Persistent unpleasant sensations attributable to the bladder, can include pressure, spasms, or discomfort
Most frequent symptom is increased discomfort with bladder filling and relief with voiding
Symptoms usually constant but can vary from day to day and range from mild to severe
Location is usually suprapubic or urethral, but may also be unilateral lower abdominal pain or low back pain
Typically gradual onset over months
Most patients cannot identify a triggering event, but some patients note onset after a UTI, surgical procedure, or trauma
Exacerbation of symptoms can occur in the setting of stress, following intake of certain food or drinks, or after certain activities (e.g. sexual intercourse, exercise, sitting for a prolonged period), or during luteal phase of menstrual cycle
Interstitial cystitis
Bladder, urethral, or genital tract cancer
Acute cystitis
Urinary Tract Infection 
Pyelonephritis
STI
Prostatitis
Benign pelvic mass