Differential Diagnosis for Rash in a Toddler
Single Most Likely Diagnosis
- Viral Exanthem (e.g., Roseola, Fifth Disease): This is the most common cause of rash in toddlers, often accompanied by mild symptoms such as fever and upper respiratory tract infection.
Other Likely Diagnoses
- Eczema (Atopic Dermatitis): A common skin condition in toddlers, characterized by itchy, inflamed skin, often related to allergies or asthma.
- Impetigo: A contagious bacterial skin infection, typically presenting with red sores or blisters that can burst and crust over.
- Contact Dermatitis: A skin reaction that occurs after contact with an irritant or allergen, resulting in redness, itching, and small blisters.
- Allergic Reactions (e.g., to food, insect bites): Allergic reactions can cause a range of skin symptoms, including hives, itching, and redness.
Do Not Miss Diagnoses
- Meningococcemia: A life-threatening infection that can cause a rash, often accompanied by fever, headache, and stiff neck.
- Kawasaki Disease: An acute illness that can cause a rash, fever, and lymph node swelling, potentially leading to cardiac complications if untreated.
- Staphylococcal Scalded Skin Syndrome (SSSS): A condition caused by staphylococcal toxins, resulting in widespread skin blistering and peeling.
Rare Diagnoses
- Juvenile Idiopathic Arthritis (JIA): A chronic autoimmune disease that can cause skin rashes, joint pain, and swelling.
- Lyme Disease: A bacterial infection transmitted by tick bites, which can cause a distinctive "bull's-eye" rash, fever, and headache.
- Congenital Infections (e.g., Congenital Syphilis, Rubella): Infections acquired during pregnancy, which can cause a range of symptoms, including skin rashes, in newborns and toddlers.