Differential Diagnosis for Arm Rash and Acute Pain in Wrist
Single Most Likely Diagnosis
- Cellulitis or Skin Infection: This is a common condition that can cause both a rash and acute pain, especially if the infection involves the wrist area. The rash can be red, swollen, and warm to the touch, and the pain can be severe.
Other Likely Diagnoses
- Contact Dermatitis: An allergic reaction or irritation from substances like soap, detergent, or certain plants can cause a rash and discomfort in the affected area, including the wrist.
- Eczema (Atopic Dermatitis): Characterized by itchy, inflamed skin, eczema can cause acute pain if the skin becomes severely inflamed or if there are open sores.
- Psoriasis: An autoimmune condition that speeds up the life cycle of skin cells, causing cells to build up rapidly on the surface of the skin. The extra skin cells form scales and red patches that can be itchy and painful.
- Insect Bites or Stings: Certain insect bites or stings can cause a rash and acute pain, especially if there is an allergic reaction.
Do Not Miss Diagnoses
- Septic Arthritis: Although less common, septic arthritis is a serious condition that requires immediate medical attention. It occurs when the joint space is infected, leading to severe pain, swelling, and potentially a rash if the infection spreads to the skin.
- Lyme Disease: Caused by a tick bite, Lyme disease can initially present with a characteristic "bull's-eye" rash and later cause joint pain, including in the wrists.
- Gout or Pseudogout: These conditions cause sudden, severe joint pain and can be accompanied by a rash if there is significant inflammation or if the patient develops skin lesions due to urate crystal deposition.
Rare Diagnoses
- Sarcoidosis: A condition that can cause inflammation in various parts of the body, including the skin and joints. It can present with a rash and joint pain, although this is less common.
- Vasculitis: Inflammation of the blood vessels can cause a variety of symptoms, including rashes and joint pain, depending on which vessels are affected.
- Erythema Multiforme: A skin condition characterized by target lesions, which can be triggered by infections or medications. It can cause a rash and, less commonly, joint pain.