Differential Diagnosis for Intense Itching of Chest
- Single most likely diagnosis
- Aquagenic pruritus: This condition is characterized by intense itching after exposure to water, without any visible rash. The patient's symptoms of intense itching after showering, with no other symptoms or rash, make this a plausible diagnosis.
- Other Likely diagnoses
- Dry skin (xerosis): Showering can strip the skin of its natural oils, leading to dryness and itching, especially in individuals with a history of substance use, which may affect skin health.
- Allergic reaction to soap or shampoo: Although the patient denies an association with substance use, an allergic reaction to a new or recently changed soap or shampoo could cause itching after showering.
- Cholinergic urticaria: This condition is caused by an increase in core body temperature, which can occur after a warm shower, leading to itching and hives, although the patient does not report any rash.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Polycythemia vera: This rare blood disorder can cause itching after exposure to water (aquagenic pruritus) due to the release of histamine from mast cells. Although unlikely, it is essential to consider due to its potential severity and the need for prompt treatment.
- Thyroid disorders: Both hyperthyroidism and hypothyroidism can cause itching, and although the patient does not report any other symptoms, it is crucial to rule out these conditions due to their potential impact on overall health.
- Rare diagnoses
- Mastocytosis: A rare condition characterized by an accumulation of mast cells in the skin, which can cause itching, flushing, and other symptoms after exposure to water or temperature changes.
- Erythromelalgia: A disorder that affects blood flow to the skin, causing burning, itching, and heat sensations, which can be triggered by warm water or temperature changes.