Can a urinary tract infection (UTI) present with fever and chills?

Urinary Tract Infections and Fever with Chills

Yes, urinary tract infections (UTIs) commonly present with fever and chills, particularly when the infection involves the upper urinary tract (pyelonephritis) or progresses to urosepsis. 1

Clinical Presentation of UTIs with Fever

Upper vs. Lower UTI Presentations

• Uncomplicated cystitis (lower UTI):

  • Typically presents with dysuria, frequency, urgency, and suprapubic discomfort
  • Usually without fever or systemic symptoms
  • Normal white blood cell count

• Pyelonephritis (upper UTI):

  • Characterized by fever (>38°C), chills, flank pain, and costovertebral angle tenderness
  • May include nausea, vomiting, and fatigue
  • Often accompanied by lower urinary tract symptoms (present in ~80% of cases) 2
  • Leukocytosis is common

Severity Indicators

• Signs of potential urosepsis:
  • High fever with shaking chills
  • Hypotension
  • Altered mental status
  • These symptoms require urgent evaluation and treatment 1

Diagnostic Approach

Laboratory Evaluation

• Urinalysis:

  • Pyuria (≥10 WBCs/high-power field) is typically present in UTIs
  • Absence of pyuria has high negative predictive value for UTI 1
  • Leukocyte esterase and nitrite tests on dipstick can help screen for infection

• Urine Culture:

  • Should be obtained when fever and urinary symptoms are present
  • Positive culture defined as ≥50,000 CFU/mL of a single uropathogen 2
  • Essential for guiding targeted antibiotic therapy

• Blood Tests:

  • Complete blood count with differential is recommended within 12-24 hours of symptom onset when infection is suspected 1
  • Elevated WBC count, high percentage of neutrophils, or left shift suggests bacterial infection

• Blood Cultures:

  • Indicated when urosepsis is suspected (high fever, shaking chills, hypotension) 1
  • Should be paired with urine cultures

Imaging

• Upper urinary tract imaging (ultrasound) should be considered to rule out obstruction or stone disease in patients with:

  • History of urolithiasis
  • Renal function disturbances
  • High urine pH 1

• Additional imaging (CT scan or excretory urography) is indicated if:

  • Patient remains febrile after 72 hours of treatment
  • Clinical deterioration occurs 1

Clinical Pearls and Pitfalls

Important Considerations

• The presence of fever and chills strongly suggests upper urinary tract involvement (pyelonephritis) rather than simple cystitis 1

• Prompt differentiation between uncomplicated and potentially obstructive pyelonephritis is crucial, as the latter can rapidly progress to urosepsis 1

• In elderly patients, UTIs may present atypically with confusion, falls, or functional decline rather than classic urinary symptoms 1

Common Pitfalls

• Treating asymptomatic bacteriuria:

  • Bacteriuria is common in older adults (10-50%) and should not be treated without symptoms 1
  • Urinalysis and cultures should not be performed for asymptomatic residents in long-term care facilities

• Relying solely on urinalysis:

  • Diagnosis should be based primarily on clinical symptoms integrated with laboratory findings
  • Pyuria alone has low positive predictive value for UTI 1

• Missing urosepsis:

  • Failure to recognize progression from UTI to urosepsis can lead to increased morbidity and mortality
  • Bacteremic UTIs have mortality rates of 18-50% 1

Conclusion

Fever with chills is a hallmark presentation of pyelonephritis and potential urosepsis, indicating upper urinary tract involvement or systemic spread of infection. These symptoms warrant prompt evaluation, appropriate cultures, and timely antibiotic therapy to prevent complications and reduce morbidity and mortality.