Am Fam Physician. 2006;73(9):1632-1634
Benign prostatic hyperplasia (BPH) is a disease commonly found in older men. Distinguishing between BPH and other medical conditions that present as lower urinary tract symptoms can be difficult. These symptoms include obstruction, hesitancy, weak stream, irritation, urgency, frequency, and nocturia. Other conditions with similar symptoms include urinary tract and prostatic infections, medication side effects, overactive bladder, and prostate cancer. Beckman and Mynderse provide a review for physicians to help diagnose BPH and prevent the complications of untreated BPH, which include urinary tract infections, acute urinary retention, and obstructive nephropathy.
The severity and prevalence of BPH increase with age. Lower urinary tract symptoms in men older than 50 years usually are caused by BPH. To diagnose BPH in these patients, a medical history and physical examination should be combined with studies that quantify the severity of symptoms, the extent of prostatic enlargement, and the impact of enlargement on urine flow. The American Urological Association (AUA) symptom score is a reliable and validated seven-question survey that determines if patients have BPH. This survey also can help determine the severity of the patient's symptoms. If a symmetrically firm and enlarged prostate is found during digital rectal examination, a BPH diagnosis can be made. The feel of the prostate in BPH diagnosis often is compared with the tip of the nose. If a firm, nodular, asymmetric prostate support is found, a prostate cancer diagnosis can be made.
Uroflow studies, which are a noninvasive way to determine the effect of prostatic enlargement on urine flow, measure residual urine volumes. Urinalysis and prostate-specific antigen (PSA) studies also are appropriate. A urinalysis can help rule out an acute infectious cause for lower urinary tract symptoms. According to AUA guidelines, a PSA level is not required to make the BPH diagnosis. This is because a simple elevation cannot differentiate between BPH and prostate cancer. When used as part of the BPH diagnostic evaluation, the PSA level is strongly correlated with prostatic volume.
Medical therapy has become the mainstay of treatment for BPH. Watchful waiting is appropriate for patients with mild to moderate symptoms. The drugs of choice for treating BPH are alpha1-adrenergic antagonists. Orthostatic hypotension occurs most commonly with terazosin (Hytrin) and doxazosin (Cardura). It is important to note that patients being treated for erectile dysfunction should not receive this class of drugs because interaction with erectile dysfunction medication can cause profound hypotension. Other treatments include the 5-alpha reductase inhibitors finasteride (Propecia) and dutasteride (Avodart). With this drug class, sexual dysfunction, although not common, is reported. Evidence supports a combination of drugs from both classes as the first-line treatment for patients with severe symptomatic BPH and elevated PSA levels. Studies also support the use of saw palmetto as a safe and effective alternative treatment for BPH. Invasive therapy is reserved for severe symptoms that do not respond to medical treatment.
The authors conclude that obtaining a medical history that includes the AUA symptom score; performing a careful physical with a digital rectal examination; and conducting urinalysis, PSA, and uroflow studies can confidently exclude other causes of lower urinary tract symptoms and accurately diagnose BPH.