Correction: Insulin Pumps story

Insulin pumps are the size of a cell phone and worn on a belt or pocket. They send insulin into the body through a plastic tube with a small tip that inserts under the skin and is taped in place. They cost about $6,000 and supplies run $250 a month. Most health insurers cover much of the cost.

Users must tell the device how much insulin to give before each meal, based on the estimated carbohydrates in the meal. The devices also deliver a continuous low level of insulin.

In the FDA study, appearing in the May issue of the journal Pediatrics, the reports of adverse events and deaths in adolescents using the pumps occurred from 1996-2005.

The FDA requires manufacturers to report injuries that could be linked to medical devices. The authors analyzed reports from patients 12 to 21 years old. They emphasized that the reports aren't always clear about the cause of death or injury.

The devices provide an alternative to multiple daily injections of insulin by syringe; some come with glucose monitors that reduce the number of times the finger must be pricked to test blood sugar.

While some teenagers want to switch from insulin injections to pump therapy to gain more flexibility in their lives, doctors said device problems such as a blocked tube can lead quickly to dangerous episodes of high blood sugar.

"In a matter of a few hours, all the insulin in the body disappears. Metabolically, the child starts to spiral out of control," said Dr. John Buse, the American Diabetes Association's president for medicine and science. Kids need to be aware of the risk, monitor their blood sugar and be ready to give themselves an insulin injection.

Dr. Christina Luedke of Children's Hospital Boston said she carefully screens teenagers and their families before prescribing a pump. She has refused it for some young patients.

"Without appropriate glucose monitoring, the pumps can increase the risk of getting sick more quickly compared to injections," Luedke said. However, she said, proper use makes life more bearable and can improve glucose control.

Teenagers also have problems keeping their diabetes under control with multiple daily insulin injections, doctors and manufacturers said.