Ultrasonic measurement of bladder weight as a possible predictor of acute urinary retention in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia

[Diagnostic work-up of benign prostatic hyperplasia : The German S2e-guideline 2023 part 1]

BACKGROUND

Lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH; in German guidelines: benign prostatic syndrome [BPS]) is the most frequent urological disease in men and can result in a considerable deterioration of quality-of-life. BPS can be associated with LUTS, benign prostatic enlargement (BPE), and bladder outlet obstruction (BOO) or benign prostatic obstruction (BPO), respectively. The expert group on BPS of the German Society of Urology has re-evaluated the tests for the assessment of BPH and provides evidence-based recommendations.

OBJECTIVES

Presentation and evidence-based rating of tests for the assessment of patients with BPS.

MATERIALS AND METHODS

Summary and overview of chapters 5, 6, and 8 of the latest long version of the German S2e guideline on BPS.

RESULTS

The diagnostic work-up should clarify (1) whether the complaints of the patient are caused by BPS, (2) how relevant the complaints are and whether treatment is necessary, (3) whether complications of the lower or upper urinary tract already exist, and (4) which treatment will be most suitable. Baseline assessment should be done in all BPS patients and include history, measurement of LUTS and quality-of-life, urinalysis, serum prostate-specific antigen, post-void residual, ultrasound of the lower urinary tract, including measurements of prostate volume, intravesical prostatic protrusion and detrusor wall thickness, and ultrasound of the upper urinary tract. Additional tests can follow when questions remain unanswered after baseline assessment. These optional tests include bladder diaries, uroflowmetry, serum creatinine, urethrocystoscopy, other noninvasive tests for the determination of BOO/BPO such as penile cuff test, condom catheter method and near-infrared spectroscopy, and other imagining tests such as X‑ray and MRI investigations.

CONCLUSIONS

The updated German S2e guideline summarizes evidence-based recommendations on the diagnostic work-up, including the assessment of the BPS components BPE, LUTS, and BOO/BPO.

[Correlation between detrusor thickness, intravesical prostatic protrusion and maximum urinary flow in the monitoring of benign prostatic hyperplasia]

INTRODUCTION

Detrusor thickness (DT) and intravesical prostatic protrusion (IPP) are closely related to bladder outlet obstruction. The aim of our study was to look for correlation between DT, IPP and maximum urinary flow (Qmax).

METHODS

It is a prospective, observational study including men over fifty managed for benign prostatic hyperplasia. Low urinary tract symptoms were assessed with the International Prostatic Symptom Score (IPSS). Pelvic ultrasound was performed for all patients measuring prostatic volume, bladder volume, post- void residual, DT and IPP. Uroflowmetry was performed for all patients, Qmax was noted. Qmax equal or less than 15ml/s was considered pathologic.

RESULTS

Sixty patients were included for our study. Strong negative correlation was noted between DT, IPP and Qmax (r=-0.59, r=-0.61 respectively). Patients with pathologic Qmax had higher DT and IPP than those with normal Qmax, the difference was significant (P<0.01). Threshold values predicting pathologic Qmax were 3mm for DT and 7mm for IPP. ROC analysis reveals for DT an AUC of 0.84 (95% CI 0.76-0.92) and for IPP an AUC of 0.88 (95% CI 0.80-0.97).

CONCLUSION

Detrusor thickness and intravesical prostatic protrusion have strong negative correlation with Qmax. These parameters could be an alternative to Qmax measurement if uroflowmetry is unavailable.

LEVEL OF EVIDENCE

Grade B.

Serum interleukin 6 and acute urinary retention in elderly men with benign prostatic hyperplasia in China: a cross-sectional study

Background

While acute urinary retention (AUR) is a severe complication of benign prostatic hyperplasia (BPH), it can also indicate the progression of this common disease in aging men. This study aimed at exploring the possible relationship between serum interleukin 6 (sIL-6) and AUR in BPH patients.

Methods

A cross-sectional study was conducted based on 256 elderly men with BPH in China. The association between the sIL-6 level and the occurrence of AUR was evaluated by univariate and multivariable logistic regressions. The receiver operating characteristic (ROC) curve was utilized to determine the discriminant validity of the sIL-6 level and the optimal cut-off value.

Results

The concentration of sIL-6 was significantly elevated in the AUR group (P<0.001). A positive correlation was observed between the sIL-6 level and AUR in BPH patients [odds ratio (OR) =1.365, 95% confidence interval (CI): 1.174-1.586, P<0.001]. Based on the ROC curve analysis for sIL-6, the optimal cut-off point of 4.475 pg/mL was set to identify the occurrence of AUR in these patients [area under the curve (AUC) =0.7596, 95% CI: 0.6976-0.8216, P<0.001]. A high sIL-6 level (≥4.475 pg/mL) had a significantly stronger correlation with AUR (OR =9.666, 95% CI: 4.347-21.491, P<0.001).

Conclusions

There was a positive correlation between the sIL-6 level and the occurrence of AUR in elderly Chinese patients with BPH. This study provides potential strategies for the screening of BPH individuals with a possible risk of AUR, which may contribute to the early implementation of effective interventions to improve the quality of life and prognosis. Long-term prospective studies are still required to further illustrate the causal relationship.

The possible association between serum interleukin 8 and acute urinary retention in Chinese patients with benign prostatic hyperplasia

Acute urinary retention (AUR) is one of the progressive manifestations of benign prostatic hyperplasia (BPH). This cross-sectional study was conducted to analyse the possible association between serum interleukin 8 (sIL-8) and AUR in BPH patients to provide evidence of sIL-8 as a potential biomarker for the prediction of AUR. The relationship between sIL-8 levels and AUR was evaluated by logistic regressions in 245 ageing Chinese men with BPH. The discriminant validity of sIL-8 and the optimal cut-off value were determined by a receiver operating characteristic curve. The levels of sIL-8 increased significantly in BPH patients with AUR (p < 0.001). The sIL-8 concentration was positively correlated with AUR in BPH patients (OR = 1.024, 95% CI: 1.009-1.040, p = 0.002). The correlation with AUR in the group with a high sIL-8 level (≥43.05 pg/ml) was significantly enhanced (OR = 8.853, 95% CI: 2.433-32.205, p = 0.001). The sIL-8 level correlated with AUR in Chinese BPH patients independently. As a possible predictor, sIL-8 may contribute to the screening of high-risk populations for AUR to create opportunities for the early effective interventions to improve prognosis and enhance the quality of life. Prospective studies are needed to support all these results.

Effects of Qianlie Tongqiao Capsule on Bladder Weight and Growth Factors in Bladder Tissue of Rats with Testosterone-Induced Benign Prostatic Hyperplasia

Qianlie Tongqiao Capsule (QTC) is clinically confirmed to be efficacious and safe in treating lower urinary tract syndromes and bladder dysfunction that are induced by benign prostatic hyperplasia (BPH). However, the functional mechanisms of QTC remain unclear. We aim to investigate the effects of QTC on both bladder weight and several growth factors in the bladder tissue of rats with testosterone-induced BPH. BPH in the rats was established through bilateral orchiectomy and subcutaneous administration of testosterone propionate (5 mg/kg) dissolved in corn oil. At the end of the study, all bladder tissues were collected and weighed, and a histological examination was conducted using H&E staining. Immunohistochemistry and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) were applied to detect the expression of nerve growth factor (NGF), basic fibroblast growth factor (bFGF), and transformation growth factor-β1 (TGF-β1) in the bladder tissue. The expression of Bcl-2 and Bax in the bladder tissue was tested by Western Blot and qRT-PCR. We found that QTC, especially when administered in high-dosages, had a significant inhibitory effect on bladder weight gain and overexpression of NGF, bFGF, and TGF-β1 in rats with BPH. In addition, QTC downregulated and upregulated protein and mRNA expression of Bcl-2 and Bax in the bladder after prostatic obstruction, respectively. Furthermore, QTC balanced the Bcl-2/Bax ratio. Overall, these results reveal possible functional mechanisms of QTC in treating BPH-caused bladder dysfunction, and further studies are needed.

Non-invasive evaluation of lower urinary tract symptoms (LUTS) in men

Lower urinary tract symptoms (LUTS) are common in males over the age of 40 years old and are likely to increase with an aging population. Currently urodynamic studies are the gold standard to determine the aetiology of voiding dysfunction and LUTS. However, due to its invasive nature, a great number of non-invasive ultrasound based investigations have been developed to assess patients with symptomatic LUTS. The clinical application of non-invasive tests could potentially stratify patients who would require more invasive investigations and allow more precise patient directed treatment. A PubMed literature review was performed and we will discuss the non-invasive investigations that have been developed thus far, focusing on bladder wall and detrusor wall thickness (BWT & DWT), ultrasound estimated bladder weight (UEBW) and intravesical prostatic protrusion (IPP).

Current consensus and controversy on the diagnosis of male lower urinary tract symptoms/benign prostatic hyperplasia

Traditionally, male lower urinary tract symptoms (LUTS) have been considered a synonym for benign prostate hyperplasia (BPH) because most male LUTS develops in aging men. Medical treatment should be the first-line treatment for BPH and surgical intervention should be performed when there are complications or LUTS refractory to medical treatment. Recent investigations have revealed that bladder dysfunction and bladder outlet dysfunction contribute equally to male LUTS. In the diagnosis of LUTS suggestive of BPH (LUTS/BPH), the following questions should be considered: Is there an obstruction? Are the LUTS caused by an enlarged prostate? What are the appropriate tools to diagnose an obstructive BPH? Should patients with LUTS be treated before bladder outlet obstruction is confirmed? This article discusses the current consensus and controversies in the diagnosis of LUTS/BPH.

Can Bladder and Prostate Sonomorphology Be Used for Detecting Bladder Outlet Obstruction in Patients With Symptomatic Benign Prostatic Hyperplasia?

OBJECTIVE

To investigate the accuracy of the bladder and prostate sonomorphologic parameters for the diagnosis of bladder outlet obstruction (BOO) in patients with lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

First-visit men, aged ≥ 50 years, with LUTS/BPH were prospectively enrolled. Added to the initial basic evaluation, all patients underwent pelvic ultrasonography and pressure flow study. The pressure flow study was used as a reference standard for BOO, and according to its results, patients were divided into BOO and non-BOO groups. The sonomorphologic findings were compared between both groups, and the diagnostic accuracy of the significant parameters was determined.

RESULTS

In total, 157 patients were included. Of these, 48 (30.57%) had BOO and 109 (69.43%) did not. Bladder wall thickness (BWT), ultrasound estimated bladder weight (UEBW), and intravesical prostatic protrusion (IPP) were the sonomorphologic parameters that differed significantly between both groups (P < .001). By receiver operating characteristic curve analysis, the optimal cutoff values distinguishing patients with BOO were BWT of 3.7 mm (area under the curve [AUC]: 0.940), UEBW of 31.5 g (AUC: 0.835), and IPP of 10.9 mm (AUC: 0.874). The sensitivity, specificity, and accuracy of BWT, UEBW, and IPP were 95.00%, 90.91%, and 93.55%; 75.44, 57.97%, and 65.62%; and 87.90%, 76.43%, and 82.17%, respectively.

CONCLUSION

BWT, UEBW, and IPP measurements can be used to detect BOO in LUTS/BPH patients. The simple estimation of these sonomorphologic parameters by suprapubic approach makes these measurements potentially suitable methods to judge BOO noninvasively during the routine clinical evaluation of BPH.

The value of respective urodynamic parameters for evaluating the occurrence of complications linked to benign prostatic enlargement

PURPOSE

To assess the correlation between urodynamic parameters and urinary tract complications linked to benign prostatic enlargement (BPE), as well to assess the possible value of these parameters for predicting complications.

METHODS

We retrospectively analyzed the relationship between the complications and correlative urodynamic data of 486 BPH patients. Multivariate stepwise logistic regression was used to identify major independent predictors and establish regression models. Receiver operating characteristic (ROC) curves were constructed to evaluate the models' predictive values.

RESULTS

All of the individual parameters examined significantly correlated with most of the complications linked to BPE, except bladder calculus. According to ROC analysis, all of the areas under ROC curves (AUC), comparison of the individual parameters and the combined effects from the logistical regression models reached statistical significance (p < 0.05), and combining the parameters revealed a higher AUC compared to the individual parameters; however, all of the AUCs were below 0.9.

CONCLUSIONS

Urodynamic parameters are significantly correlated with most of the complications linked to BPE, and these parameters have predictive value for the occurrence of these complications with limited values.

Assessment of BPH/BOO

The assessment of men with bladder outflow obstruction relies on an adequate history and examination. Uroflowmetry and post-void residue estimation are very revealing and may be sufficient in the majority of men. The prostate-specific antigen test may be used to select men who are at a high risk of progression. In specific situations, cystometry may be required. We discuss the use of cystometry and the newer less-invasive methods of assessment that have emerged over the last few years, including ultrasound estimation of intravesical prostatic protrusion, prostatic urethra angle, detrusor wall thickness, ultrasound-estimated bladder weight, near-infrared spectroscopy and the condom catheter and penile cuff tests. Although these techniques show promise, they still require further modifications, standardization and testing in larger populations. In addition, they should be used in men where only specific questions need to be answered.

The use of ultrasound-estimated bladder weight in diagnosing bladder outlet obstruction and detrusor overactivity in men with lower urinary tract symptoms

Objectives:

Measurement of bladder weight using ultrasound estimates of bladder wall thickness and bladder volume is an emerging clinical measurement technique that may have a role in the diagnosis of lower urinary tract dysfunction. We have reviewed available literature on this technique to assess current clinical status.

Methods:

A systematic literature search was carried out within PubMed and MedLine to identify relevant publications. These were then screened for relevance. Preliminary results from our clinical experiments using the technique are also included.

Results:

We identified 17 published papers concerning the technique which covered clinical studies relating ultrasound-estimated bladder wall thickness to urodynamic diagnosis in men, women, and children together with change in response to treatment of bladder outlet obstruction. The original manual technique has been challenged by a commercially available automated technique.

Conclusion:

Ultrasound-estimated bladder weight is a promising non-invasive technique for the categorization of storage and voiding disorders in both men and women. Further studies are needed to validate the technique and assess accuracy of diagnosis.

Ultrasound estimated bladder weight in men attending the uroflowmetry clinic

AIMS

To determine if measurements of ultrasound estimated bladder weight (UEBW) provide an additional diagnostic tool when assessing men with lower urinary tract symptoms (LUTS) in the uroflowmetry clinic.

METHODS

One hundred men with LUTS attending the uroflowmetry clinic underwent transabdominal ultrasound measurement of bladder weight, using the BVM 9500 bladder scanner (Verathon Medical, Bothell, WA). These data were explored for any correlation between measurements of maximum flow rate (Q(max)) with UEBW, age, height, weight, body mass index (BMI), ICIQ M-LUTS score, M-LUTS voiding score, M-LUTS incontinence score, IPSS, IPSS quality of life score, voided volume, and post-void residual urine. Based on previously reported probabilities of bladder outlet obstruction (BOO), patients were grouped for analysis (Group 1 = Q(max) <10, Group 2 = Q(max) 10-15, Group 3 = Q(max) >15). A one-way ANOVA was undertaken to assess any difference in mean UEBW between the three groups.

RESULTS

Statistically significant negative correlations between Q(max) and age (r = -0.308, P = 0.002), M-LUTS voiding score (r = -0.298, P = 0.003), IPSS (r = -0.295, P = 0.003), and post-void residual (r = -0.213, P = 0.033) were observed. A statistically significant positive correlation between Q(max) and voided volume (r = 0.503, P < 0.01) was observed. No association between Q(max) and UEBW was observed (r = 0.12, P = 0.243). Mean UEBW for the three groups was remarkably similar. One-way ANOVA identified there was no statistically significant effect of UEBW on Q(max) F(2, 97) = 0.175, P = 0.840.

CONCLUSION

Mean UEBW did not differ significantly between the three Q(max) groups. Further work is required to investigate the relationship of Q(max) and UEBW in men with urodynamic confirmation of either BOO or detrusor underactivity.

Three-dimensional ultrasound bladder characteristics and their association with prostate size and lower urinary tract dysfunction among men in the community

OBJECTIVES

To characterize ultrasound bladder measures, and to determine whether these measures were associated with measures of lower urinary tract dysfunction.

METHODS

Three-dimensional ultrasounds were used to assess bladder surface area (SA), bladder wall thickness (BWT), and estimated bladder weight (EBW) in a random sample of the Olmsted County, Minnesota, male population. Uroflowometry was used to determine maximum urinary flow rates, and ultrasound was used to assess postvoid residual volume. Prostate volume was assessed with transrectal ultrasound and prostate-specific antigen (PSA) levels were assessed from serum samples. Correlation and linear regression analyses assessed relationships between bladder measures and prostate volume, PSA, maximum flow rate, and postvoid residual.

RESULTS

Among 259 men, median bladder SA was 228 cm(2) (25th, 75th percentiles: 180, 279), median BWT was 2.3 mm (25th, 75th percentiles: 1.8, 2.7), and median EBW was 48.5 g (25th, 75th percentiles: 43.7, 53.0). Decreased bladder SA was correlated with increased PSA level, increased prostate volume, higher American Urological Association Symptom Index (AUASI) scores (r(s) = -0.13 to -0.21; P = .03-.001), and decreased maximum flow rate (r(s) = 0.21, P = .001). Increased BWT was correlated with increased PSA level (r(s) = 0.22, P = .0003), increased prostate volume (r(s) = 0.17, P = .01), and decreased maximum flow rate (r(s) = -0.14, P = .03). Increased EBW was correlated with increased maximum flow rate (r(s) = 0.14, P = .03) and decreased AUASI score (r(s) = -0.13, P = .04).

CONCLUSIONS

Decreased SA and EBW were moderately associated with decreased maximum flow rate and increased AUASI scores, suggesting that such measures may provide insight into detrusor dysfunction.

Recent Advances in the Diagnosis of Benign Prostatic Hyperplasia

Benign prostatic hyperplasia (BPH) is a chronic and complex disease involving anatomical enlargement of the gland, real urinary obstruction and non-specific lower urinary tract symptoms (LUTS). LUTS are age-related lower urinary tract symptoms that affect 30-60% of men over the age of 40 years. LUTS could be due to causes related to the prostate, bladder or the central nervous system. Because the term “LUTS” is broader, it has replaced the term “prostatism”; the term LUTS BPH is the preferred one in urological literature

Comparison of intravesical prostatic protrusion, prostate volume and serum prostatic-specific antigen in the evaluation of bladder outlet obstruction

AIM

The aims of this study were to define the relationship between intravesical prostatic protrusion (IPP), prostate-specific antigen (PSA) and prostate volume (PV) and to determine which one of them is the best predictor of bladder outlet obstruction (BOO) due to benign prostatic enlargement.

METHODS

A prospective study of 114 male patients older than 50 years examined between November 2001 and 2002 was performed. They were evaluated with digital rectal examination, International Prostate Symptoms Score, PSA, uroflowmetry, postvoid residual urine measurement, IPP and PV using transabdominal ultrasound scan. Statistical analysis included scatter plot with Spearman's correlation coefficients and nominal logistic regression

RESULTS

Prostate volume, IPP and PSA showed parallel correlation. Although all three indices had good correlation with BOO index, IPP was the best. The Spearman rho correlation coefficients were 0.314, 0.408 and 0.507 for PV, PSA and IPP, respectively. Using receiver-operator characteristic curves, the areas under the curve for PV, PSA and IPP were 0.637, 0.703 and 0.772, respectively. The positive predictive values of PV, PSA and IPP were 65%, 68% and 72%, respectively. Using a nominal regression model, IPP remained the most significant independent index to determine BOO.

CONCLUSIONS

All three non-invasive indices correlate with one another. The study showed that IPP is a better predictor for BOO than PSA or PV.

Acute urinary retention in men: the risks and outcomes with medical therapy

This paper is restricted to the discussion of the relatively modern disorder of sudden painful inability to urinate in older men. It was not a common medical problem until the 19th century when, in developed countries, male life expectancy increased to beyond 60 years; it remains an uncommon problem in those developing countries where male life expectancy remains low, particularly in some sub-Saharan African countries where male life expectancy is only 44.8 years.

A rational approach to benign prostatic hyperplasia evaluation: recent advances

PURPOSE OF REVIEW

In this article we aim to outline the recent advances in the evaluation of a patient with symptoms suggestive of benign prostatic hyperplasia. We define the role of the clinical evaluation and techniques that are evolving for the appropriate management of a patient with benign prostatic hyperplasia. Both non-invasive and invasive investigation techniques are reviewed.

RECENT FINDINGS

Initiating early and appropriate treatment is the primary aim of investigation for a patient with lower urinary tract symptoms. Both clinical history and examination and appropriate investigations are vital to establishing a diagnosis. Symptom scores, prostate specific antigen and prostate volume were found to closely relate in predicting the progression of benign prostatic hyperplasia and in recent years increased interest has centred on the progression of this disease principally related to the development of new pharmacotherapy. Despite these positive findings further research is needed to develop reliable tools to predict progression. Newer ultrasound techniques hold promise for the future. Conventional pressure flow studies have a defined role in excluding patients who are less likely to benefit from prostatic surgery by providing information on detrusor function; and non-invasive urodynamic techniques need further evaluation but appear to be promising.

SUMMARY

The minimal initial evaluation of a patient with benign prostatic hyperplasia should include a thorough history, digital rectal and neurological examinations, symptom scoring (including quality of life and sexual score) and measurement of serum prostate specific antigen. Other methods should be reserved for more complex situations. Attempts should be made at identifying those patients in whom the disease process is likely to progress.