Differential Diagnosis for 77 Year Old Female with Vesicles and Itchy Periorbital Erythema

• Single Most Likely Diagnosis
  • Contact dermatitis: This is the most likely diagnosis given the presence of itchy vesicles on the hand that rupture, followed by itchy periorbital erythema. The lack of systemic symptoms such as fever or upper respiratory tract infection (URTI) symptoms supports this diagnosis, as contact dermatitis is a localized skin reaction often caused by allergens or irritants.
• Other Likely Diagnoses
  • Herpes zoster (shingles): Although less likely due to the absence of a typical dermatomal distribution and the presence of periorbital erythema without mention of a rash in the V1 distribution, herpes zoster could still be considered, especially in an elderly patient.
  • Atopic dermatitis (eczema): Given the itchy nature of the lesions and the involvement of the periorbital area, atopic dermatitis is a possibility, especially if the patient has a history of atopy.
  • Irritant contact dermatitis: Similar to contact dermatitis, but caused by exposure to irritants rather than allergens, this could explain the hand lesions if the patient was exposed to something irritating.
• Do Not Miss Diagnoses
  • Angioedema: Although the presentation is not typical, angioedema can cause periorbital erythema and swelling. It's crucial to consider this diagnosis due to its potential to cause airway obstruction, especially if there are any symptoms suggestive of laryngeal involvement.
  • Cellulitis or erysipelas: Infection should always be considered, especially in elderly patients, as it can present atypically. The absence of fever does not rule out infection, and the periorbital erythema could be a sign of spreading infection.
• Rare Diagnoses
  • Autoimmune bullous dermatoses (e.g., pemphigus, pemphigoid): These conditions are rare and typically present with more widespread blistering, but could be considered if the diagnosis remains elusive after thorough investigation.
  • Phototoxic or photoallergic reactions: If the patient has been exposed to certain medications or substances and then to sunlight, a phototoxic or photoallergic reaction could occur, although the pattern of involvement would typically be more suggestive of sun-exposed areas.