#08 Click here to see the previous editions March 23, 2024
About the editor
About Devicare

Welcome to UTI News! In this newsletter, we will cover the most important hot topics in the field of urinary tract infections every two months. Stay tuned for updates and insights on this important topic.

Subscribe now


facebook facebook facebook facebook

Hello urologists, gynaecologists, primary care doctors and all of you who have to deal with urinary tract infections. Urinary tract infection management and prevention are one of the activities on a routine basis for all caregivers. This Newsletter intends to review the latest recommendations for managing and preventing urinary infections. Our focus is to reduce the number of infections, avoid antibiotic use when not indicated to prevent resistance, and review the evidence about non-antibiotic measures to prevent infections. Scientific support of the evidence and practice guideline recommendations will be key to all the information in the Newsletter.

The focus of this issue is the revision of three articles. The main topic reviewed is recurrent urinary tract infections. The first one revises the evidence proposed by guidelines from different associations regarding the diagnosis and management of recurrent urinary tract infections. We also review the factors that may affect bacterial growth in urine for E. coli. The evidence showed that E. coli growth in urine decreases in case of low urine pH. Therefore, modification in urine pH may be useful for the prevention and management of urinary tract infections.

img Guideline of guidelines: management of recurrent urinary tract infections in women.
Kwok M, McGeorge S, Mayer-Coverdale J, Graves B, Paterson DL, Harris PNA, Esler R, Dowling C, Britton S, Roberts MJ. BJU Int. 2022 Nov;130 Suppl 3(Suppl 3):11-22
img 3'
https://bjui-journals.onlinelibrary.wiley.com/doi/10.1111/bju.15756 img

The article revises the recommendations for the diagnosis and management of recurrent urinary tract infections. Most of the guidelines recommend urine culture in the case of recurrent urinary tract infections. However, in the case of sporadic uncomplicated urinary tract infections, treatment with antibiotics may be prescribed and a urinary culture is not required. The diagnostic evaluation should rely on ultrasound and more extensive image studies are not required routinely. The main focus of the revision is management and preventive measures in women with recurrent urinary tract infections. Although antibiotic prophylaxis offers a moderate or stong recommendations, not antibiotics measures should be the prescribe as first intention.

Topical vaginal oestrogen replacement usually is recommended by European Association of Urology (EAU), American Association of Urology (AUA/CUA/SUFU), UK National Institute for Health and Care Excellence (NICE) and the Society of Obstetricians and Gynaecologists of Canada (SOGC). However, patients should be advised that the topical cream can lead to adverse effects such as vaginal itching, burning, or bleeding in 20% of women. Other measures such as Cranberry supplements, D-mannose, Methenamine and intravesiscal glycosaminoglycan (GAG) therapy, the recommendation is weak. Regarding the immunoprophylaxis only EAU offers a strong recommendation.

Methenamine hippurate was recommended by the SSGO as a short-term therapy based on a Cochrane meta-analysis of four studies, including 456 patients, reported a possible benefit (RR 0.24, 95% CI 0.07–0.89) with limited reports of adverse events. Moreover, the ALTAR trial (alternative to prophylactic antibiotics for the treatment of recurrent urinary tract infections in women) reported that methenamine hippurate was not inferior to daily low-dose antibiotics based on an absolute difference of 0.49 episodes/person year.

img Effects of pH, nitrite, and ascorbic acid on nonenzymatic nitric oxide generation and bacterial growth in urine.
Carlsson S, Wiklund NP, Engstrand L, Weitzberg E, Lundberg JO. Nitric Oxide. 2001 Dec;5(6):580-6.
img 2'
https://pubmed.ncbi.nlm.nih.gov/11730365/ img

The article explores the impact of acidic urine on bacterial growth, focusing on the evidence suggesting that bacteria can produce nitrite in urine during urinary tract infections (UTIs). When nitrite undergoes acidification, it generates nitric oxide (NO) and other reactive nitrogen oxides, which exhibit toxicity against various microorganisms. The study revealed a significant reduction in the growth of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus saprophyticus when nitrite was added to acidified urine. Notably, this inhibition was further intensified by the presence of ascorbic acid.

In summary, the findings demonstrate that the growth of three common urinary pathogens is substantially impeded in mildly acidic urine containing nitrite. The bacteriostatic effect observed with acidified nitrite is likely attributable to the release of NO and other toxic reactive nitrogen intermediates. These results offer insights into the well-recognized therapeutic benefits of urinary acidification, such as through the administration of L-methionine (Metiofitina®), in both treating and preventing urinary tract infections.

img Rapid Growth and Metabolism of Uropathogenic Escherichia coli in Relation to Urine Composition.
Reitzer L, Zimmern P. Clin Microbiol Rev. 2019 Oct 16;33(1):e00101-19.
img 3'
https://pubmed.ncbi.nlm.nih.gov/31619395/ img

The research investigated the metabolic processes of Uropathogenic Escherichia coli (UPEC), a predominant bacterial strain responsible for a significant portion of urinary tract infections (UTIs). The analysis delves into the correlation between urine composition and the growth and metabolic activities of UPEC. Typically, urine maintains an average pH of around 6.0, with variations ranging from 5 to 8.

Pooling data from two primary sources reveals the presence of ample amino acids and carbohydrates serving as energy substrates, along with abundant phosphorus, sulfur, and nitrogen sources. In a mouse model of UTI, mutants deficient in enzymes related to the tricarboxylic acid cycle, gluconeogenesis, and the nonoxidative branch of the pentose cycle exhibit reduced competitiveness compared to their parental strains, aligning with the notion of amino acids as primary energy sources. Although not all genes are essential, many are confirmed to be necessary through mouse models. Evolutionary studies in the laboratory suggest that swift nutrient uptake, without significant metabolic reprogramming, suffices to support rapid growth. Proteins and pathways facilitating rapid growth emerge as potential targets for alternative or supplementary therapies.

These findings may indicate that a combination of urea and low pH exerts bacteriostatic effects, possibly due to the intensified denaturing impact of urea under low pH conditions. Conversely, higher pH levels and reduced urea concentrations are conducive to bacterial growth, a conclusion supported by clinical evidence.

facebook twiter youtube instagram
Aviso Legal | Política de privacidada
Este mail ha sido enviado a {{ contact.email }} por Devicare Lit Control.
Si quiere darse de baja de las comunicaciones de la Stone News puede enviarnos un correo electrónico a
dop@devicare.com o pinchar aquí.
Av. Can Domènech s/n | Eureka Building UAB Research Park | 08193 Cerdanyola del Vallès,
Barcelona | España
Copyright (c) 2023 Devicare Lit-Control.