What It Takes to Make a Diagnosis
In babies, the most frequent -- and often the only -- symptom is fever, though others can include foul-smelling urine, persistent vomiting, or diarrhea. Some babies may lose interest in eating. Toddlers and school-age kids may also have belly pain and may urinate frequently or complain that it hurts when they go.
The only way to be sure that an infant has a UTI is to perform a catheterization, as we did with Amber. In the past, some pediatricians would simply tape a plastic bag onto an infant's genitals, and collect urine whenever the child happened to pee. Today, most doctors realize that normal bacteria around the genitals contaminate the bag, making the results unreliable.
I know how upsetting these catheterizations are for parents, who usually need to help hold their child down as I insert the catheter. And though I first dip it in pain-numbing gel, studies have shown that doesn't reduce the discomfort much. Still, I try to explain that the procedure typically takes just a minute or two and is key to avoiding long-term kidney damage. (Some potty-trained older toddlers can urinate cleanly into a sterile cup, so a catheterization isn't always needed.)
Urine is normally clear, so if it's cloudy, we suspect a UTI. If the child is very uncomfortable, we may prescribe antibiotics while awaiting confirmation from the lab. Technicians will check for the telltale white blood cells found during infections. (That's what makes the urine cloudy.) Then they'll see whether any bacteria grow. If they don't, we stop the meds. But if they do, the lab worker will try to kill them with various antibiotics, and then report back within a day or two on which one worked best. That's how your doctor knows the best medicine to prescribe.