrasonography is the difficulty in differentiating renal abscess from tumor; it also is difficult to interpret in a patient who is obese. Renal angiography may help differentiate renal abscess from renal tumor because an abscess often has increased peripheral vascularization (the remainder of the mass is avascular).

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Scintigraphy

Scintigraphy with technetium-99m dimercaptosuccinic acid (99m Tc-DMSA) is almost as sensitive clinically as contrast-enhanced helical/spiral computed tomography (CECT) in detecting focal renal abnormalities during acute pyelonephritis in adults. DMSA is a radiotracer that localizes to the renal cortex. This modality is not used much in adults, however, because the findings are not specific; focal abnormalities may indicate abscess, cyst, infarct, pyelonephritis, or tumor. Additionally,99m Tc-DMSA scintigraphy is much less available in the acute setting than CECT.

In children, however,99m Tc-DMSA scintigraphy is the preferred study, because it involves less radiation exposure than CT scans. It is excellent for helping detect inflammation, scarring, and the distribution of renal function between kidneys.

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Magnetic Resonance Imaging

Experience with magnetic resonance imaging (MRI) in evaluating acute pyelonephritis is limited but growing. MRI can detect renal infection or masses and urinary obstruction, and it can evaluate the renal vasculature.

In perinephric abscess, MRI may help define extension better than CT scan. As there is no radiation exposure, MRI can be used in pregnancy.[10] The cost and availability of MRI remain concerns, however.[10]

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CT and MR Urography

CT urography and MR urography are evolving modalities that surpass intravenous urography, which was the prior mainstay of urinary tract imaging.[11] CT urography provides a detailed anatomic depiction of the urinary tract. MR urography has the advantage of not using ionizing radiation and has the potential to provide more functional information than CT. However, MR urography is less established than CT urography and is less reliable in providing diagnostic image quality.[11]

CT urography and MR urography are currently used in the evaluation of hematuria and will become more applicable to the study of other urologic problems.

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Diagnosis of Papillary Necrosis

Histology and/or imaging studies may help make the diagnosis of papillary necrosis. The sloughed papillae may be obtained by straining the urine and sending for histology. Retrograde pyelography is the radiologic procedure of choice, but ultrasonography or CT scan also reveals the diagnosis.

Findings of early renal papillary necrosis include a dilated calyceal fornix, retracted or irregular papillary tip, and extension of contrast into the parenchyma. A club-shaped cavity in the medulla or papilla may be formed in later disease. When a separated papilla is surrounded by contrast, a ring may be visualized, which is characteristic of papillary necrosis.

For more information on this topic, see the Medscape Reference article Papillary Necrosis.

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Histologic Findings

Features of acute pyelonephritis include suppurative necrosis or abscess formation within the renal substance. In contrast, features of chronic pyelonephritis (chronic interstitial nephritis) include papillary atrophy and blunting, interstitial fibrosis with inflammatory infiltrate (ie, lymphocytes, plasma cells, neutrophils [occasional]), tubules (ie, dilated with possible colloid casts, contracted with atrophy of epithelium), and concentric fibrosis around the parietal layer of the Bowman capsule.

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Contributor Information and Disclosures
Author

Tibor Fulop, MD, FASN, FACP Professor of Medicine, Department of Medicine, Division of Nephrology, University of Mississippi Medical Center

Tibor Fulop, MD, FASN, FACP is a member of the following medical societies: American College of Physicians, American Society of Diagnostic and Interventional Nephrology, American Society of Hypertension, American Society of Nephrology

Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: Fresenius Medical Care, Hungary.

Specialty Editor Board

Eleanor Lederer, MD, FASN Professor of Medicine, Chief, Nephrology Division, Director, Nephrology Training Program, Director, Metabolic Stone Clinic, Kidney Disease Program, University of Louisville School of Medicine; Consulting Staff, Louisville Veterans Affairs Hospital

Eleanor Lederer, MD, FASN is a member of the following medical societies: American Association for the Advancement of Science, International Society of Nephrology, American Society for Biochemistry and Molecular Biology, American Federation for Medical Research, American Society for Bone and Mineral Research, American Society of Nephrology, American Society of Transplantation, Kentucky Medical Association, National Kidney Foundation, Phi Beta Kappa

Disclosure: Received grant/research funds from Dept of Veterans Affairs for research; Received salary from American Society of Nephrology for asn council position; Received salary from University of Louisville for employment; Received salary from University of Louisville Physicians for employment; Received contract payment from American Physician Institute for Advanced Professional Studies, LLC for independent contractor; Received contract payment from Healthcare Quality Strategies, Inc for independent cont.

Chief Editor

Vecihi Batuman, MD, FACP, FASN Huberwald Professor of Medicine, Section of Nephrology-Hypertension, Tulane University School of Medicine; Chief, Renal Section, Southeast Louisiana Veterans Health Care System

Vecihi Batuman, MD, FACP, FASN is a member of the following medical societies: American College of Physicians, American Society of Hypertension, American Society of Nephrology, International Society of Nephrology

Disclosure: Nothing to disclose.

Acknowledgements

Amy J Behrman, MD Associate Professor, Department of Emergency Medicine, Director, Division of Occupational Medicine, University of Pennsylvania School of Medicine

Amy J Behrman, MD is a member of the following medical societies: American College of Occupational and Environmental Medicine

Disclosure: Nothing to disclose.

Christopher Edwards, MD Resident Physician, Department of Emergency Medicine, University of Pennsylvania School of Medicine

Christopher Edwards, MD is a member of the following medical societies: American College of Emergency Physicians and Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

Judith Green-McKenzie, MD, MPH Associate Professor, Director of Clinical Practice, Occupational Medicine Residency Director, University of Pennsylvania School of Medicine

Judith Green-McKenzie, MD, MPH is a member of the following medical societies: American College of Occupational and Environmental Medicine, American College of Physicians, American College of Preventive Medicine, National Medical Association, and Society of General Internal Medicine

Disclosure: Nothing to disclose.

Eleanor Lederer, MD Professor of Medicine, Chief, Nephrology Division, Director, Nephrology Training Program, Director, Metabolic Stone Clinic, Kidney Disease Program, University of Louisville School of Medicine; Consulting Staff, Louisville Veterans Affairs Hospital

Eleanor Lederer, MD is a member of the following medical societies: American Association for the Advancement of Science, American Federation for Medical Research, American Society for Biochemistry and Molecular Biology, American Society for Bone and Mineral Research, American Society of Nephrology, American Society of Transplantation, International Society of Nephrology, Kentucky Medical Association, National Kidney Foundation, and Phi Beta Kappa

Disclosure: Dept of Veterans Affairs Grant/research funds Research

Chike Magnus Nzerue, MD Associate Dean for Clinical Affairs, Vice-Chairman of Internal Medicine, Meharry Medical College

Chike Magnus Nzerue, MD is a member of the following medical societies: American Association for the Advancement of Science, American College of Physicians, American College of Physicians-American Society of Internal Medicine, American Society of Nephrology, and National Kidney Foundation

Disclosure: Nothing to disclose.

Suzanne Moore Shepherd, MD, MS, DTM&H, FACEP, FAAEM Associate Professor, Education Officer, Department of Emergency Medicine, Hospital of the University of Pennsylvania; Director of Education and Research, PENN Travel Medicine

Suzanne Moore Shepherd, MD, MS, DTM&H, FACEP, FAAEM is a member of the following medical societies: Alpha Omega Alpha, American Academy of Emergency Medicine, American Society of Tropical Medicine and Hygiene, International Society of Travel Medicine, Society for Academic Emergency Medicine, and Wilderness Medical Society

Disclosure: Nothing to disclose.

William H Shoff, MD, DTM&H Director, PENN Travel Medicine; Associate Professor, Department of Emergency Medicine, Hospital of the University of Pennsylvania, University of Pennsylvania School of Medicine

William H Shoff, MD, DTM&H is a member of the following medical societies: American College of Physicians, American Society of Tropical Medicine and Hygiene, International Society of Travel Medicine, Society for Academic Emergency Medicine, and Wilderness Medical Society

Disclosure: Glaxo Smith Kline None None; Glaxo Smith Kline Honoraria Speaking and teaching

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

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Nonobstructing distal left ureteral calculus 2 X 1 X 2 cm.
Multiple abscesses, upper pole of left kidney.
Bilateral hydronephrosis.
Table 1. Bacterial Etiology of Urinary Tract Infections
Bacteria % Uncomplicated % Complicated
Gram negative    
Escherichia coli 70-95 21-54
Proteus mirabilis 1-2 1-10
Klebsiella spp 1-2 2-17
Citrobacter spp < 1 5
Enterobacter spp < 1 2-10
Pseudomonas aeruginosa < 1 2-19
Other < 1 6-20
Gram positive    
Coagulase-negative staphylococci 5-10* 1-4
Enterococci 1-2 1-23
Group B streptococci < 1 1-4
Staphylococcus aureus < 1 1-23
Other < 1 2
Adapted from Hooton TM. The current management strategies for community-acquired urinary tract infection. Infect Dis Clin North Am. Jun 2003;17(2):303-32. [Medline].



* S saprophyticus



Table 2. Outpatient Treatment for Pyelonephritis
First-line therapy
  • ciprofloxacin (Cipro) 500 mg PO BID for 7d or
  • ciprofloxacin extended-release (Cipro XR) 1000 mg PO daily for 7d or
  • levofloxacin (Levaquin) 750 mg PO daily for 5d
  • If fluoroquinolone resistance is thought to be >10%, administer a single dose of ceftriaxone (Rocephin) 1g IV or  a consolidated 24-hour dose of an aminoglycoside (gentamicin 7 mg/kg IV or  tobramycin 7 mg/kg IV or amikacin 20 mg/kg IV)
Second-line therapy
  • trimethoprim/sulfamethoxazole* 160 mg/800 mg (Bactrim DS, Septra DS) 1 tablet PO BID for 14d
  • If trimethoprim/sulfamethoxazole is used when the susceptibility is not known, an initial single IV dose of the following may also be given: ceftriaxone (Rocephin) 1 g IV or  a consolidated 24-h dose of an aminoglycoside (gentamicin 7 mg/kg IV or  tobramycin 7 mg/kg IV or amikacin 20 mg/kg IV)
Alternative therapy
  • Oral beta-lactams are not as effective for treating pyelonephritis; however, if they are used, administer with a single dose of ceftriaxone (Rocephin) 1 g IV or  a consolidated 24-h dose of an aminoglycoside (gentamicin 7 mg/kg IV or  tobramycin 7 mg/kg IV or amikacin 20 mg/kg IV)
  • amoxicillin-clavulanate (Augmentin) 500 mg/125 mg PO BID for 14d or
  • amoxicillin-clavulanate (Augmentin) 250 mg/125 mg PO TID for 3-7d or
  • cefaclor 500 mg PO TID for 7d
*Should generally be avoided in elderly patients because of the risk of affecting renal function.
Table 3. Inpatient Treatment for Acute Pyelonephritis
First-line therapy
  • ciprofloxacin (Cipro) 400 mg IV q12h for 10-14d or
  • levofloxacin (Levaquin) 250 mg IV q24h for 10d or
  • levofloxacin (Levaquin) 750 mg IV q24h for 5d
Second-line therapy
Extended-spectrum cephalosporins or penicillins:



  • ampicillin 500 mg IM/IV q6h or
  • ampicillin-sulbactam (Unasyn) 1.5 g IV q6h or
  • piperacillin-tazobactam (Zosyn) 3.375 g IV q6h or
  • ticarcillin-clavulanate (Timentin) 3.1 g IV 4-6h or
  • cefotaxime (Claforan) 1-2 g IV q8h or
  • ceftriaxone (Rocephin) 1 g IV q24h or
  • ceftazidime (Fortaz, Tazicef) 2 g IV q8h
  • All of the above can be administered with or without an aminoglycoside (except in pregnant patients); see Aminoglycosides, below
Carbapenems:



  • meropenem (Merrem) 500 mg IV q8h or
  • ertapenem (Invanz) 1 g IV q24h or
  • doripenem (Doribax) 500 mg IV q8h
Monobactam (penicillin allergy):



  • aztreonam (Azactam) 1 g IV q8-12h
Alternative therapy
Aminoglycosides (because of their potential nephrotoxicity, aminoglycoside antibiotics should be reserved for patients with serious and potentially life-threatening infections, and their dosage and blood levels should be carefully monitored to minimize the risk of nephrotoxicity):
  • gentamicin 3 mg/kg/day IV/IM in 3 divided doses or 7 mg/kg/day pulsed dosing or
  • tobramycin 3 mg/kg/day IV/IM in 3 divided doses or 7 mg/kg/day pulsed dosing or
  • amikacin 10 mg/kg/day IV/IM in 3 divided doses or 20 mg/kg/day pulsed dosing
Table 4. Treatment of Pyelonephritis During Pregnancy
Mild to moderate pyelonephritis
  • ceftriaxone (Rocephin) 1 g IV q24h or
  • cefepime (Maxipime) 1 g IV q12h or
  • cefotaxime (Claforan) 1-2 g IV q8h or
  • ceftazidime (Fortaz, Tazicef) 2 g IV q8h or
  • ampicillin 1-2 g IV q6h plus  gentamicin IV 1.5 mg/kg q8h
Severe pyelonephritis
If patient is immunocompromised and/or has incomplete urinary drainage:
  • ticarcillin-clavulanate (Timentin) 3.1 g IV q6h or
  • ampicillin-sulbactam (Unasyn) 1.5 g IV q6h or
  • piperacillin-tazobactam (Zosyn) 3.375 g IV q6h
Table 5. Pediatric Urinary Tract Infections
  Neonates Infants 6 weeks to 3 years of age Children 3-6 years of age Children 6-11 years of age
UTI frequency (%) 1 1.5-3 1.5-3 1.2
Female-to-male ratio 1:1.5 10:1 10:1 30:1
Route of infection Blood Ascending Ascending Ascending
Signs and symptoms Failure to thrive, fever, hypothermia, irritability, jaundice, poor feeding, sepsis, vomiting Diarrhea, failure to thrive, fever, irritability, poor feeding, strong-smelling urine, vomiting Abdominal pain, dysuria, enuresis, fever, gross hematuria, meningismus, strong-smelling urine, urinary urgency, urinary frequency, vomiting Dysuria, enuresis, fever, flank pain or tenderness, urinary urgency, urinary frequency
Predominant organism Klebsiella species E coli E coli, Proteus species in older boys E coli
Management Admit for intravenous ampicillin and gentamicin and further evaluation Admit for intravenous ampicillin and gentamicin and further evaluation Follow adult guidelines, but avoid fluoroquinolones, which are theoretically contraindicated due to potential effects on the musculoskeletal system Follow adult guidelines, but avoid fluoroquinolones, which are theoretically contraindicated due to potential effects on the musculoskeletal system
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