Do you treat a urine culture positive for Lactobacillus (lactic acid bacteria)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: June 11, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Lactobacillus in urine culture typically does not require treatment. Lactobacilli are normal flora in the genitourinary tract, especially in women, and their presence in urine usually represents contamination during collection rather than true infection 1. Treatment is generally only considered if the patient has significant urinary symptoms, risk factors like immunosuppression, or very high colony counts with no other explanation for symptoms.

Key Considerations

  • The presence of Lactobacillus in urine culture often indicates contamination rather than infection 1.
  • Asymptomatic bacteriuria, including that caused by Lactobacillus, does not typically require treatment unless specific risk factors are present, such as pregnancy or upcoming urologic procedures 1.
  • Unnecessary antibiotic treatment can disrupt the normal microbiome and lead to antibiotic resistance, highlighting the importance of judicious antibiotic use 1.

Clinical Approach

  • If treatment is deemed necessary based on clinical presentation, options such as ampicillin or amoxicillin may be considered, but this should be approached with caution and only after considering the potential risks and benefits 1.
  • It's crucial to differentiate between true infection and contamination or asymptomatic bacteriuria to avoid unnecessary treatment.
  • Lactobacilli play a beneficial role in maintaining vaginal health, producing lactic acid that helps prevent colonization by pathogenic organisms, which is why they're often considered protective rather than pathogenic in the urogenital tract 1.

Evidence Summary

The most recent and highest quality evidence supports a conservative approach to treating Lactobacillus found in urine cultures, emphasizing the importance of considering the clinical context and potential consequences of unnecessary antibiotic treatment 1.

From the Research

Treatment of Urine Culture Positive for Lactobacillus

  • Lactobacillus is typically considered a contaminant when cultured from urine specimens, but there have been cases where it has been determined to be the causative microorganism of urinary tract infections (UTIs) 2.
  • In general, the treatment of UTIs depends on the causative microorganism and its susceptibility to antibiotics 3, 4, 5.
  • However, there is limited information available on the treatment of UTIs caused by Lactobacillus, as it is not typically considered a pathogen in this context.
  • One study found that Lactobacillus delbrueckii was the cause of a UTI in a female patient with chronic pyuria and urinary tract symptoms, but the treatment used in this case is not specified 2.
  • Another study discussed the treatment of UTIs caused by extended-spectrum Beta-lactamase-producing organisms, but did not mention Lactobacillus specifically 5.
  • A review of the literature on Lactobacillemia, a rare entity in immunocompromised patients, found that most patients with Lactobacillus bacteremia are immunosuppressed or have comorbidities, and that the diagnosis of these infections requires a mutual relationship between the physician and the microbiologist to rule out contamination risk 6.

Considerations for Treatment

  • The decision to treat a UTI caused by Lactobacillus should be based on the patient's symptoms and the results of the urine culture, as well as any underlying medical conditions that may affect the patient's immune system 4, 6.
  • It is essential to use antimicrobials wisely to avoid the development of resistance, especially in patients with compromised immune systems 3, 4, 5.
  • In some cases, Lactobacillus may be considered a contaminant, and treatment may not be necessary 2.
  • However, if treatment is deemed necessary, the choice of antibiotic should be based on the susceptibility of the Lactobacillus strain and the patient's medical history 3, 5.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.