Undoubtedly, the most important part of the diagnostic workup for BPH is the history of symptoms you describe to your doctor. Your doctor may even ask you to keep a diary of your urinary habits, so he can assess how frequently and with what severity certain symptoms occur. The history includes other medical problems, especially neurological conditions like Parkinson's disease and stroke, which can cause urinary obstruction all by themselves. The existence of other medical conditions is also important in determining your fitness for surgery. A complete physical examination is essential to reaching a diagnosis.
Special attention is paid to the digital rectal exam and to the neurological exam.
Laboratory tests include a urinalysis to rule out blood or infection in the urine and a blood creatinine level to assess kidney function. On the basis of a history, physical exam, lab tests, and AUA symptom index, your urologist can usually diagnose BPH with a high degree of confidence. Other more sophisticated tests are available when the diagnosis is uncertain. Uroflowmetry is an inexpensive, painless test that can provide useful information. It involves drinking lots of fluids until you're ready to urinate, then voiding into the machine, which measures the flow rate of your stream.