Several children in Florida experienced allergic reactions after they secretly ate chocolate during an Easter egg hunt, without their parents realizing it, according to a new report of the cases.
The four children — two boys and two girls, ages 4 to 7 years old — had all previously been diagnosed with a nickel allergy, a condition in which people experience skin rashes when they come in contact with the metal. Because the children appeared to be highly allergic to nickel — they still experienced body-wide rashes even when they tried to avoid contact with it — they were also instructed to avoid foods containing traces of nickel, including chocolate, peanut butter, oats and processed American cheese.
In each child's case, their symptoms had improved for two to five months, but then they all wound up at the doctor with flare-ups about two to five days after that year's Easter Sunday.
"They all came in on the same two-day period," said Dr. Sharon Jacob, a dermatologist who treated the children at the University of Miami. "That was what was strange. We thought, there's some common denominator here."
The parents all said their children had adhered strictly to the recommendation to avoid nickel-containing foods, and had not come into contact with objects containing the metal, said Jacob, who now works at Loma Linda University Medical Center in California.
But in each case, when a doctor asked the child a few follow-up questions, each one admitted "to having binged on chocolate during their Easter egg hunts, without their parents' knowledge," the researchers wrote in the March/April issue of the journal Pediatric Dermatology. [ 8 Strange Signs You're Having an Allergic Reaction ]
Nickel allergies are a common cause of contact dermatitis, an itchy skin rash that occurs after contact with a particular substance, according to the Mayo Clinic. In about 1 to 10 percent of nickel allergy cases, a rash may also be triggered by ingesting certain foods, Jacob said.
Although the researchers said they still cannot be certain that the children in the study consumed chocolate (because there were no parents around), the kids' confessions "strongly suggested this association in a time frame that coincided with a heavily chocolate-focused holiday: Easter," the researchers said.
Because Jacob saw four cases in just her area after Easter, she said she suspects that cases may be happening in other places but are not being reported. Often, people suspect that patients have eczema when they actually have a nickel allergy, Jacob said.
With continued oversight by the parents, the children's skin rashes went away. One year later, one of the children experienced another flare-up, after eating an entire chocolate bar.
"Clinicians should be aware of the potential for foods high in nickel to provoke patients with known nickel sensitivity and systemic dermatitis," the researchers said.
The researchers recommend that patients with nickel allergies consider restricting chocolate in their diets if they still have widespread rash symptoms even after avoiding contact with nickel-containing objects.
And they may have to avoid other foods in their diets, such as sunflower seeds, granola with raisins and pinto beans, which also contain trace amounts of nickel. Doctors recommend that patients first focus on restricting a few foods that they used to eat that contain nickel, and expand the number of foods if they continue to experience rashes.
Doctors can then follow up with patients to see how well the diet is working, and see if other foods need to be avoided.
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