Bladder Control - Aggressive Toy Truck Behaviour as a Response to an Overfull Bladder in a Toddler.

A 3.5 year-old boy who was referred for voiding frequently. He stopped wearing a day diaper at about 3 years of age and since then he peed as often as every 15 minutes. Mom mentioned that the prior night he needed to pee 5 times during a 45-minute dinner at a local restaurant. He was mostly dry at night but only because he routinely woke up to pee between 2 and 5 AM. Holding postures and urgency were not common and daytime wetting was only once every three weeks. There were no other symptoms to suggest urine infection and his urine tests at the family doctor and in my office did not show infection. Mom told me he pooped every day, later in the day, and he pushed to poop. He doesn’t drink much.

This is the story of a boy who is more attentive to bladder signals than most of his peers and who has a small bladder capacity. In the absence of bladder infection, a small bladder capacity is usually due to the presence of hard or pasty poop that presses into the bladder. The pelvis in a child is not very big. The bones of the pelvis are a shaped like a funnel and the bladder and the bowel are compressed side-by-side into the most narrow portion at the bottom. The bladder is "at the mercy" of solid stool and cannot push the poop out of the way.

He arrived as a happy well-behaved boy and he cooperated to drink enough water that his bladder filled up five times over the two hours in my office. He played in the room where I talked with Mom for the first three voids and in each case his personality changed as his bladder filled up and then progressed to an overfull situation. He had a big red truck, which he manoeuvred around on the floor.

The following sequence of events played out in response to his overfull bladder. He stopped using the truck and stood up. He touched his groin with his hand (signal that bladder is full). Then he resumed playing. Within a minute he was aggressive with the truck. On the first occasion he kicked the truck. After the display of aggression and Mom’s comment to “play nice,” he stood up, touched his groin, and announced that he needed to pee. I pointed out to Mom that the behaviour change was a response to an overfull bladder and she didn’t believe me, but when the same sequence played out the second time (this time he ran the truck into the wall) and third time (he ran the truck into the exam table), she understood my observation was correct. Part of my job is helping parents to recognise the signs of an overfull bladder in their child.

Children would rather play than pee and the decision to ignore a full bladder is real easy, but the brain does not ignore the increasing bladder filling and the brain signals are often expressed with a personality change that is unique for every child.

No one should ever ask a toddler, pre-school, or early elementary school-aged child to hold his or her pee. Parents should make sure to build in lots of opportunities to pee to prevent an overfull bladder. 

A full bladder or bowel is not the only event that can trigger a change in behaviour. Lack of sleep and a low blood sugar are other possible triggers.

When the behaviour of a child changes, a parent should consider asking the child to pee.