The millions of civilians and tens of thousands of Gulf War veterans in the United States who suffer from chemical sensitivity should not be kept waiting any longer for a standardized diagnosis just because medical researchers do not yet fully understand the etiology of all their signs and symptoms. We would add only that symptoms associated with chemical exposures must involve multiple organ systems, in order to distinguish MCS from specifically single organ system disorders such as asthma and migraine that also may meet the first five criteria. The condition is chronic. The symptoms improve or resolve when the incitants are removed. Responses occur to multiple chemically unrelated substances.
Symptoms involve multiple organ systems.
MCS should be excluded only if a single other multi-organ disorder can account for both the entire spectrum of signs and symptoms and their association with chemical exposures, such as mastocytosis or porphyria, but not CFS or FM, which are not so associated. While no single test is yet considered diagnostic of MCS, those suggested by signs, symptoms or history may be helpful in treating and tracking the disorder. The presentation of MCS may vary greatly among cases and over time. Some individuals are totally disabled by severe symptoms suffered on a daily basis, for example, while others are disabled only minimally by mild symptoms suffered occasionally. For research purposes that require greater homogeneity, we encourage investigators to refine the Consensus Criteria for MCS with whatever additional inclusion or exclusion criteria they believe are needed to test their hypotheses.