Differential Diagnosis of a Small Subepidermal Vesicle on a Finger Tip
Single Most Likely Diagnosis
- Herpes simplex virus (HSV) infection: This is a common cause of small, painful vesicles on the fingertips, often referred to as herpetic whitlow. The location and description of the lesion, along with potential symptoms like pain and itching, make HSV a prime consideration.
Other Likely Diagnoses
- Contact dermatitis: Irritant or allergic reactions to substances like detergents, solvents, or certain plants can cause vesicular eruptions on the skin, including fingertips.
- Dyshidrotic eczema (pompholyx): Characterized by small, itchy vesicles on the palms or soles, which can sometimes appear on the fingertips.
- Friction blisters: Repeated friction or pressure on the skin can lead to the formation of vesicles, especially in areas like the fingertips.
Do Not Miss Diagnoses
- Herpes zoster (shingles): Although less common on the fingertips, it's crucial to consider due to its potential for severe pain and complications like postherpetic neuralgia.
- Infections requiring prompt treatment: Bacterial infections (e.g., staphylococcal or streptococcal) that could lead to more severe conditions like abscesses or cellulitis.
Rare Diagnoses
- Bullous pemphigoid: An autoimmune disease that can cause blistering of the skin, though it's more common in older adults and typically involves larger areas of the body.
- Dermatitis herpetiformis: A skin manifestation of celiac disease, characterized by intensely itchy, blistering skin, which could potentially appear on the fingertips.
- Epidermolysis bullosa acquisita: A rare autoimmune disorder that results in blistering of the skin and mucous membranes, which might present with vesicles on the fingertips among other symptoms.