Dukes’ return? On the trail of the mysterious rash in school children

Is our current epidemic a reappearance of Dukes’ disease or “fourth disease?”

In the July 14, 1900, edition of The Lancet on page 89, an article appeared entitled, “On the confusion of two different diseases under the name of rubella (Rose Rash),” by Dr. Clement Dukes. In this article, Dukes reports the outbreak of an exanthematous disease at the Rugby School where he was senior physician. He argues for the existence of a new disease that he believes previously had been confused with rubella. Sound familiar?

During the past few months, we have experienced an epidemic of erythematous rash affecting mainly schoolchildren. This disease appears not to be fifth disease, which many thought it might be.

Philip A. Brunell, MD
Philip A. Brunell

The illness that Dr. Dukes described was subsequently designated “fourth disease.” However, the disease then disappeared, or did it? Is our current epidemic a reappearance of Dukes’ or fourth disease? The March 1 MMWR published a report entitled “Rashes among schoolchildren” — 14 States, October 4, 2001 – February 27, 2002.” The rash appeared to be “widespread in distribution” both in terms of the areas of the body involved and in the areas of the United States where it has occurred. It so far has affected mainly elementary schoolchildren, although a few middle, high and preschool children and some adults also have been involved.

In the cases described, there appeared to be little secondary spread in households. In two elementary schools, about 10% of the children appeared to be involved, while in a middle school about 25% were affected. The age distribution suggests to me that this very likely is an infectious disease that, as is true of many viral infections, has a high subclinical attack rate in the very young and tends to be more severe, ie, produces a rash, in older susceptible individuals. Most of the population probably is immune by virtue of having had subclinical cases when very young. The epidemiology is similar to that of infectious mononucleosis.

What we need to learn is the agent responsible and be able to assure pregnant women who get the disease that it will not affect their fetuses.

In general, the illness doses not appear to produce many systemic signs. It is characterized by a generalized rash, which is difficult to characterize from the reports. I was taught in dermatology to describe the distribution of the rash and more often than not, it will suggest the diagnosis. It is described as being on the “face, neck, hands, or arms” in one school, and in a second school as beginning on the face and spreading to the arms with exposed skin being mainly affected. In a third school it reportedly affected cheeks and arms, and another report described involvement of the trunk and extremities.

The rash is described as maculopapular erythematous highly pruritic, “reddish welty itchy … with smooth pink cheeks, bright red itchy or burning and macular, occasionally with an urticarial component.” The report continues with descriptions of the rash as “bright-red, itchy or burning and macular, occasionally with an urtical or papular component (pretty much covers all the bases), itchy and had a sunburned appearance” and “erythema and pruritis.”

Most described the onset as acute, lasting from a few hours to a few weeks. At this point one would call for help from the dermatologist. A group of dermatologists did examine one group of children and thought that it resembled fifth disease but had many atypical features.

Is this a return of the long absent Dukes’s disease or did Dukes’ disease never exist? Dr. Dukes’ job was much simpler in that he got to see all the cases at the Rugby School. However, he did not have the advantage of confirmatory laboratory tests that we now enjoy. Dukes’ problem was complicated by the presence of rubella and the coexistence of a scarlet fever epidemic. As scarlet fever has become relatively uncommon over the years and rubella virtually eliminated by vaccination, our concern was fifth disease. Children in a number of the school outbreaks have been tested for parvovirus B19, and this has been uniformly negative.

The most compelling argument for the existence of fourth disease as a separate illness was that children had rubella or scarlet fever either previously or subsequent to fourth disease. The coexistence of scarlet fever in the school may have obfuscated the description of fourth disease. The fever and desquamation of the rash, which was observed in some of the boys and the two deaths, may have been due to scarlet fever and not to fourth disease. The rash Dukes described in fourth disease was the first symptom to attract the attention of the sufferer, and “... in nearly every case was very full and quite characteristic of scarlet fever.”

It still is unclear whether our current epidemic is the return of Dukes’ disease or whether that disease actually existed. Giving it a different name (pseudo or para Dukes’ disease) would not be helpful. What we should perhaps carry away from this experience is that the illness is mild, and there does not appear to be any need to exclude children from school. What we need to learn is the agent responsible and to be able to assure pregnant women who get the disease that it will not affect their fetuses. Dukes certainly would have had sympathy for our plight as he offered that the diagnosis of these rash diseases “has bewildered and misled many of the ablest physicians.”