In ecthyma the pustules are generally of the size of a split pea, and surrounded at their base by a broad halo of redness.
How would you differentiate the large flat-pustular syphiloderm from ecthyma?
Yet these cases were discriminated from smallpox; they were diagnosed, and have been recorded, as an epidemic of ecthyma.
ecthyma ec·thy·ma (ěk-thī'mə)
A pyogenic infection of the skin due to staphylococci or streptococci and characterized by adherent crusts beneath which ulceration occurs.