Differential Diagnosis for Conjunctivitis with a Rash
- Single most likely diagnosis
- Adenoviral conjunctivitis (also known as pharyngoconjunctival fever): This is a common cause of conjunctivitis that can be accompanied by a rash, particularly in children. The rash is often mild and may resemble a viral exanthem.
- Other Likely diagnoses
- Allergic conjunctivitis with atopic dermatitis (eczema): Patients with atopic dermatitis can develop allergic conjunctivitis, which may present with a rash on the skin and conjunctival inflammation.
- Herpes simplex virus (HSV) infection: HSV can cause conjunctivitis and skin lesions, including a rash, particularly in the periorbital area.
- Varicella-zoster virus (VZV) infection: Chickenpox (varicella) and shingles (zoster) can cause a rash and conjunctivitis, especially if the rash involves the face.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Meningococcal infection: Neisseria meningitidis can cause conjunctivitis and a rash (purpura) as part of a severe, life-threatening infection. Prompt recognition and treatment are crucial.
- Rocky Mountain spotted fever (RMSF): This tick-borne illness can cause conjunctivitis, rash, and severe systemic symptoms. Early diagnosis and treatment are essential to prevent mortality.
- Rare diagnoses
- Kawasaki disease: A rare condition that primarily affects children, characterized by fever, rash, conjunctivitis, and other systemic symptoms. It is essential to consider this diagnosis to initiate appropriate treatment and prevent complications.
- Erythema multiforme: A skin condition that can cause a rash and conjunctivitis, often in response to an infection or medication. While rare, it can be severe and requires prompt recognition and management.