Benign prostatic hyperplasia often initially manifests as hesitancy (difficulty starting urination) or a weak urinary stream. Patients usually associate this with a need to strain their abdominal muscles when attempting to urinate. It also may present as a need to urinate more frequently during the day or at night. Urgency symptoms may or may not be present at this time. Blood in the urine, known as hematuria, can occur in patients with BPH either as a presenting symptom or later in the course of the disease.

As the disease progresses the nocturia, hesitancy, straining, and weak stream often worsen. The result is an inability to completely empty the bladder and the development of what is commonly referred to as "residual urine." The presence of residual urine may lead to other problems such as urinary tract infection, bladder stones, or in the worst case scenario, kidney failure.

Changes in the bladder and its ability to function may occur over time, especially if the obstruction goes untreated. The bladder responds to prostatic obstruction by developing a thicker, stronger muscular wall. Often this "compensatory hypertrophy" of the bladder, which is associated with development of scar tissue (collagen deposition) in the bladder wall, may make the bladder sensitive or irritable. Patients with a hypersensitive bladder may suffer urgency, resulting in the constant urge to urinate. In more severe cases, a patient may develop urge incontinence, or the inability to get to the bathroom before losing control of their bladder.

Untreated BPH may worsen. Residual urine may increase in volume, putting patients at increased risk of having stones, infections, or kidney failure. In the final stages of the disease, the patient is unable to empty his bladder at all and urinary retention ensues. This necessitates immediate medical intervention with the placement of a catheter, or rubber tube, either through the penis or lower abdominal wall into the bladder to facilitate drainage. Once at this stage, if ignored, the bladder can enter a final phase where the bladder fails to contract. This situation requires long-term drainage of the bladder with a catheter. In some cases this is continued until the bladder recovers and the obstruction is treated. If the bladder fails to recover, permanent drainage of the bladder with a catheter may be required.

Observation

Observation is usually reserved for those patients with minimal symptoms. Although symptoms are not particularly bothersome, these patients should continue to see their physicians regularly (yearly) for examinations and routine laboratory tests. These tests are designed to avoid having urine back up toward the kidneys (hydronephrosis) or bladder decompensation ("silent prostatism"). Patients followed by observation may eventually require medication or surgical intervention if they develop complications such as bladder stones, urinary retention (inability to urinate), recurrent urinary tract infections, or signs of kidney damage.