Differential Diagnosis for a 3yo Toddler with Itchy Legs and Sleep Disturbance

• Single most likely diagnosis:
  • Eczema (Atopic Dermatitis): This is a common condition in toddlers, characterized by itchy, inflamed skin. The itchiness can be severe enough to disrupt sleep, and the legs are a common area of involvement.
• Other Likely diagnoses:
  • Allergic Contact Dermatitis: This condition occurs when the skin comes into contact with an allergen, causing an itchy rash. Common allergens include nickel, latex, and certain plants.
  • Insect Bites or Stings: Mosquito bites, flea bites, or other insect bites can cause itchy skin lesions, especially on exposed areas like the legs.
  • Dry Skin (Xerosis): Dry skin can be itchy, especially in dry environments or during the winter months. Toddlers may not be able to communicate their discomfort effectively.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
  • Neuroblastoma: Although rare, neuroblastoma can cause leg pain or discomfort, which may be perceived as itchiness. It's essential to consider this diagnosis to avoid missing a potentially life-threatening condition.
  • Leukemia: Leukemia can cause bone pain, which may be referred to as itchiness, especially in young children who may not be able to describe their symptoms accurately.
• Rare diagnoses:
  • Kawasaki Disease: This rare condition can cause skin lesions, including itchy rashes, although it's more commonly associated with fever, rash, and lymphadenopathy.
  • Scabies: Although not extremely rare, scabies is less common in toddlers and can cause intense itching, especially at night. It's essential to consider this diagnosis, especially if there's a family history or exposure to someone with scabies.