68 CHAPTER 3 Bladder outlet obstruction
Benign prostatic obstruction (BPO): symptoms and signs
Clinical practice guidelines
Such guidelines were developed to standardize the approach to diagnosis (and treatment) of men presenting with symptoms suggestive of BPH (see Box 3.1).1 Every guideline agrees that a history should be taken, an examination performed, and the severity of urinary symptoms be formally assessed using the IPSS (the International Prostate Symptom Score). This includes a measure of the “problems” caused by the patient’s symptoms (i.e., the degree to which the symptoms are troubling).
Urinary symptoms—what do they mean?
During the 1990s, the classic “prostatic” symptoms of frequency, urgency, nocturia, hesitancy, poor flow, an intermittent flow, and terminal drib- bling—traditionally said to indicate the presence of BOO due to benign prostatic enlargement—were shown to bear little relationship to prostate size, flow rate, residual urine volume, or urodynamic evidence of BOO. Age-matched elderly men and women have similar symptom scores (IPSS), despite the fact that women have no prostate and rarely have BOO.
Prostatism vs. LUTS vs. LUTS/BPH
Prostatism has thus been replaced by the expression lower urinary tract symptoms (LUTS), which avoids any implication about the cause of these symptoms. More recently, the expression LUTS/BPH has been used to describe the symptoms of BPH.
It doesn’t really matter whether you use prostatism, LUTS, or LUTS/ BPH as long as you remember that urinary symptoms may have nonprostatic causes. Try to avoid treating the prostate when the problem may lie elsewhere.
Ask specifically about the presence of the following:
•Bed-wetting suggests the presence of high-pressure chronic retention (look for distension of the abdomen due to a grossly enlarged bladder which is tense on palpation and dull to percussion).
•Marked frequency and urgency, particularly when also combined with bladder pain: look for carcinoma in situ of the bladder (urine cytology, flexible cystoscopy, and bladder biopsy).
•Macroscopic hematuria is sometimes due to a large vascular prostate, but exclude other causes (bladder and kidney cancer and stones) by flexible cystoscopy and upper tract imaging.
•Back pain and neurological symptoms (sciatica, lower limb weakness or tingling). Rarely, LUTS can be due to neurological disease.
1 Irani J, Brown CT, van der Meulen J, Emberton M (2003). A review of guidelines on benign prostatic hyperplasia and lower urinary tract symptoms: are all guidelines the same? Br J Urol Int 92:937–942.
BPO: SYMPTOMS AND SIGNS 69
Box 3.1 Websites for BPH clinical practice guidelines
•AUA guidelines: http://www.auanet.org/content/guidelines-and- quality-care/clinical-guidelines.cfm
•EAU guidelines: http://www.uroweb.org/files/uploaded_files/bph.pdf
•WHO (International Consensus Committee) guidelines: http:// www.who.int/ina-ngo/ngo/ngo048.htm
•Australian guidelines: http://www.health.gov.au/nhmrc/publications/ pdf/cp42.pdf
•German guidelines: http://dgu.springer.de/leit/pdf/3_99.pdf
•Singapore guidelines: http://www.urology-singapore.org.html/ guidelines_bph.htm
•Malaysian guidelines: http://www.mohtrg.gov.my/guidelines/bph98.pdf
•UK guidelines: http://www.rcseng.ac.uk/publications/
70 CHAPTER 3 Bladder outlet obstruction
Diagnostic tests in men with LUTS thought to be due to BPH
Clinical practice guidelines
Guidelines were developed as an attempt to standardize the approach to diagnosis and treatment of men presenting with symptoms suggestive of BPH1 (see Box 3.1). All agree that a history should be taken and an examination performed, and all recommend assessment of symptom severity using the IPSS (International Prostate Symptom Score). This includes a measure of the problems caused by the patient’s symptoms.
There is considerable variation among guidelines in terms of recommended diagnostic tests. High-quality guidelines (e.g., based on results of randomized trials) recommend few diagnostic tests2—urine analysis, completion of a voiding diary (frequency–volume chart) to detect the presence of polyuria and nocturnal polyuria (which may be the cause of a patient’s increased frequency or nocturia), and measurement of serum creatinine. They regard flow rate measurement and assessment of residual urine volume as optional tests.
Digital rectal examination (DRE) and PSA
DRE and PSA testing are done to detect nodules that may indicate an underlying prostate cancer and to provide a rough indication of prostate size. Size alone is not an indication for treatment, but if surgical treatment is contemplated, marked prostatic enlargement can be confirmed by transrectal ultrasound (TRUS) scan (prostate volume in the order of 100 mL or more increases the likelihood of an open prostatectomy).
Discuss the pros and cons of PSA testing with the patient.
Serum creatinine
This is a baseline measure of renal function, used to detect renal failure secondary to high-pressure urinary retention.
Post-void residual urine volume (PVR)
PVR varies considerably (by as much as 600 mL between repeat measurements) on the same or on different days.3 It cannot predict symptomatic outcome from transurethral resection of the prostate (TURP). Along with serum creatinine, it indicates whether watchful waiting is safe.
It is safe not to operate when the PVR volume is <350 mL,4,5 since the majority of men show no worsening of creatinine, no increase in PVR, and no worsening of symptoms and do not require TURP or other bladder outlet procedure.
Flow rate measurement
This is variously regarded as optional, recommended, and obligatory prior to undertaking surgical treatment for BPH. Like PVR, measured flow rate varies substantially on a given day,6 cannot distinguish between BOO and a poorly contractile bladder, and is not good at predicting the likelihood of a good symptomatic outcome after TURP.
DIAGNOSTIC TESTS IN MEN WITH LUTS 71
Pressure-flow studies
Such studies are reasonably good at predicting symptomatic outcome after TURP. However, most patients without obstruction have a good outcome, and the time, cost, and invasiveness of pressure-flow studies are perceived by most urologists as not justifying their routine use.
Renal ultrasonography
This is used to detect hydronephrosis if serum creatinine is elevated. The percentage of patients having upper tract dilatation on ultrasound according to serum creatinine is as follows: creatinine <115 mmol/L (1.5 mg/dL), 0.8%; creatinine 115–130 mmol/L (1.5–1.7 mg/dL), 9%; and creatinine >130 mmol/L (1.7 mg/dL), 33%.7
Further reading
Roehrborn CG (2008). Currently available treatment guidelines for men with lower urinary tract symptoms. Br J Urol 102:18–23.
Wei JT, Calhoun E, Jacobsen SJ (2005). Urologic diseases in America project: benign prostatic hyperplasia. J Urol 173:1256–1261.
Emberton M, Andriole GL, de la Rosette J, Djavan B, Hoefner K, Nvarette R et al. (2003). Benign prostatic hyperplasia: a progressive disease of aging men. Urol 61:267–273.
1 Roehrborn CG, Bartsch G, Kirby R, et al. (2001) Guidelines for the diagnosis and treatment of benign prostatic hyperplasia: a comparative international overview. Urology 58:642–650.
2 Irani J, Brown CT, van der Meulen J, Emberton M (2003) A review of guidelines on benign prostatic hyperplasia and lower urinary tract symptoms: are all guidelines the same? Br J Urol Int 92:937–942.
3 Dunsmuir WD, Feneley M, Corry DA, et al. (1996) The day-to-day variation (test–retest reliability) of residual urine measurement. Br J Urol 77:192–193.
4 Bates TS, Sugiono M, James ED, et al. (2003) Is the conservative management of chronic retention in men ever justified? Br J Urol Int 92:581–583.
5 Wasson JH, Reda DJ, Bruskewitz RC, et al. (1995) A comparison of transurethral surgery with watchful waiting for moderate symptom of benign prostatic hyperplasia. The Veterans Administration Cooperative Study Group on Transurethral Resection of the Prostate. N Engll Med 332:75–79.
6 Reynard JM, Peters TJ, Lim C, Abrams P (1996) The value of multiple free-flow studies in men with lower urinary tract symptoms. Br J Urol 77:813–818.
7 Koch WF, Ezz el Din KE, De Wildt MJ, et al. (1996) The outcome of renal ultrasound in the assessment of 556 consecutive patients with benign prostatic hyperplasia. J Urol 155:186–189.