Impetigo is a type of bacterial rash normally occuring on the face and extremities that progresses from papules to vesicles to pustules then crusts.  There are two main sub types of impetigo: non-bullous and bullous (caused by S. aureus that produces exfoliative toxin A).  The organisms that cause the rash are S. aureus and streptococci species.  Potential post infectious sequelae include poststreptococcal glomerulonephritis and rheumatic fever.  Diagnosis is usually made based on the appearance and description of the rash.  You can send fluid/pus cultures to confirm organism.  This is not routinely needed.  The recommended treatment is antibiotics either topical or oral.  Topical treatment is preferred to oral treatment.  Drug of choice is mupirocin applied three times per day.  Oral therapy needs to cover the causative organisms.  The following drugs are currently recommended cephalexin, clindamycin or linezolid until improvement of rash (~ 1 week) occurs.