What is the differential diagnosis for a non-blanchable purpuric rash?

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Differential Diagnosis for Non-Blanchable Perennial Rash

Single Most Likely Diagnosis

  • Eczema (Atopic Dermatitis): This is the most common cause of a non-blanchable perennial rash, especially in children. The rash is often itchy, and the skin can become thickened and scaly.

Other Likely Diagnoses

  • Psoriasis: Characterized by well-defined, red, scaly plaques, psoriasis can cause a non-blanchable rash, particularly on the elbows, knees, and scalp.
  • Contact Dermatitis: This is a type of skin inflammation caused by contact with irritants or allergens, leading to a non-blanchable rash.
  • Seborrheic Dermatitis: A common skin condition causing a non-blanchable rash, typically on the face, scalp, and torso.

Do Not Miss Diagnoses

  • Meningococcemia: A life-threatening infection that can cause a non-blanchable rash (purpura), which is a medical emergency.
  • Rocky Mountain Spotted Fever: A tick-borne illness that can cause a non-blanchable rash, which can be fatal if left untreated.
  • Vasculitis: Inflammation of the blood vessels can cause a non-blanchable rash, which can be a sign of a serious underlying condition.

Rare Diagnoses

  • Kawasaki Disease: A rare condition that mainly affects children, causing a non-blanchable rash, fever, and other symptoms.
  • Stevens-Johnson Syndrome: A rare but serious disorder of the skin and mucous membranes, often caused by an adverse reaction to medication or infection.
  • Erythema Multiforme: A rare skin condition characterized by a non-blanchable rash, often triggered by infections or medications.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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