How do you manage a urinalysis indicating a urinary tract infection with significant epithelial cells, leukocyturia, and bacteriuria?

Interpreting a Urinalysis with Numerous Epithelial Cells, WBCs, and Bacteria

A urinalysis showing too many epithelial cells, 7-10 WBCs, and 1+ bacteria most likely represents a contaminated specimen rather than a true urinary tract infection (UTI), and a repeat collection via catheterization or clean-catch technique should be obtained before initiating treatment. 1

Understanding the Significance of Urinalysis Findings

Epithelial Cells

• Too many epithelial cells indicate significant contamination from the genital area during collection
• This contamination makes the WBC and bacteria findings unreliable
• Squamous epithelial cells come from the distal urethra, vagina, or skin and suggest improper collection technique

White Blood Cells (7-10 WBCs)

• Pyuria (presence of WBCs in urine) suggests inflammation
• According to AAP guidelines, WBCs alone without proper bacterial growth do not confirm UTI 1
• Pyuria without bacteriuria can occur in other conditions (chemical irritation, Kawasaki disease, etc.)

Bacteria (1+)

• Low-level bacteriuria with numerous epithelial cells strongly suggests contamination
• Per AAP guidelines, true UTI requires both:
  • Pyuria (WBCs in urine)
  • ≥50,000 CFU/mL of a single uropathogen from a properly collected specimen 1

Management Algorithm

Step 1: Evaluate the Specimen Quality

• Assess for contamination markers:
  • Excessive epithelial cells = likely contamination
  • Mixed bacterial flora = likely contamination
  • Proper specimen should have minimal epithelial cells

Step 2: Obtain a Proper Specimen

• For adults: Request a proper clean-catch midstream specimen
  • Provide clear collection instructions
  • Consider catheterization if clean catch not possible
• For children: Follow AAP guidelines for collection method 1
  • Catheterization or suprapubic aspiration for definitive diagnosis
  • Never treat based on bag specimen culture results

Step 3: Interpret the Repeat Urinalysis

• If repeat specimen shows minimal epithelial cells with persistent pyuria and bacteriuria:

  • Obtain urine culture before starting antibiotics
  • True UTI requires ≥50,000 CFU/mL of a single uropathogen 1
  • Treat according to local antibiogram and sensitivity patterns

• If repeat specimen shows minimal epithelial cells with no pyuria or bacteriuria:

  • No UTI is present
  • Consider other causes of symptoms

Treatment Considerations (If True UTI Confirmed)

First-line Antibiotics

• For uncomplicated UTI in adults:
  • Trimethoprim-sulfamethoxazole: 160/800 mg twice daily for 3 days 2
  • Amoxicillin-clavulanate: 875/125 mg twice daily for 7 days 3
  • Base choice on local resistance patterns

Duration of Therapy

• Uncomplicated cystitis in women: 3-day course
• Complicated UTI or pyelonephritis: 7-14 days 1

Common Pitfalls to Avoid

1. Treating contaminated specimens: Never treat based on a specimen with numerous epithelial cells
2. Misdiagnosing asymptomatic bacteriuria: Bacteriuria without pyuria may represent colonization, not infection
3. Failing to obtain culture: Always culture properly collected specimens before starting antibiotics
4. Inadequate follow-up: Persistent symptoms despite treatment warrant further investigation for structural abnormalities or resistant organisms 4

Special Considerations

• Pregnant women: Lower threshold for treatment and require follow-up cultures
• Immunocompromised patients: May present with atypical findings
• Catheterized patients: Different criteria apply for diagnosis of catheter-associated UTI
• Recurrent UTIs: May require imaging to identify structural abnormalities 1

Remember that proper specimen collection is the cornerstone of accurate UTI diagnosis. A contaminated specimen with numerous epithelial cells should never be used as the basis for treatment decisions.