Sixteen patients with an unusual and distinct symptom complex were encountered during a four-year period. Principal features of this syndrome are (1) fever lasting more than seven days; (2) conjunctival injection; (3) changes in the mouth consisting of erythema of the oropharynx, "strawberry tongue", and erythema of the lips; (4) indurative edema of hands and feet with palm and sole erythema followed by desquamation of the fingertips; and (5) an erythematous rash. Associated features were lymphadenopathy, pyuria, aseptic meningitis, diarrhea, arthritis, and arthralgia. Although usually a self-limited illness, one patient died with massive coronary artery thrombosis on the 19th day of illness. This syndrome appears to be clinically and pathologically similar to mucocutaneous lymph node syndrome, an illness prevalent in Japan but previously unrecognized by American clinicians. Pathologic features suggest a relationship to infantile periarteritis nodosa.