Highlights from the annual meeting of the American Academy of Allergy, Asthma and Immunology, San Antonio, February 22-26, 2013

By Nathan Seppa

Web edition: February 26, 2013
Print edition: March 23, 2013; Vol.183 #6 (p. 19)

Promising treatment for years-long hives
People with hives that recur for years and even decades might get relief from an allergy drug. Called omalizumab and marketed as Xolair, the drug inhibits the rogue antibody immunoglobulin E, which brings on persistent, intense itching and body-covering hives in some people. Scientists randomly assigned 323 patients with chronic hives, also called urticaria, to get three shots of the medicine spaced four weeks apart. One-quarter of them got a placebo while the others received one of three doses of the drug. Patients getting the two highest doses experienced substantial declines in itching that lasted until four weeks after the last shot, and 40 percent of the highest-dose group saw their hives disappear completely during treatment, said study coauthor Thomas Casale, an allergist at Creighton University in Omaha, Neb. Twelve weeks after the last shot, symptoms had started to return in most patients. Even so, said allergist and coauthor Allen Kaplan of the Medical University of South Carolina in Charleston, omalizumab could offer respite for patients with chronic hives. Roughly half fail to benefit from antihistamines at some point, as did everyone in this trial. “Many of us in the field view [omalizumab] as a game changer for these patients,” Kaplan said. The researchers reported the finding February 24 at the meeting and in the New England Journal of Medicine.  

Allergic kids’ growth at risk
Children with an allergy to dairy products weigh less on average than kids who can eat what they want, researchers at the University of North Carolina at Chapel Hill reported February 24. The scientists analyzed medical records of 245 food-allergic children up to age 11 and took note of any food allergies diagnosed from 2007 to 2011. Several allergies showed up— to peanuts, eggs, dairy and other foods. Overall, the children with more than two food allergies were slightly shorter than other children without food allergies. But only allergy to milk was undoubtedly linked to lower body weight, and this association was most striking in children who were younger than two years old, said study coauthor Caroline Hobbs, a pediatrician. Such children should receive special care, she said. “By that I mean dietary intervention — referral to a nutritionist or dietary counselor of some sort — to create diet alternatives.”

Vitamin D may boost hepatitis B shot
Compared to men with low levels of vitamin D, men with high levels might get more out of a hepatitis B vaccination, South Korean researchers reported. Scientists obtained blood samples from 5,025 men after they got immunized against hepatitis B. When the researchers divided the men into groups with low, medium or high levels of vitamin D, they found those in the low group had made much less protective antibody against hepatitis than did those in the high vitamin D group, Ju-Suk Lee of Sungkyunkwan University in Changwon reported on February 23. The findings jibe with other evidence that vitamin D helps regulate immune function. Men who smoked, were older, had diabetes or were heavier also had a muted response to the vaccine. Taken together, the analysis suggests that those factors might have a stronger negative effect on vaccination benefit than low vitamin D levels do.