The bladder is part of the urinary tract, which consists of the bladder, the urethra, the kidneys and the ureters, which are tubes that urine travels through from the kidneys to the bladder. The urethra is the tube through which urine flows from the bladder to outside the body. A bladder infection falls under the umbrella term of a urinary tract infection (UTI). Bladder infections are more common in women than in men, because women have shorter urethras and bacteria can more easily reach the bladder because of the shorter distance. But men can get bladder infections, too, and the causes can vary.
Bacteria
The root cause of a bladder infection is bacteria. Bacteria from the digestive tract can remain at the end of the urethra and multiply. If the bacteria reach the bladder, a bladder infection can result. There are different ways for bacteria to reach the bladder and cause infection.
Partial Emptying of Bladder
The most common cause of bladder infections in men is the incomplete or poor emptying of the bladder. When the bladder is not fully emptied during urination, small amounts of urine remain in it. This urine creates an environment in which bacteria can multiply and result in infections. The most common cause of incomplete emptying of the bladder is an enlarged prostate. Because enlarged prostates are more common in men over the age of 50, bladder infections occur more frequently in men who are older than 50.
Unprotected Anal Sex
This can result in bacteria that normally reside in the bowels to reach the urethra. The bacteria can multiply and reach the bladder and cause a bladder infection. This type of bacteria can cause a bladder infection even though this type of bacteria causes no problems in the bowels.
Bladder or Kidney Stones
Some of these stones can carry bacteria, which can lead to a bladder infection. Also, these stones can cause blockage, which can result in the pooling of urine, as in the case of an enlarged prostate.
Weakened Immune System
People who have a weakened immune system, such as those undergoing chemotherapy treatments, are at higher risk for all types of infections, including bladder infections.
Narrowed Urethra
An abnormally narrowed urethra, which can occur as a result of surgery, infection, disease or the insertion of a catheter, increases the risks of a bladder infection.
