Cystitis refers to symptoms such as frequent urination, urgent urination, painful urination, hematuria, and even lower abdominal pain caused by infections from bacteria, viruses, mycoplasma, chlamydia, etc. The most common cause is bacteria entering the urethra through the urethral opening and spreading to the bladder. Additionally, kidney diseases such as pyelonephritis can also cause cystitis. Bacteria from the remaining infected urine produced by pyelonephritis travel down the ureters into the bladder, thus causing cystitis. After contracting cystitis, it is necessary to receive timely anti-inflammatory treatment, and generally, the condition can be healed with about a week of medication.