Differential Diagnosis for Rash on Hands and Feet
Single Most Likely Diagnosis
- Contact Dermatitis: This is often the most common cause of a rash on the hands and feet, resulting from exposure to allergens or irritants. The hands and feet are frequently exposed to various substances that can cause allergic reactions or irritation, making contact dermatitis a likely diagnosis.
Other Likely Diagnoses
- Eczema (Atopic Dermatitis): A chronic condition characterized by itchy, inflamed skin. It can appear on the hands and feet, among other areas, and is common in individuals with a history of allergies or asthma.
- 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 hands and feet are common sites for psoriatic plaques.
- Keratolysis Exfoliativa (Focal Palmoplantar Keratolysis): A condition characterized by the peeling of skin on the palms and soles, often due to excessive moisture, friction, or fungal infections.
Do Not Miss Diagnoses
- Secondary Syphilis: A systemic infection caused by the bacterium Treponema pallidum, which can cause a rash on the palms and soles. Missing this diagnosis can lead to serious complications if left untreated.
- Meningococcemia: A severe infection caused by Neisseria meningitidis, which can present with a rash on the hands and feet, among other symptoms. It is life-threatening and requires immediate medical attention.
- Rocky Mountain Spotted Fever: A tick-borne illness caused by Rickettsia rickettsii, characterized by a rash that can appear on the hands and feet, along with fever and other systemic symptoms. It is critical to diagnose and treat promptly to prevent serious complications.
Rare Diagnoses
- Pityriasis Rubra Pilaris: A rare skin disorder characterized by constant inflammation and scaling (exfoliation) of the skin, which can involve the hands and feet.
- Keroderma Blennorrhagicum: A rare skin condition associated with Reiter's syndrome, characterized by lesions on the hands and feet, among other symptoms.
- Hand, Foot, and Mouth Disease (HFMD): Typically seen in children, caused by viruses such as coxsackievirus A or enterovirus 71, leading to sores in the mouth and a rash on the hands and feet. While more common in pediatric populations, it can occasionally occur in adults.