21/11/2025
What is Cellulitis?
Cellulitis is a common but potentially serious bacterial infection of the skin and the deeper tissues beneath it (the dermis and subcutaneous fat). If left untreated, the infection can spread to the lymph nodes and bloodstream, becoming life-threatening.
The affected skin typically becomes swollen, red, warm, and tender. It most commonly occurs on the lower legs, but it can appear anywhere on the body.
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# # # Causes and Risk Factors
* **Cause:** The vast majority of cellulitis cases are caused by two types of bacteria:
* ***Streptococcus*** (usually group A *Streptococcus*)
* ***Staphylococcus aureus*** (including MRSA, Methicillin-resistant *S. aureus*)
These bacteria enter the body through a break in the skin.
* **Common Points of Entry:**
* Cuts, scrapes, or surgical incisions
* Puncture wounds (e.g., from a nail or bite)
* Insect or animal bites
* Dry, cracked skin, especially from eczema or athlete's foot
* Ulcers (e.g., diabetic or venous stasis ulcers)
* **Risk Factors (Who is more likely to get it?):**
* **Weakened Immune System:** From conditions like diabetes, HIV, or chemotherapy.
* **Skin Conditions:** Eczema, athlete's foot, or shingles which create breaks in the skin barrier.
* **Chronic Swelling (Lymphedema):** Often in the arms or legs after surgery (e.g., mastectomy) or due to other conditions.
* **History of Cellulitis:** Having had it once increases the risk of it returning.
* **Obesity**
* **Intravenous Drug Use**
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# # # Symptoms
Symptoms often start small and then spread rapidly. They can include:
* **Skin Redness:** The area becomes red and this redness tends to expand.
* **Swelling:** The affected area is swollen and puffy.
* **Tenderness and Pain:** The area is sore to the touch.
* **Warmth:** The skin feels warm or hot.
* **Fever and Chills:** A sign that the infection is becoming systemic.
* **Skin Dimplin
