Several problems of the urinary tract can be painful.
Infections of the urinary tract may occur anywhere along the line from the kidneys (within the upper abdomen) to the ureters (connecting the kidneys to the urinary bladder) to the bladder (midline in the pelvis) to the urethra (connecting the bladder to the outside of the body). Normally these organs and tissues contain sterile (aseptic) urine but any one of them may become infected with a pathogen (bacterium, virus or fungus) that causes disease. In general, an infection of the urinary tract causes symptoms acutely and these are treated promptly. When an infection is not treated it may become a chronic infection, cause inflammation, and result in a constant pelvic pain. A urinalysis and urine culture should be able to accurately identify the pathogen and allow proper treatment.
Kidney stones are solid crystals that form from the dissolved minerals within the urine. Kidney stones generally do not produce symptoms or pain until they obstruct the passage of urine. Symptoms of urinary obstruction include acute intense pain often within the flank or the pelvis, nausea, or bloody urine. This type of pain is called colic, which occurs when smooth muscle peristalsis (involuntary successive wavelike muscular contractions that moves food or urine through the intestines or urinary tract) results in sharp intermittent pain. Local urethral dilatation, ischemia and inflammation cause the pain associated with kidney stones, and if these conditions are prolonged then chronic pelvic pain may result. Diagnostic studies for kidney stones include the intravenous pyelogram (IVP) and the computed tomography (CT) scan with contrast.
Chronic urethral syndrome is characterized by symptoms suggestive of a lower urinary tract infection (such as pain and burning on urination, urinary urgency and urinary frequency) in the absence of significant bacteruria (voided urine is sterile or contains less than 100,000 bacteria per mL). In many of these women, spasm or irritability of the urethra (the tube connecting the bladder to the outside) can be demonstrated with urodynamic testing. There may also be concurrent elevation in pelvic floor muscle tension or even spasm. If these symptoms are prolonged then chronic pelvic pain may develop.