Atlanta -- The so-called mystery rash is getting more mysterious. In fact, the Centers for Disease Control and Prevention says the hubbub played up in local and national media might be unfounded.

U.S. dermatologists have moved quickly to pinpoint the perplexing pediatric cutaneous conditions that have presented in 14 states across the country since October. The CDC, however, said that recent incidence of rash among hundreds of school-aged children across America does not represent an outbreak.

According to Rhonda Smith, a spokesperson for the CDC, evidence is not at hand to isolate a common cause for the rashes. The only similarity among them at the moment is "that they are unexplained," she said.

"It's not like a single rash is spreading across the country," Smith added. "We're simply not able to say that it is a single rash because we have no evidence of it. It's not the case at all. Our primary goal is to collect data, and we're trying to determine similarities and a possible common cause.

"The cause has not yet been identified. But at the same time there are always unexplained rashes, and sometimes they are only coincidentally similar. So that's a very real possibility."

So for now, the "mystery rash" remains a mystery.

Norman L. Sykes, M.D., the Pennsylvania-based dermatologist who has spearheaded efforts to define similarities and isolate a common cause for the rash, said 17 states, including his own, have reported some type of rash outbreak -- all presenting primarily in elementary school students.

Rashes about the face, arms, and legs presented in school children, and environmental testing in schools proved negative. Children offered no systemic symptoms, and the rash usually disappeared in a speedy fashion. The reports have been consistent around the United States.

"I've never seen anything like it in my practice," Dr. Sykes said. "Very interesting is that hundreds of more children elsewhere present the same baffling condition." Reports have it that in different locales from 10 to 600 children at a time have reported such a mysterious rash.

Dr. Sykes had new information to share from testing and skin-biopsy results on his patients. Patients continue to present to him with a rash. Some school-aged children have seen him more than once, and include some who first saw him in late January.

Lacking evidenceDr. Sykes reported there is no evidence of parvovirus B-19 in 30 rash patients who have undergone extensive blood testing, meaning the outbreak is not the common pediatric condition, fifth disease.

Multiple-stage skin biopsies in 10 patients revealed no irritating causal event, ruling out contact dermatitis. Dr. Sykes also said there is no evidence of it being eczema.

Preliminary results point to the rash having a foundation consistent with a viral infection, Dr. Sykes concluded. He added the condition could be an enterovirus or coxsackie virus. However, systemic symptoms of enterovirus haven't presented in patients, who seem to get only a rash that disappears within a few days to a week.

"We're casting a broad net to find out what is causing this rash," Dr. Sykes said.

The condition has the look and feel of parvovirus, Dr. Sykes said. The most likely possible common cause still is that the rash is a symptom of a new strain of parvovirus B-19, he added.