As far as can be determined, these diseases are triggered by immune reactions to congenital or antigenic agents. Protein acts like a sponge, and as it decreases in the body, osmotic pressure decreases, causing water to be absorbed and retained in protein molecules. Eye and ear infections are somewhat common. Urethritis is an infection of the urethra. Cystitis occurs when infections of the urethra go untreated and spread to the bladder.
Women are most susceptible to urinary tract infections because of the short urethra.
Scar tissue on the wall of the urethra or of the bladder after an infection may make someone more susceptible to future infections. Hygiene, diet, stress, and intercourse can contribute to cystitis. It may be caused by congenital factors such as a misshapen urethra. Bacteremia is relatively common as side effect of infection, after surgery, or when using intravenous drugs. Symptoms vary widley, and include fever, wide variations in urine volume, nausea, vomiting.