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Pivmecillinam for Uncomplicated Lower Urinary Tract Infections Caused by Staphylococcus saprophyticus-Cumulative
Filip Jansåker1,2, Marianne Bollestad3,4, Ingvild Vik5
1Department of Clinical Microbiology, Hvidovre Hospital, University of Copenhagen, 2650 Hvidovre, Denmark. erik.filip.jansaaker@regionh.dk.
Abstract:
Objectives: To investigate pivmecillinam´s efficacy in uncomplicated lower urinary tract infection (UTI) caused by Staphylococcus saprophyticus-considered non-susceptible to mecillinam. Methods: Participants with confirmed UTIs caused by S. saprophyticus from four randomized controlled trials, where pivmecillinam was empirically given to females with symptoms of UTIs. The primary outcome was defined as a cumulative clinical effect-symptom resolution during the first eight days of therapy, without a recurrence of UTI symptoms in the long-term follow-up (approximately four weeks). Secondary outcomes included the bacteriological effect-elimination of the causative agent, with or without new uropathogenic bacteria present in the first control urine sample. Significant bacteriuria was defined as ≥103 bacteria/mL. The antibiotic susceptibility testing was done by disc diffusion methodology, according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Results: Seventy-four females (18-55 years) were empirically treated with pivmecillinam for UTIs caused by S. saphrophyticus (mean age 25 years; standard deviation (SD) 5.8). The cumulative clinical effect was 53/74 (72%), and the bacteriological effect was 51/59 (86%). Conclusion: Pivmecillinam showed a high clinical and bacteriological effect in UTIs caused by S. saprophyticus in these four clinical trials. The characterization of non-susceptibility for mecillinam regarding the treatment of UTIs caused by this common pathogen may need to be revised.
Insights
Pivmecillinam effectively treats uncomplicated urinary tract infections (UTIs) caused by Staphylococcus saprophyticus, even when the bacteria are considered non-susceptible. This study shows high clinical and bacteriological success rates, suggesting a need to re-evaluate mecillinam non-susceptibility criteria.
Area of Science:
- Infectious Diseases
- Pharmacology
- Urology
Background:
- Uncomplicated lower urinary tract infections (UTIs) are common, particularly in women.
- Staphylococcus saprophyticus is a frequent uropathogen, often exhibiting resistance to certain antibiotics.
- Pivmecillinam's efficacy against mecillinam-non-susceptible S. saprophyticus requires further investigation.
Purpose of the Study:
- To evaluate the clinical and bacteriological efficacy of pivmecillinam in treating UTIs caused by Staphylococcus saprophyticus.
- To assess pivmecillinam's effectiveness in cases where S. saprophyticus is considered non-susceptible to mecillinam.
Main Methods:
- Analysis of data from four randomized controlled trials involving women with S. saprophyticus UTIs empirically treated with pivmecillinam.
- Primary outcome: cumulative clinical effect (symptom resolution and no recurrence) within eight days and at four weeks.
- Secondary outcomes: bacteriological effect (pathogen elimination) and antibiotic susceptibility testing using EUCAST guidelines.
Main Results:
- Seventy-four women (mean age 25 years) with S. saprophyticus UTIs were treated.
- A cumulative clinical effect was observed in 72% (53/74) of participants.
- Bacteriological eradication was achieved in 86% (51/59) of cases.
Conclusions:
- Pivmecillinam demonstrates significant clinical and bacteriological efficacy against S. saprophyticus UTIs.
- Current criteria for mecillinam non-susceptibility in S. saprophyticus may need revision based on these findings.
- Pivmecillinam is a viable treatment option for UTIs caused by this pathogen.
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