Ecthyma n. : A cutaneous eruption, consisting of large, round pustules, upon an indurated and inflamed base.

Example:
What is the difference between Ecthyma and pyoderma?

Taxonomy
skin, skin infection, Ecthyma gangrenosum, impetigo, symptoms, blister, doctor, treatment, MedlinePlus Medical Encyclopedia, scratch, staphylococcus bacteria, ulcer, intravenous antibiotics, Philadelphia, Pa, urac, medical emergency, diagnosis, medical condition.

Defination from the web:
Ecthyma is most often caused by the bacteria streptococcus. Sometimes, staphylococcus bacteria causes this skin infection. ... The main symptom of ecthyma is a small blister with a red border that may be filled with pus. ...