Differential Diagnosis for Skin Rash
- Single Most Likely Diagnosis
- Eczema (Atopic Dermatitis): This is a common condition characterized by itchy, inflamed skin. It's often seen in individuals with a history of allergies or asthma, and it can be triggered by a variety of factors including soaps, detergents, or environmental allergens.
- Other Likely Diagnoses
- Contact Dermatitis: An allergic reaction or irritation caused by contact with substances like metals (e.g., nickel), latex, certain chemicals, or plants (like poison ivy). Symptoms include redness, itching, and small blisters.
- Psoriasis: A chronic 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 itch or burn.
- Allergic Reaction: Could be due to medications, foods, or insect bites, presenting with hives, itching, and sometimes difficulty breathing.
- Do Not Miss Diagnoses
- Meningococcemia: A severe infection caused by Neisseria meningitidis, which can present with a rash (petechial or purpuric), fever, and potentially life-threatening complications if not treated promptly.
- Rocky Mountain Spotted Fever (RMSF): A bacterial infection transmitted by ticks, characterized by fever, headache, and a distinctive rash. It's critical to diagnose and treat RMSF early to prevent serious complications.
- Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis (SJS/TEN): A severe skin condition usually triggered by medications or infections, leading to blistering of the skin and mucous membranes. It's a medical emergency requiring immediate attention.
- Rare Diagnoses
- Pemphigus: A group of rare skin disorders that cause blistering of the skin and mucous membranes. It's an autoimmune disease where the body's immune system attacks healthy skin and mucous membrane cells.
- Kawasaki Disease: An illness that affects children and causes inflammation in the walls of medium-sized arteries throughout the body. It's characterized by fever, rash, swelling of the hands and feet, irritation and redness of the eyes, lips, throat, and tongue.
- Erythema Multiforme: An immune-mediated disorder characterized by target-like lesions on the skin, often triggered by infections (like herpes simplex) or medications. It can also affect the mucous membranes.