Rosen & Barkin's 5-Minute Emergency Medicine Consult (591 page)

• Dysuria, urgency, frequency
  
• Back, flank, or abdominal pain
  
• Fever, chills
  
• Arthralgias, myalgias, malaise
  
• Nausea and/or vomiting
  
• Costovertebral angle/suprapubic tenderness
  
• Ill/toxic appearing
  
• Dehydration
  
• Occult pyelonephritis:
  
  • Invasion of upper urinary tract without clinical symptoms:
    
    • Suspect in lower UTI that does not resolve with standard treatment.
      

• Fever, irritability, lethargy, poor feeding, or jaundice may be only symptom in infants.
  
• Enuresis in previously toilet-trained child
  
• Common cause of a serious bacterial infection (SBI) in neonates, young children, and the immunocompromised (hematogenous spread)
  
• Renal scarring:
  
  • More common sequelae in young children than in adults
    
• Group B streptococci
  
• Etiologic agents in neonates
  

Commonly present atypically:

• Absence of classic dysuria/frequency
  
• Instead nausea/vomiting, diarrhea, fever, or altered mental status may predominate.
  

• Urinalysis (UA):
  
  • Clean-catch or catheterized urine specimen; catheterized specimen if:
    
    • Vaginal discharge or bleeding
      
    • Contaminated specimen
      
  • Pyuria: 5–10 WBCs, plus leukocyte esterase, plus nitrites:
    
    • If not present, consider alternate diagnosis.
      
    • Nitrite represents a gram-negative pathogens are present that is converting dietary nitrates to nitrites.
      
    • Note that some uropathogens such as
      Pseudomonas
      ,
      Enterococcus
      , and
      S. Saprophyticus
      are not nitrate reducers
      
  • Hematuria:
    
    • White cell cast: Renal origin of pyuria
      
• Urine culture and sensitivity:
  
  • Obtain in:
    
    • Suspected pyelonephritis
      
    • Unclear diagnosis
      
    • Treatment failures, recurrent infections
      
    • High clinical suspicion, with negative UA
      
  • >100,000 colony-forming units (CFU)/mL is positive.
    
  • 10
    ²
    –10
    ⁴
    CFU considered positive in:
    
    • Early infection
      
    • Clinical scenario consistent with UTI
      
    • Catheter or suprapubic specimen
      
    • Males
      

• CBC:
  
  • Leukocytosis
    
  • Does not rule in or out upper tract infection
    
• Blood cultures:
  
  • Not needed unless patient is septic; positive cultures do not correlate with more severe disease.
    
  • Bacteria identified more readily on urine culture
    
• Chemistries:
  
  • For patients with significant risk for electrolytes abnormalities (severe nausea/vomiting, or medication use)
    

• Imaging is required to differentiate pyelitis (no parenchymal involvement) and pyelonephritis (parenchymal involvement); however, this typically does not alter ED treatment.
  
• Bedside renal US:
  
  • Limited value for characterization except for detecting hydro/pyonephrosis/obstruction
    
• Helical CT:
  
  • Superior to renal US in detecting abnormalities/characterizing extent of disease
    
  • Consistent or concerning findings:
    
    • Stranding or inflammation and edema of parenchyma
      
    • Perinephric fluid
      
    • Calculi, obstruction
      
    • Renal/perinephric abscess
      
    • Intraparenchymal gas formation (emphysematous pyelonephritis)
      
• MRI:
  
  • Useful in:
    
    • Pregnant patients (lack of radiation)
      
    • Renal failure (lack of iodinated contrast)
      
  • Cost/availability limit usefulness in the ED
    
  • Obtain imaging if:
    
    • Concomitant stone/obstruction
      
    • At risk for emphysematous pyelonephritis/abscess (diabetes mellitus, immunocompromised, elderly)
      
    • Elective evaluation of genitourinary tract in males with pyelonephritis
      

• Obtain catheter urine specimen:
  
  • Vast majority of bag urine specimens will result in positive cultures (contaminants).
    
  • Helpful only for excluding disease if culture is negative
    
  • Catheterized or suprapubic specimen with >1,000 CFU is positive.
    
• Blood cultures usually performed for children <1 yr of age (due to risk for SBI)
  
• All children with 1st episode of pyelonephritis should have urinary tract imaging performed later to evaluate for UVR.
  
• Renal US:
  
  • Within 48 hr if no clinical improvement
    
  • Within 3–6 wk if clinical improvement
    

Suprapubic bladder aspiration:

• When urethral catheterization is not successful, or not possible (phimosis, urethral stricture, etc.)
  
• Contraindicated when there is a overlying infection, a known anatomic abnormality (tumor), recent complete voiding/micturition
  

• Abdominal aortic aneurysm or dissection
  
• Appendicitis
  
• Cholecystitis
  
• Cystitis
  
• Diverticulitis
  
• Cervicitis/pelvic inflammatory disease
  
• Endometritis/salpingitis
  
• Inferior pneumonia
  
• Prostatitis/epididymitis
  
• Nephrolithiasis
  
• Renal/perinephric abscess
  
• Urethritis
  

TREATMENT

IV access for the ill/toxic-appearing patient with appropriate fluid resuscitation

Treat shock with 0.9% normal saline 500 mL–1 L (peds: 20 mL/kg) IV fluid bolus

• While shock needs to be treated aggressively, be cognizant of fluid overload in patients with comorbidities (renal failure, congestive heart failure).
  

• Parental antibiotics for:
  
  • Inability to tolerate oral therapy
    
  • Extremes of age, immunosuppression, and pregnancy
    
  • Failure of oral/outpatient therapy
    
  • Urinary obstruction
    
  • Suspected antibiotic-resistant organisms
    
• Empiric IV antibiotics:
  
  • Fluoroquinolones (not approved in children)
    
  • Aminoglycoside (gentamicin) plus ampicillin
    
  • 3rd-generation cephalosporin (ceftriaxone)
    
  • In pregnancy:
    
    • 3rd-generation cephalosporin
      
    • Gentamicin/ampicillin
      
    • Cefazolin
      
    • Aztreonam
      
• Outpatient oral antibiotics:
  
  • For nontoxic and otherwise healthy patient:
    
    • Fluoroquinolone: 7–14 day course
      
  • May administer 1 dose of parenteral antibiotics prior to oral antibiotics:
    
    • Ensures prompt cessation of bacterial proliferation
      
    • No literature addressing efficacy
      
• Antiemetics and analgesics
  

• Oral antibiotics:
  
  • Ciprofloxacin: 500 mg PO BID
    
  • Ciprofloxacin ER: 1,000 mg PO daily.
    
  • Levofloxacin: 750 mg PO daily (5 days)
    
  • Ofloxacin: 200 mg PO BID
    
  • Amoxicillin/clavulanic acid: 875 mg/125 mg PO BID
    
• IV antibiotics:
  
  • Ceftriaxone: 1 g IV q24h
    
  • Ciprofloxacin: 400 mg IV q12h
    
  • Ampicillin/sulbactam: 3 g IV q6h
    
  • Cefazolin: 1–1.5 g IV q8h
    
  • Gentamicin: 3–5 mg/kg IV load
    
  • Levofloxacin: 500 mg IV daily
    
  • Piperacillin–tazobactam: 3.375 g IV q8h
    

• Oral antibiotic liquid preparations for children:
  
  • Amoxicillin: 30–50 mg/kg/24h PO TID
    
  • Amoxicillin/clavulanic acid: 45 mg/kg/24h PO TID
    
  • Cefixime: 8 mg/kg PO daily
    
  • Cefpodoxime: 10 mg/kg/24h PO BID
    
  • Cephalexin: 50–75 mg/kg/24h PO QID
    
  • Erythromycin/sulfisoxazole: 50 mg erythromycin/kg/24h PO QID
    
• Parenteral antibiotics for admitted children:
  
  • Age 0–3 mo:
    
    • Cefotaxime (50–180 mg/kg/d TID) + ampicillin (50–100 mg/kg/d QID)
      
    • Gentamicin (1–2.5 mg/kg/d TID) + ampicillin
      
  • Age >3 mo:
    
    • May substitute ceftriaxone (50–100 mg/kg/d BID to daily) for cefotaxime
      

FOLLOW-UP

• Sepsis, ill/toxic appearance
  
• Inability to tolerate oral therapy
  
• Intractable nausea/vomiting
  
• Social situation prevents compliance.
  
• Pregnancy
  
• Indwelling urinary catheter
  
• Urinary obstruction/anatomic abnormalities
  
• Proximal obstruction,
  
• Immunosuppression/diabetes mellitus
  
• Extremes of age (children <2–6 mo)
  
• Failure of outpatient therapy/recent antibiotics
  

• Clinical course improving in ED
  
• Ability to maintain oral hydration
  
• Pain controlled with oral analgesic
  
• Normal renal function
  
• Follow-up in 48–72 hr
  

• Uncomplicated cases in patients without comorbidities can safely follow up with their primary care physicians.
  
• If cultures were obtained, patient will need to follow up on results for possible therapy change once antibiotic sensitivities are known.
  
• Pediatric patients all need to follow up with their pediatrician for required imaging for anatomic abnormalities
  
• Pregnant patients need repeat UA to assess for resolution/recurrence and possible suppressive therapy.
  
• Patients with recurrent infections and those with identified unusual or resistant organisms require close follow-up with urologic and/or infectious disease consultation.
  

• Primarily a clinical diagnosis with minimal lab work required
  
• Treat young, old, immunosuppressed, and pregnant patients aggressively.
  
• Consider other diagnoses (e.g., gynecologic etiologies, abdominal aortic aneurysm)