Differential Diagnosis for Shingles on Stomach
Single most likely diagnosis
- Postherpetic itch: This is the most likely diagnosis given the history of shingles (herpes zoster) on the stomach 2 weeks ago that has now dried but remains very itchy. Postherpetic itch is a common complication of shingles, occurring after the rash has resolved.
Other Likely diagnoses
- Dry skin (xerosis): The dryness of the skin after the shingles rash could contribute to itchiness, especially if the skin is not properly moisturized.
- Contact dermatitis: If the patient has applied any topical treatments or used certain soaps that irritate the skin, contact dermatitis could be a contributing factor to the itchiness.
- Eczema (atopic dermatitis): Pre-existing eczema could be exacerbated by the skin changes following shingles, leading to increased itchiness.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Bullous pemphigoid: Although rare, bullous pemphigoid is an autoimmune blistering disease that can present with intense itching and could be mistaken for a postherpetic complication. It requires prompt diagnosis and treatment to prevent serious complications.
- Cutaneous T-cell lymphoma (CTCL): This is a rare type of skin cancer that can cause severe itching. While unlikely, missing this diagnosis could have severe consequences.
Rare diagnoses
- Brachioradial pruritus: A rare condition characterized by intense itching of the skin, typically on the arms but can occur elsewhere, including the stomach. It's often associated with nerve damage.
- Notalgia paresthetica: A condition that causes itching on the back, but can occasionally occur on the stomach, due to nerve compression or damage.
- Aquagenic pruritus: A rare condition where contact with water induces intense itching without any visible skin lesions.