Interstitial cystitis is an affection that is more frequently due to, and associated with, disease in some other part of the urinary tract, than to an acute cystitis becoming chronic. A patient suffering from renal calculus will almost certainly have chronic cystitis, so also will those suffering with obstructions of the urethra, or from vesical calculus. Its most frequent causes then are the following: Chronic retention of urine from obstructive disease of the urethra - in early and middle life this means stricture, in advanced age, hypertrophy of the prostate - ; atony of the bladder, occasionally paralysis, foreign bodies in the bladder, tumors; sometimes abnormal conditions of the urine itself, and lastly it exists as a sequel of the acute malady.
