Cystitis is inflammation of the urinary bladder. Bladder becomes inflamed for many reasons, but the most common cause is urolithiasis, urinary sand that results from mineral crystals precipitating out of the urine and forming gritlike material. This grit or sand irritates the bladder wall and causes bleeding and straining. Cystitis due to the formation of urinary sand can occur in both male and female cats, but is much more serious when it occurs in males because the crystals often produce a dangerous obstruction in the male cat's narrow urethra. Less common cause of cyctitis is a bacterial infection, tumor, and the formation of bladder stones, which can become quite large and may have to be removed surgically.
Your cat may continually attempt to urinate while producing a few drops of urine each time. The urine may contain blood clots or fine crystalline "urinary sand." The urine color may vary from dark yellow to pink to extremely bloody. Your cat may continually lick his or her genitals. Provide your cat with fresh water to encourage drinking, which helps to flush the bladder of crystals and any bacteria that may be present. Increasing your cat's water consumption also helps to create a more dilute urine, which tends to produce less of a burning sensation during urination. Voiding frequently also allows less time for urine to become alkaline and, therefore, for further "grit" to form.
Clean your cat's litter box daily and change the entire box every 3 to 7 days in order to make her litter box as welcoming as possible. Some cats are very fastidious and hesitate to urinate in a somewhat dirty litter box. Feed your cat a high-quality, acidifying diet. Test your cat's urine periodically with special test strips (available from your vet or drugstores) to identify, with the help of your vet, when the acidity of the urine is at its best level. Vitamin C in the form of ascorbic acid, when given daily in moderate doses, can help maintain the urine's proper acidity, which, in turn helps prevent crystal formation and precipitation into urinary sand. Don't take your cat's daily elimination behavior for granted, observe it as often as possible.