What is cellulitis?

Cellulitis is defined as an infection that occurs in the deep dermis and subcutaneous tissue. It is characterized by the rapid onset of swelling, redness, and warmth in the affected area, often accompanied by systemic symptoms such as fever. The underlying causative agents are typically bacteria, with Streptococcus and Staphylococcus species being the most common.

The deep dermis and subcutaneous tissue are layers of skin that lie below the epidermis, which is the outermost layer. The infection often arises from a breach in the skin barrier, which can occur due to various factors such as cuts, insect bites, or other types of skin trauma. The inflammation associated with cellulitis can lead to severe complications if not promptly treated, making it important for medical professionals to recognize the condition accurately and initiate appropriate antibiotics.

In contrast, the other options pertain to different skin conditions. An infection of the epidermis would refer to a superficial skin infection, rather than the deeper layers involved in cellulitis. A localized sting reaction is typically a result of envenomation and does not equate to a bacterial infection. Allergic dermatitis involves an immune response to allergens and presents differently than cellulitis, which is primarily an infectious process. Understanding these distinctions is crucial for