Urinary tract infections, commonly called UTIs, occur when bacteria infect one or several parts of the urinary system, including the kidneys, ureters, bladder and urethra. Kids Health explains that UTIs are common in young children but can occur in older children, too, including 13-year-old boys. Boys are less likely than girls to develop a UTI. Some symptoms of a UTI include pain, burning or stinging when burning and an increased urge to urinate.
E. coli is the most common cause of UTIs, according to Kids Health. The bacteria is found in the intestine and can be passed in the stools. When wiping after a bowel movement, the fecal matter can be moved near the penis. When the bacteria reaches the head of the penis it can enter the lower urinary tract and cause infection. A UTI caused by E. coli is more likely in girls due to the shape of the genitals.
An abnormally formed kidney or protrusion in the urinary tract can block urine, according to Kids Health. When urine remains in the urinary tract, bacteria can overproduce and lead to infection.
Urine reflux is an abnormal function of the urinary system. It occurs when urine flows back up from the bladder toward the kidneys. This is called vesicoureteral reflux, a condition present at birth. Kids Health indicates that 30 to 50 percent of children with a UTI are found to have this condition. Merck Manual explains that urine reflux conditions and other structural abnormalities are the most likely cause of UTIs in school-aged children.
Improper cleansing of the penis, especially when uncircumcised, can contribute to a buildup of bacteria on the head of the penis. Failing to rinse soap off the penis can also cause irritation that results in inflammation of the urinary tract.
Whether intentional or due to a condition, a teen boy who does not empty his bladder fully can end up with a UTI. Some brain or nervous system illnesses, such as those affecting the spinal cord, can make it harder for a boy to fully empty his bladder, according to the National Institutes of Health. Making infrequent trips to the bathroom or holding urine for prolonged periods of time can also lead to a UTI because bacteria can build up inside the tissues of the urinary tract.