Final answer:
Impetigo is a contagious skin infection that causes vesicles, pustules, and bullae, typically around the nose and mouth, and is caused by Staphylococcus aureus and/or Streptococcus pyogenes. It can be nonbullous or bullous in form, and diagnosis is commonly based on appearance. Antibiotics are effective for treatment, but S. pyogenes-related impetigo can lead to serious complications.
Step-by-step explanation:
Impetigo is a type of skin infection characterized by the formation of vesicles, pustules, and possibly bullae, which are large, fluid-filled blisters. It typically occurs around the nose and mouth and is highly contagious. Impetigo can present in two forms: nonbullous, where vesicles and pustules rupture to become encrusted sores, and bullous, where large bullae fill with fluid and rupture, resulting in larger draining lesions. This bacterial infection is commonly caused by Staphylococcus aureus, Streptococcus pyogenes, or a combination of both, and is particularly common in children.
Diagnosis is often made by observing the skin's appearance, though culture and susceptibility testing may be performed as well. Topical or oral antibiotic treatment is typically effective. However, impetigo caused by S. pyogenes can potentially lead to serious complications such as acute glomerulonephritis (AGN).