Differential Diagnosis for Very Itchy Follicular Rash

• Single Most Likely Diagnosis
  • Eczema (Atopic Dermatitis): This is a common condition characterized by itchy, inflamed skin, and can present with follicular involvement. The intense itch and the follicular nature of the rash make eczema a leading consideration.
• Other Likely Diagnoses
  • Keratosis Pilaris: A condition that causes small, rough patches on the skin, often with a follicular distribution, and can be itchy. It's common and fits the description of a follicular rash.
  • Folliculitis: An inflammatory condition affecting the hair follicles, often caused by bacterial or fungal infections. It can be very itchy and presents with follicular-based lesions.
  • Pityriasis Rosea: Although not always itchy, this condition can cause a follicular rash, especially in the initial stages. It's characterized by a herald patch followed by a widespread rash.
• Do Not Miss Diagnoses
  • Scabies: Caused by a mite, scabies leads to intense itching and can present with follicular burrows. Missing this diagnosis can lead to prolonged suffering and transmission to others.
  • Syphilis (Secondary): Can cause a variety of skin rashes, including follicular ones, and is critical to diagnose due to its serious long-term consequences if left untreated.
• Rare Diagnoses
  • Darier's Disease: A rare genetic disorder that affects the skin and can cause follicular rash among other symptoms. It's less common but should be considered in persistent cases without a clear diagnosis.
  • Phrynoderma (Toad Skin): A condition that can cause a follicular rash, often associated with nutritional deficiencies or environmental factors. It's rare and might be considered in cases where common diagnoses are ruled out.