Differential Diagnosis for Conditions that Mimic Cellulitis
- Single most likely diagnosis:
- Contact dermatitis: This is a common condition that can mimic cellulitis, especially if it's an acute allergic reaction. The presence of a clear boundary and the absence of systemic symptoms can help differentiate it from cellulitis.
- Other Likely diagnoses:
- Eczema (atopic dermatitis): Eczema can sometimes be confused with cellulitis due to the redness and swelling. However, eczema tends to be more chronic and is often accompanied by intense itching.
- Psoriasis: Plaque psoriasis can cause red, scaly patches that might be mistaken for cellulitis, especially if the patient has not been diagnosed with psoriasis before.
- Stasis dermatitis: This condition occurs due to poor circulation and can cause skin changes that resemble cellulitis, including redness and swelling, typically in the lower legs.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed):
- Necrotizing fasciitis: Although rare, this is a life-threatening condition that requires immediate medical attention. It can present similarly to cellulitis but is characterized by severe pain out of proportion to the appearance of the skin, and systemic signs of infection.
- Deep vein thrombosis (DVT): DVT can cause swelling and redness in the affected limb, which might be confused with cellulitis. It's crucial to consider DVT, especially in patients with risk factors such as recent surgery, immobilization, or cancer.
- Rare diagnoses:
- Erythema nodosum: This condition causes tender red nodules under the skin, typically on the lower legs, and can be mistaken for cellulitis. It's often associated with underlying conditions such as infections, autoimmune diseases, or medications.
- Lipodermatosclerosis: A condition characterized by inflammation and scarring of the subcutaneous fat, leading to skin changes that might resemble cellulitis, especially in the context of chronic venous insufficiency.