The rash with mucosal ulceration.

A rash is a disseminated eruption of cutaneous lesions with great variation in appearance, cause, and severity. When the physician is facing a rash, the history and physical examination of the patient are extremely important for the identification of the disease and its causal agent. There are various causes for a rash, which may be infectious, allergic, or rheumatologic, besides many others. Rashes associated with mucosal ulcers may have causes related to viral and bacterial infections or drug reactions. They may be associated with measles; erythema infectiosum; roseola infantum; rubella; hand, foot, and mouth disease; pityriasis rosea; dengue fever; chikungunya; zika; scarlet fever; meningococcal diseases; syphilis; and exanthematous drug eruptions.