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Editorial: Urinary tract infection vaccines – the ‘burning’ issue

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The current ‘hot topic’ in UTI is antibiotic‐free prevention. At the forefront of this is the development of new immunomodulating vaccines, which utilise the most common strains of uropathogens, both surface antigen or inactivated whole bacterium, to induce a host immune response to prevent recurrent infections. Vaccines currently with established randomised control trials (RCTs) are Uro‐Vaxom® (OM Pharma, Myerlin, Switzerland), Urovac® (Solco Basel Ltd, Basel, Switzerland) and ExPEC4V (GlycoVaxyn AG, Schlieren, Switzerland), which have recently been reviewed by Aziminia et al. [1].

Vaccines classically work by inducing a systemic adaptive host immune response by pre‐sensitisation to the bacterial surface antigen. As most uropathogens share similar antigenic structures, a broad spectrum response is possible against other pathogens and not limited solely to the bacteria within the vaccine itself.

UroVaxom® is an oral tablet composed of bacterial extracts from 18 strains of Escherichia coli given daily for 90 days. Its use has been reported in the literature since 1990 and was found in the systematic review to reduce UTI recurrence rates the most (risk ratio [RR] 0.67, 95% CI 0.57–0.78).

Urovac® is composed of 10 inactivated uropathogen strains including six E. coli strains and one Proteus mirabilis, Morganella morganii, Enterococcus faecalis and Klebsiella pneumoniae. It is delivered as a weekly vaginal suppository for three doses, followed by three booster doses at 6, 10 and 14 weeks. Urovac® has also been shown to effectively reduce UTI recurrence rates (RR 0.75, 95% CI 0.63–0.89).

ExPEC4V is composed of O‐antigens of four E. coli serotypes delivered as a single i.m. injection. Whilst effective in initial trials, to date there is only one RCT, which reported no reduction in UTI recurrence rates (RR 0.82, 95% CI 0.62–1.10).

Overall, Aziminia et al. [1] concluded that a firm conclusion about the efficacy of UTI vaccines could not be reached. The studies thus have in general been limited by many factors, including the definition of what constitutes a UTI, the heterogeneity of participants, and variable definitions of trial endpoints, making comparisons difficult [1]. More targeted research is therefore needed.

UTI is a major problem and is one of the most common infections worldwide, affecting disproportionately more women than men. In the UK, 40–50% of women experience at least one episode of UTI in their lifetime, of which 20–30% proceed to develop recurrent UTIs (as defined by three or more episodes of UTI within a 12‐month period) [2,3]. Yet despite its prevalence, mainstream preventative options rely heavily upon long‐term antibiotic usage, either as low‐dose prophylaxis or recurrent rescue courses.

However, the problem is the concurrent and rapid rise in global bacterial multidrug resistance, such that the WHO has declared antibiotic resistance as one of the biggest risks to public health in our lifetimes and created a Global Action Plan to combat this issue. There is, therefore, an urgent need to find antibiotic‐free alternatives.

More recently, site‐targeted immune response has been shown to be effective in delivering a UTI vaccine. In particular, the genitourinary tract harbours both an innate and adaptive mucosal immune system. Within this there is mucosa‐associated lymphoid tissue (MALT) through which immunocytes transit. This is part of a larger mammalian lymphoid organ system. Stimulation at one MALT site induces an activation and dissemination of immunity to other MALT sites. In particular the activation of the sublingual mucosa has been linked with a broad spectrum immune response in the genitourinary tract [4].

Uromune® (Q‐Pharma, Alicante, Spain) is a new sublingual vaccine targeting this pathway. Composed of inactivated E. coli, Klebsiella pneumoniae, Proteus vulgaris and Enterococcus faecalis, it has been shown in two large retrospective Spanish studies to decrease UTI recurrence by up to 90% when compared to antibiotic prophylaxis [5]. A prospective UK observational study found after 3 months of daily administration, 78% of women developed no further UTIs in the 12‐month follow‐up period [6]. To date, there is no RCT available on the efficacy of Uromune®, although one international multicentre phase III RCT is currently underway, due to report in 2019/2020.

In general, whilst initial trials on UTI vaccines show potential, further research is needed to bring UTI vaccinations into mainstream treatment. In particular, future trials need to have robust definitions of the following (which previous studies have often lacked):

  • Definition of UTI – presence of symptoms and bacteriuria, as opposed to asymptomatic bacteriuria, which is often self‐limiting; and
  • Defined eligibility criteria – previous studies included hugely variable populations that included patients with neurogenic bladders, males and females, patients with indwelling catheters, and even immunosuppressed patients.

Furthermore, whilst comparison against placebo is important, comparison against antibiotic prophylaxis, the current ‘gold standard’, is also vital in providing evidence of efficacy.

Finally, the longevity of the vaccines’s effects also needs to be determined, in particular whether and when a booster dose is required in order to maintain the immune memory.

Overall though the future is exciting on tackling this ‘burning issue’ of UTI prevention.

 

References

  1. Aziminia, N, Hadjipavlou, M, Philippou, Y, Pandian, SS, Malde, S, Hammadeh, MY. Vaccines for the prevention of recurrent urinary tract infections: a systematic review. BJU Int 2019; 123: 753– 68
  2. Foxman, B. Urinary tract infection syndromes: occurrence, recurrence, bacteriology, risk factors, and disease burden. Infect Dis Clin North Am 2014; 28: 1– 13
  3. Albert, X, Huertas, I, Pereiró, II, Sanfélix J, Gosalbes V, Perrota C. Antibiotics for preventing recurrent urinary tract infection in non‐pregnant women. Cochrane Database Syst Rev 2004; 3:CD001209
  4. Holmgren, J, Czerkinsky, C. Mucosal immunity and vaccines. Nat Med 2005; 11 ( Suppl.): S45– 53
  5. Yang, B, Foley, S, Toozs‐Hobson, P. Urinary tract infections: current and new preventative options. SM J Clin Med 2016; 2: 1018
  6. Yang, B, Foley, S. First experience in the UK of treating women with recurrent urinary tract infections with the bacterial vaccine Uromune®. BJU Int 2018; 121: 289– 92

 

Video: Vaccines for the prevention of recurrent urinary tract infections: a systematic review

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Vaccines for the prevention of recurrent urinary tract infections: a systematic review

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Abstract

Objectives

To systematically review the evidence regarding the efficacy of vaccines or immunostimulants in reducing the recurrence rate of urinary tract infections (UTIs).

Materials and Methods

The Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica dataBASE (EMBASE), PubMed, Cochrane Library, World Health Organization (WHO) International Clinical Trials Registry Platform Search Portal, and conference abstracts were searched up to January 2018 for English‐titled citations. Randomised placebo‐controlled trials evaluating UTI recurrence rates in adult patients with recurrent UTIs treated with a vaccine were selected by two independent reviewers according to the Population, Interventions, Comparators, and Outcomes (PICO) criteria. Differences in recurrence rates in study populations for individual trials were calculated and pooled, and risk ratios (RRs) using random effects models were calculated. Risk of bias was assessed using the Cochrane Collaboration’s tool and heterogeneity was assessed using chi‐squared and I2 testing. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to evaluate the quality of evidence (QOE) and summarise findings.

Results

In all, 599 records were identified, of which 10 studies were included. A total of 1537 patients were recruited and analysed, on whom data were presented. Three candidate vaccines were studied: Uro‐Vaxom® (OM Pharma, Myerlin, Switzerland), Urovac® (Solco Basel Ltd, Basel, Switzerland), and ExPEC4V (GlycoVaxyn AG, Schlieren, Switzerland). At trial endpoint, the use of vaccines appeared to reduce UTI recurrence compared to placebo (RR 0.74, 95% confidence interval [CI] 0.67–0.81; low QOE). Uro‐Vaxom showed the greatest reduction in UTI recurrence rate; the maximal effect was seen at 3 months compared with 6 months after initial treatment (RR 0.67, 95% CI 0.57–0.78; and RR 0.78, 95% CI 0.69–0.88, respectively; low QOE). Urovac may also reduce risk of UTI recurrence (RR 0.75, 95% CI 0.63–0.89; low QOE). ExPEC4V does not appear to reduce UTI recurrence compared to placebo at study endpoint (RR 0.82, 95% CI 0.62–1.10; low QOE). Substantial heterogeneity was observed across the included studies (chi‐squared = 54.58; P < 0.001, I2 = 84%).

Conclusions

While there is evidence for the efficacy of vaccines in patients with recurrent UTIs, significant heterogeneity amongst these studies renders interpretation and recommendation for routine clinical use difficult at present. Further randomised trials using consistent definitions and endpoints are needed to study the long‐term efficacy and safety of vaccines for infection prevention in patients with recurrent UTIs.

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Article of the month: Evaluation of axitinib to downstage cT2a renal tumours and allow partial nephrectomy: a phase II study

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Every month, the Editor-in-Chief selects an Article of the Month from the current issue of BJUI. The abstract is reproduced below and you can click on the button to read the full article, which is freely available to all readers for at least 30 days from the time of this post.

In addition to the article itself, there is an editorial written by a prominent member of the urological community and the authors have also kindly produced a video describing their work. These are intended to provoke comment and discussion and we invite you to use the comment tools at the bottom of each post to join the conversation. 

If you only have time to read one article this week, it should be this one.

Evaluation of axitinib to downstage cT2a renal tumours and allow partial nephrectomy: a phase II study

Cedric Lebacle* , Karim Bensalah†, Jean-Christophe Bernhard‡§, Laurence Albiges, Brigitte Laguerre**, Marine Gross-Goupil††, Herve Baumert‡‡, Herve Lang§§, Thibault Tricard§§, Brigitte Duclos¶¶, Armelle Arnoux***, Celine Piedvache***, Jean-Jacques Patard††† and Bernard Escudier

 

*Department of Urology, Bicêtre University Hospital, Assistance Publique-Hôpitaux de Paris, APHP, University Paris-Saclay, Le Kremlin-Bicêtre, †Department of Urology, Pontchaillou University Hospital, Rennes, ‡Department of Urology, Bordeaux University Hospital, Pellegrin Hospital, §French Research Network on Kidney Cancer UroCCR, Bordeaux, Department of Medicine, Gustave Roussy, University Paris-Saclay, Villejuif, **Department of Oncology, Eugene Marquis Centre, Rennes, ††Department of Medical Oncology, Bordeaux University Hospital, Saint-André Hospital, Bordeaux, ‡‡Department of Urology, Saint-Joseph Hospital, Paris, §§Department of Urology, Nouvel Hôpital Civil, ¶¶Department of Oncology, Hautepierre Hospital, Strasbourg University Hospital, Strasbourg, ***Paris-Sud Clinical Research Unit, Department of Statistics, Bicêtre University Hospital, Assistance Publique-Hôpitaux de Paris, Le Kremlin-Bicêtre and †††Department of Urology, Mont de Marsan Hospital, Mont de Marsan, France

 

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Abstract

Objective

To evaluate the ability of neoadjuvant axitinib to reduce the size of T2 renal cell carcinoma (RCC) for shifting from a radical nephrectomy (RN) to a partial nephrectomy (PN) indication, offering preservation of renal function.

Patients and Methods

Patients with cT2aN0NxM0 clear‐cell RCC, considered not suitable for PN, were enrolled in a prospective, multicentre, phase II trial (AXIPAN). Axitinib 5 mg, and up to 7–10 mg, was administered twice daily, for 2–6 months before surgery, depending on the radiological response. The primary outcome was the number of patients receiving PN for a tumour <7 cm in size after neoadjuvant axitinib.

Results

Eighteen patients were enrolled. The median (range) tumour size and RENAL nephrometry score were 76.5  (70–98) mm and 11 (7–11), respectively. After axitinib neoadjuvant treatment, 16 tumours decreased in diameter, with a median size reduction of 17% (64.0 vs 76.5 mm; P < 0.001). The primary outcome was considered achieved in 12 patients who underwent PN for tumours <7 cm. Sixteen patients underwent PN. Axitinib was tolerated in the present study, as has been previously shown in the metastatic setting. Five patients had grade 3 adverse events. Five patients experienced Clavien III–V post‐surgery complications. At 2‐year follow‐up, six patients had metastatic progression, and two had a recurrence.

Conclusion

Neoadjuvant axitinib in cT2 ccRCC is feasible and, even with a modest decrease in size, allowed a tumour shrinkage <7 cm in 12 cases; however, PN procedures remained complex, requiring surgical expertise with possible morbidity.

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Editorial: Expanding the feasibility of nephron‐sparing surgery: time for a paradigm shift?

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With the rapid implementation of ‘targeted’ therapies, kidney cancer has entered a new era where old paradigms are being challenged, and new ones can be explored. The idea of delivering ‘neoadjuvant’ systemic therapy to alter the surgical treatment of advanced RCC was suggested in this same journal ~10 years ago as a proof‐of‐concept study [1]. Since then, a plethora of small case series has investigated the safety and feasibility of different targeted agents in the preoperative setting to facilitate surgical resection of locally advanced disease, mostly with a ‘cytoreductive’ (rather than ‘curative’) intent.

In this issue of the BJU Int, Lebacle et al. [2] evaluated the role of neoadjuvant axitinib, an oral tyrosine kinase inhibitor currently recommended as a second‐line option for metastatic clear cell RCC, to downstage cT2 kidney cancer and allow a partial nephrectomy (PN). In this multicentre prospective study, 18 patients with RCC (median tumour size 7.6 cm and R.E.N.A.L. [Radius; Exophytic/Endophytic; Nearness; Anterior/Posterior; Location] score 11) were enrolled. A median tumour size reduction of 17% was obtained, and the primary outcome (‘clinical downstaging’ to cT1 to allow PN) was achieved in 12 patients (67%). Overall, 16 patients underwent PN, as this was successfully done also in four of six (67%) patients who were not ‘down‐staged’ by the drug. Notably, about half of the PNs were performed with a robotic approach. Whilst axitinib was well tolerated, five patients experienced a high‐grade complication after surgery, including one death. Interestingly, final pathology showed upstaging to pT3a disease in seven patients, and two positive margins. Moreover, about a third of patients had metastatic progression and two had recurrence at 2 years. Thus, while the authors noted axitinib to be effective in reducing tumour size and achieving a clinical downstaging in most patients, the significant presence of pT3a disease calls into question the overall efficacy (to truly pathologically downstage) or desirability (most of the tumours that were not downstaged still successfully underwent PN) of the study’s main stated aim.

The rapid adoption of robotic surgery and the increasing experience with PN techniques translated into expanding indications for minimally invasive nephron‐sparing surgery (NSS), to include also T1b and T2 renal masses [3], and the field is primed for a possible paradigm shift. Whether or not a PN is doable, regardless of the technique, remains in the hands of the surgeon, who makes that decision based on previous personal experience. This is also the case for the present study, where the primary outcome was simply represented by the number of patients who could get a PN (instead of a radical nephrectomy). As such, is such a subjective endpoint (feasibility of PN) clinically meaningful? While disagreement may occur over the risk of PN in complex and elective cases, the desirability of nephron preservation in imperative and most elective circumstances is supported by evidence that largely suggests that PN translates into better renal function. In addition, recent findings suggest that estimated GFR preservation might translate into better cancer‐specific survival [4]. Certainly, this type of endpoint (whether a PN is feasible) is prone to intrinsic bias and limitations.

Only a limited number of studies have specifically explored the role of neoadjuvant therapy to enable NSS with variable results [5] (Table 1) [2, 6, 7, 8, 9]. Overall, these studies suggest that even a modest tumour size reduction can facilitate kidney preservation in a significant number of cases. Amongst these studies, only one had assessed axitinib in this specific setting [9]. Differences in outcomes between that trial and the present one by Lebacle et al. [2] could be explained by differences in study populations and/or drug regimens. A more recent study by Karam et al. [10], showed that inter‐observer agreement regarding the feasibility of a PN is quite variable, which is not surprising. For this reason, those authors advocated the need for a ‘resectability score’.

In conclusion, utility of neoadjuvant therapy to modify tumour size and facilitate NSS is an active and exciting area of clinical investigation, fuelled by the rapidly changing landscape of systemic therapies for RCC. It is too early to call for a paradigm shift, but a few ongoing studies might provide some meaningful answers soon. Amongst these, the PADRES (Prior Axitinib as a Determinant of Outcome of REnal Surgery) is an ongoing North American multicentre phase II study of axitinib with the aim of recruiting 50 patients [5]. While waiting for more robust evidence, the use of neoadjuvant therapy to facilitate NSS should still be deemed as investigational.

References

  1. Shuch, B, Riggs, SB, LaRochelle, JC et al. Neoadjuvant targeted therapy and advanced kidney cancer: observations and implications for a new treatment paradigm. BJU Int 2008; 102: 692– 6
  2. Lebacle, C, Bensalah, K, Bernhard, JC et al. Evaluation of axitinib to downstage cT2a renal tumours and allow partial nephrectomy: a phase II study. BJU Int 2019; 123: 804– 10
  3. Bertolo, R, Autorino, R, Simone, G et al. Outcomes of robot‐assisted partial nephrectomy for clinical T2 renal tumors: a multicenter analysis (ROSULA Collaborative Group). Eur Urol 2018; 74:226– 32
  4. Antonelli, A, Minervini, A, Sandri, M et al. Below safety limits, every unit of glomerular filtration rate counts: assessing the relationship between renal function and cancer‐specific mortality in renal cell carcinoma. Eur Urol 2018; 74: 661– 7
  5. Bindayi, A, Hamilton, ZA, McDonald, ML et al. Neoadjuvant therapy for localized and locally advanced renal cell carcinoma. Urol Oncol 2018; 36: 31– 7
  6. Silberstein, JL, Millard, F, Mehrazin, R et al. Feasibility and efficacy of neoadjuvant sunitinib before nephron‐sparing surgery. BJU Int 2010; 106: 1270– 6
  7. Rini, BI, Plimack, ER, Takagi, T et al. A phase II study of pazopanib in patients with localized renal cell carcinoma to optimize preservation of renal parenchyma. J Urol 2015; 194: 297– 303
  8. Lane, BR, Derweesh, IH, Kim, HL et al. Presurgical sunitinib reduces tumor size and may facilitate partial nephrectomy in patients with renal cell carcinoma. Urol Oncol 2015; 33: 112.e15–21.
  9. Karam, JA, Devine, CE, Urbauer, DL et al. Phase 2 trial of neoadjuvant axitinib in patients with locally advanced nonmetastatic clear cell renal cell carcinoma. Eur Urol 2014; 66: 874– 80
  10. Karam, JA, Devine, CE, Fellman, BM et al. Variability of inter‐observer agreement on feasibility of partial nephrectomy before and after neoadjuvant axitinib for locally advanced renal cell carcinoma (RCC): independent analysis from a phase II trial. BJU Int 2016; 117: 629– 35

 

Video: Evaluation of axitinib to downstage cT2a renal tumours and allow partial nephrectomy: a phase II study

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Evaluation of axitinib to downstage cT2a renal tumours and allow partial nephrectomy: a phase II study

Read the full article

Abstract

Objective

To evaluate the ability of neoadjuvant axitinib to reduce the size of T2 renal cell carcinoma (RCC) for shifting from a radical nephrectomy (RN) to a partial nephrectomy (PN) indication, offering preservation of renal function.

Patients and Methods

Patients with cT2aN0NxM0 clear‐cell RCC, considered not suitable for PN, were enrolled in a prospective, multicentre, phase II trial (AXIPAN). Axitinib 5 mg, and up to 7–10 mg, was administered twice daily, for 2–6 months before surgery, depending on the radiological response. The primary outcome was the number of patients receiving PN for a tumour <7 cm in size after neoadjuvant axitinib.

Results

Eighteen patients were enrolled. The median (range) tumour size and RENAL nephrometry score were 76.5  (70–98) mm and 11 (7–11), respectively. After axitinib neoadjuvant treatment, 16 tumours decreased in diameter, with a median size reduction of 17% (64.0 vs 76.5 mm; P < 0.001). The primary outcome was considered achieved in 12 patients who underwent PN for tumours <7 cm. Sixteen patients underwent PN. Axitinib was tolerated in the present study, as has been previously shown in the metastatic setting. Five patients had grade 3 adverse events. Five patients experienced Clavien III–V post‐surgery complications. At 2‐year follow‐up, six patients had metastatic progression, and two had a recurrence.

Conclusion

Neoadjuvant axitinib in cT2 ccRCC is feasible and, even with a modest decrease in size, allowed a tumour shrinkage <7 cm in 12 cases; however, PN procedures remained complex, requiring surgical expertise with possible morbidity.

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Article of the week: Relationship between oxidative stress and lower urinary tract symptoms: results from a community health survey in Japan

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Every week, the Editor-in-Chief selects an Article of the Week from the current issue of BJUI. The abstract is reproduced below and you can click on the button to read the full article, which is freely available to all readers for at least 30 days from the time of this post.

In addition to the article itself, there is an editorial written by a prominent member of the urological community and the authors have also kindly produced a video describing their work. These are intended to provoke comment and discussion and we invite you to use the comment tools at the bottom of each post to join the conversation. 

If you only have time to read one article this week, it should be this one.

The relationship between oxidative stress and lower urinary tract symptoms: Results from the community health survey in Japan

Teppei Matsumoto*, Shingo Hatakeyama* , Atsushi Imai*, Toshikazu Tanaka*, Kazuhisa Hagiwara*, Sakae Konishi*, Kazutaka Okita*, Hayato Yamamoto*, Yuki Tobisawa*, Tohru Yoneyama†, Takahiro Yoneyama*, Yasuhiro Hashimoto†, Takuya Koie‡, Shigeyuki Nakaji§ and Chikara Ohyama*†

 

*Department of Urology, †Department of Advanced Transplant and Regenerative Medicine, Hirosaki University
Graduate School of Medicine, Hirosaki, ‡Department of Urology, Gifu University Graduate School of Medicine, Gifu
and §Department of Social Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
Read the full article

Abstract

Objective

To investigate the relationship between oxidative stress and lower urinary tract symptoms (LUTS) in a community‐dwelling population.

Materials and Methods

The cross‐sectional study included 1 113 people who participated in the Iwaki Health Promotion Project of 2015 in Hirosaki, Japan. LUTS were assessed using structured questionnaires, including the International Prostate Symptom Score (IPSS) and the Overactive Bladder Symptom Score (OABSS). IPSS > 7, OABSS > 5, nocturia score > 1, or urge incontinence score > 1 were defined as moderate to severe symptoms. 8‐Hydroxy‐2′‐deoxyguanosine (8‐OHdG) and advanced glycation end products (AGEs) were measured by urine analysis and skin autofluorescence, respectively. The relationship between oxidative stress and LUTS was investigated using logistic regression analyses (You can reduce aging under eye masks).

Fig. 1. Association between 8‐Hydroxy‐2′‐deoxyguanosine (8‐OHdG) and advanced glycation end product (AGE) levels. 8‐OHdG levels were significantly associated with AGE levels (R2 = 0.023, P < 0.001, Spearman’s rank correlation coefficient). However, the R2 value was too small to indicate strong correlation and the significant P value of this correlation does not reflect the strength of the relationship between the two biomarkers.

Results

This study included 431 men and 682 women. AGEs and 8‐OHdG levels were significantly higher in severe forms of LUTS. Multivariate logistic regression analyses showed that AGE levels were significantly associated with a higher frequency of nocturia but were not associated with IPSS, OABSS or urge incontinence. No significant association was observed between LUTS and 8‐OHdG levels.

Conclusions

We observed a significant association between AGE levels and nocturia score > 1. Further research is necessary to clarify a possible causal relationship between oxidative stress and nocturia.

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Editorial: Oxidative stress and lower urinary tract symptoms: cause or consequence?

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Oxidative stress has been defined as ‘an imbalance between oxidants and anti-oxidants in favour of the oxidants, leading to a disruption of redox signalling and control and/or molecular damage’ [1]. Reactive oxygen and nitrogen species (ROS/RNS) produced under oxidative stress are known to damage all cellular biomolecules (lipids, sugars, proteins and polynucleotides). ROS/RNS is often used as a generic term but it has been emphasized that all ROS/RNS molecules are not the same [2] and the term encompasses a diverse range of species, including, for example, superoxide, hydrogen peroxide, nitric oxide and peroxynitrite. The biological impacts of ROS/RNS depend critically on the particular molecule(s) involved, and on the microenvironment and physiological or pathological context in which it is being generated [2]. It should be emphasized that ROS are not only harmful agents that cause oxidative damage in pathologies but they also have important roles as regulatory agents in a range of biological phenomena. They are normally generated as by-products of oxygen metabolism; however, environmental stressors (ultraviolet radiation, ionizing radiations, pollutants, heavy metal and xenobiotics) contribute to greatly increase ROS/RNS production.

It is difficult to measure ROS/RNS, therefore, biomarkers are often used as a surrogate; however, many of the biomarkers are insufficiently validated and it is often difficult to draw general conclusions on their significance [3]. 8-OHdG, one of the major products of DNA oxidation, is one of the most commonly used biomarkers of oxidative stress. Advanced glycation end-products (AGEs) are a group of heterogeneous molecules that arise from the non-enzymatic reaction of reducing sugars with amino groups of lipids, DNA and especially long-lived proteins. This process occurs during normal metabolism but is even more pronounced under oxidative stress conditions. AGEs may be harmful and include modified proteins and/or lipids with damaging potential. Using 8-OHdG, AGEs and other biomarkers, several attempts have been made to link oxidative stress, either as a cause or contributor, or both, to a variety of diseases, including LUTS. As pointed out by Ghezzi et al. [4] ‘Today it is a challenge to find a disease for which a role of oxidative stress has not been postulated.’

Matsumoto et al. [5] investigated the possible relationship between some markers of oxidative stress and LUTS in a population of community-living subjects participating in a health promotion project. As markers of oxidative stress, they used 8-OHdG (urine) and AGEs (skin autofluorescence), while structured questionnaires were used to assess LUTS. In their study, despite univariate analyses revealing several significant associations, multivariate analyses showed that the only statistically significant finding was that AGEs were associated with moderate to severe nocturia. This association is thought-provoking but, without functional studies, difficult to evaluate. LUTS are multifactorial and reflect a number of different comorbidities/pathophysiologies. It cannot be excluded that this may contribute to the lack of associations between oxidative stress markers and symptoms.

The finding of an association (or lack of it) between biomarkers of oxidative stress and LUTS does not reveal whether oxidative stress causes or contributes to LUTS. If ROS/RNS were causative/contributing factors to LUTS, it would be predicted that a positive response to antioxidant therapy and a decrease in ROS/RNS levels would not only support an involvement but would also be a promising treatment approach. In a prospective cohort study in the USA of 1670 men aged 65–100 years, Holton et al. [6] examined whether dietary antioxidants were associated with a reduced likelihood of LUTS progression or an increased likelihood of LUTS. They found that there were no significant associations between multiple dietary antioxidants and LUTS progression or remission over 7 years. Many other attempts to validate and exploit chronic antioxidant therapies have provided disappointing results, and still there is no antioxidant with sufficient efficacy to be approved by health authorities [4]. The question of whether antioxidant therapy may be harmful has not yet been answered. If the cause of LUTS is an increase of ROS/RNS in the bladder, it is questionable whether normalization of indicators of oxidative stress is safe, considering that the normal function of ROS/RNS in the rest of the body may be affected.

The clinical relevance of oxidative stress as a pathophysiological factor in lower urinary tract dysfunction or as a treatment target for various lower urinary tract disorders is still unclear. In addition, it has not been established that antioxidant therapy has any beneficial effect on LUTS.

by Karl-Erik Andersson

References

  1. Sies H. Oxidative stress: a concept in redox biology and medicine. Redox Biol 2015; 4: 180–3
  2. Murphy MP, Holmgren A, Larsson NG et al. Unraveling the biological roles of reactive oxygen species. Cell Metab 2011; 13: 361–6
  3. Frijhoff J, Winyard PG, Zarkovic N et al. Clinical relevance of biomarkers of oxidative stress. Antioxid Redox Signal 2015; 23: 1144–70
  4. Ghezzi P, Jaquet V, Marcucci F, Schmidt HHHW. The oxidative stress theory of disease: levels of evidence and epistemological aspects. Br J Pharmacol 2017; 174: 1784–96
  5. Matsumoto T, Hatakeyama S, Imai A et al. Relationship between oxidative stress and lower urinary tract symptoms: results from a community health survey in Japan. BJU Int 2019; 123 877-84
  6. Holton KF, Marshall LM, Shannon J et al. Osteoporotic fractures in men study group. Dietary antioxidants and longitudinal changes in lower urinary tract symptoms in elderly men: the Osteoporotic Fractures in Men study. Eur Urol Focus 2016; 2: 310–8

 

Video: The relationship between oxidative stress and lower urinary tract symptoms: Results from the community health survey in Japan

/by

The relationship between oxidative stress and lower urinary tract symptoms: Results from the community health survey in Japan

 

Abstract

Objective

To investigate the relationship between oxidative stress and lower urinary tract symptoms (LUTS) in a community‐dwelling population.

Materials and Methods

The cross‐sectional study included 1 113 people who participated in the Iwaki Health Promotion Project of 2015 in Hirosaki, Japan. LUTS were assessed using structured questionnaires, including the International Prostate Symptom Score (IPSS) and the Overactive Bladder Symptom Score (OABSS). IPSS > 7, OABSS > 5, nocturia score > 1, or urge incontinence score > 1 were defined as moderate to severe symptoms. 8‐Hydroxy‐2′‐deoxyguanosine (8‐OHdG) and advanced glycation end products (AGEs) were measured by urine analysis and skin autofluorescence, respectively. The relationship between oxidative stress and LUTS was investigated using logistic regression analyses.

Results

This study included 431 men and 682 women. AGEs and 8‐OHdG levels were significantly higher in severe forms of LUTS. Multivariate logistic regression analyses showed that AGE levels were significantly associated with a higher frequency of nocturia but were not associated with IPSS, OABSS or urge incontinence. No significant association was observed between LUTS and 8‐OHdG levels.

Conclusions

We observed a significant association between AGE levels and nocturia score > 1. Further research is necessary to clarify a possible causal relationship between oxidative stress and nocturia.

View more videos

Article of the week: In utero myelomeningocele repair and urological outcomes: the first 100 cases of a prospective analysis

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Every week, the Editor-in-Chief selects an Article of the Week from the current issue of BJUI. The abstract is reproduced below and you can click on the button to read the full article, which is freely available to all readers for at least 30 days from the time of this post.

In addition to the article itself, there is an editorial written by a prominent member of the urological community and a podcast produced by our Resident podcasters, Giulia Lane and Kyle Johnson. The authors have also kindly produced a video describing their work.

These are intended to provoke comment and discussion and we invite you to use the comment tools at the bottom of each post to join the conversation. 

If you only have time to read one article this week, it should be this one.

In utero myelomeningocele repair and urological outcomes: the first 100 cases of a prospective analysis. Is there an improvement in bladder function?

Antonio Macedo Jr*†, Sergio Leite Ottoni*, Gilmar Garrone*, Riberto Liguori*, Sergio Cavalheiro‡§, Antonio Moron¶§ and Marcela Leal Da Cruz*

 

*Department of Urology, CACAU-NUPEP, †Department of Pediatrics, Federal University of São Paulo, ‡Department of Neurosurgery, Federal University of São Paulo, §Santa Joana Maternity Hospital, and Department of Obstetrics-Fetal Medicine, Federal University of São Paulo, São Paulo, Brazil

 

Read the full article

Abstract

Objectives

To evaluate the first 100 cases of in utero myelomeningocele (MMC) repair and urological outcomes in a prospective analysis aiming to define possible improvement in bladder function.

Patients and methods

We used a protocol consisting of a detailed medical history, urinary tract ultrasonography, voiding cystourethrography, and urodynamic evaluation. Patients were categorised into four groups: normal, high risk (overactive bladder with a detrusor leak‐point pressure >40 cm H2O and high filling pressures also >40 cm H2O), incontinent, and underactivity (underactive bladder with post‐void residual urine), and patients were treated accordingly.

Fig.2. Hydronephrosis in relation to the underlying bladder pattern.

Results

We evaluated 100 patients, at a mean age of 5.8 months (median 4 months), classified as high risk in 52.6%, incontinent in 27.4%, with underactive bladder in 4.2%, and only 14.7% had a normal bladder profile. Clean intermittent catheterisation was initiated in 57.3% of the patients and anticholinergics in 52.6%. Antibiotic prophylaxis was initiated in 19.1% of the patients presenting with vesico‐ureteric reflux.

Conclusion

The high incidence of abnormal bladder patterns suggests little benefit of in utero MMC surgery concerning the urinary tract.

 

Read more Articles of the week

Editorial: Bladder function and fetal treatment of myelomeningocele

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In utero myelomeningocele repair and urological outcome: the first 100 cases of a prospective analysis. Is there an improvement in bladder function? Comments on bladder function and fetal treatment of myelomeningocele [1].

Prenatal care with maternal screening for neural tube defects and high‐resolution maternal fetal sonography has led to the early diagnosis of fetal myelomeningocele [2]. Revolutionary fetal surgery to correct myelomeningocele in utero has reduced the need for cerebrospinal fluid shunting and improved motor outcomes in these babies, based on 30‐month follow‐up data [3]. Sponsored by the National Institute of Health, the prospective randomized ‘Management of Myelomeningocele Study’ (MOMS) trial documented the outcomes of 158 patients assessed after either fetal repair prior to 26 weeks’ gestation or standard postnatal repair of the myelomeningocele defect. The trial was stopped early when evaluation showed that the primary outcome, rate of shunt placement, in the postnatal repair group (82%) was approximately double that in the prenatal surgery group (40%). Prenatal surgery also resulted in improvement in outcomes for mental development, motor function and ambulation, also evaluated at 30 months postnatally. However, prenatal surgery was associated with an increased risk of preterm delivery and uterine dehiscence at the time of delivery.

Bladder function was also evaluated at 30 months in the MOMS trial, comparing the need for clean intermittent catheterization (CIC) in 115 patients with adequate urological follow‐up, consisting of clinical outcomes in respect to continence, sonographic appearance of the kidneys and bladder and urodynamic evaluation [4]. Prenatal surgery did not significantly reduce the need for CIC measured at 30 months of age, but was associated with less bladder trabeculation and open bladder neck. Longer follow‐up was recommended and is in progress to document further bladder outcomes.

Macedo et al. [1] report similar short‐term bladder outcomes in 100 patients undergoing in utero myelomeningocele repair. Their report documented bladder characteristics in these patients at a mean postnatal age of ~6 months. In their unique cohort, antenatal diagnosis of fetal myelomeningocele was made at ~21 weeks’ gestation, in utero surgery was performed at ~25.5 weeks’ gestation and preterm birth occurred at ~33 weeks’ gestation, parameters consistent with the patients in the MOMs trial. Short‐term evaluation showed that ~53% of the patients had high‐risk bladders with poor compliance, ~27% were incontinent with weak sphincteric activity and only ~15% had normal urodynamic profiles. CIC was initiated in ~ 57% of the Macedo et al. cohort, again similar to the MOMs trial. The long‐term outcomes after potty training and during childhood and adolescence will be especially interesting in this valuable cohort.

Some of the pitfalls that will need to be accounted for include the validation and standardization of urodynamic testing [5]. Even at the same institution with clinicians who have undergone similar training, consistent interpretation of urodynamic studies can be variable, potentially affecting therapeutic options [6].

The goal of patients, parents and providers is to avoid the urological sequelae of myelomeningocele. To date, the reality is that the majority of these children, whether or not they have undergone in utero fetal repair or postnatal surgery, will require the assistance of CIC for urological health to protect the kidneys from excess pressure, to facilitate bladder emptying and urinary continence and prevent UTI.

 

References

  1. Macedo, A, Ottoni, SL, Garrone, G et al. In utero myelomeningocele repair and urological outcome: the first 100 cases of a prospective analysis. Is there an improvement in bladder function? BJU Int 2019; 123: 676– 81
  2. Meller, C, Aiello, H, Otano, L. Sonographic detection of open spina bifida in the first trimester: review of the literature. Childs Nerv Syst 2017; 33: 1101– 6
  3. Adzick, NS, Thom, EA, Spong, CY et al. A randomized trial of prenatal versus postnatal repair of myelomeningocele. N Engl J Med 2011; 364: 993– 1004
  4. Brock, JW, Carr, MC, Adzick, NS et al. Bladder Function After Fetal Surgery for Myelomeningocele. Pediatrics 2015; 136: e906– 13
  5. Bauer, SB, Nijman, RJ, Drzewiecki, BA, Sillen, U, Hoebeke, P, International Children’s Continence Society Standardization Subcommittee. International Children’s Continence Society standardization report on urodynamic studies of the lower urinary tract in children. Neurourol Urodyn 2015; 34: 640– 7
  6. Dudley, AG, Casella, DP, Lauderdale, CJ et al. Interrater reliability in pediatric urodynamic tracings: a pilot study. J Urol 2017; 197: 865– 70

 

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