Management of Urine Culture with >100,000 Units of Lactobacillus

Clinical Significance of Lactobacillus in Urine

• Lactobacillus species are explicitly identified in clinical guidelines as organisms that are not considered clinically relevant urine isolates for otherwise healthy individuals 1, 2
• The American Academy of Pediatrics guidelines specifically state that "Organisms such as Lactobacillus spp, coagulase-negative staphylococci, and Corynebacterium spp are not considered clinically relevant urine isolates" 1

Diagnostic Considerations

• True urinary tract infections (UTIs) are diagnosed based on both quantitative urine culture results and evidence of pyuria and/or bacteriuria 1, 2
• The presence of Lactobacillus alone, even at high colony counts, does not constitute a UTI 1, 2
• Treating asymptomatic bacteriuria may be harmful and should be avoided 2

When to Consider Treatment

• If the patient has symptoms of UTI (dysuria, urgency, frequency) and evidence of pyuria 2

Conclusion for Clinical Practice

• Do not treat with antibiotics if the patient is asymptomatic 1, 2
• Consider the organism identity (Lactobacillus) as non-pathogenic in most contexts 1, 2
• Reserve antimicrobial therapy for cases with clear evidence of infection with recognized uropathogens 1, 2