Low vitamin D common in kids with cystic fibrosis

NEW YORK (Reuters Health) - Vitamin D deficiency is prevalent in children with cystic fibrosis (CF) and current treatment recommendations for correcting the deficiency are "inadequate," conclude clinicians from The Johns Hopkins Medical Institutions in Baltimore, Maryland.

They reviewed the charts of 262 children with CF patients treated at Johns Hopkins between 2003 and 2006 and found that vitamin D deficiency has declined but is still high; the prevalence was 86 percent in 2003 and 46 percent in 2006.

Many vitamin D deficient children remained deficient, despite getting "restorative" doses of vitamin D equal to or higher than the recommendations set by the Cystic Fibrosis Foundation, Dr. Deanna Green and colleagues report in the Journal of Pediatrics.

CF is a genetic disorder marked by the body's inability to transport chloride in and out of cells, causing mild to life-threatening complications, including recurrent and severe lung infections and delayed growth. Growing children with CF are especially vulnerable to vitamin D deficiency because a hallmark of the disorder is poor absorption of nutrients and malnutrition.

The recommended treatment dose for vitamin D deficiency is 50,000 international units (IU) of ergocalciferol (a form of vitamin D) once per week for 8 weeks for children 5 years of age or older and 12,000 IU once per week for 8 weeks for children younger than age 5 years.

But the Hopkins team that 50,000 IU per week of ergocalciferol for 8 weeks was effective in only 33 percent of the children with vitamin D deficiency, while increasing the dose to twice a week was effective in only 26 percent of children. Delivering the same dose 3 times a week corrected the deficiency in just 43 percent of children.

As a result of the findings, Johns Hopkins has amended its treatment protocol and now treats both adult and pediatric CF patients who have vitamin D deficiency with 50,000 IU ergocalciferol everyday for 4 weeks, according to a university-issued statement.

"These findings are a big wake-up call not only because they show that many children with CF are lacking vitamin D, but also because the deficiency persists even in those children who are treated with weekly doses twice or 3 times as high as the current recommendations," Green said.

"Clearly there is an urgent need to find more effective ways to restore healthy vitamin D levels," she concluded.

SOURCE: The Journal of Pediatrics, October 2008.