Differential Diagnosis for Full Body Itching
The differential diagnosis for full body itching is broad and can be categorized into several groups based on the likelihood and potential severity of the conditions.
- Single Most Likely Diagnosis + Dry Skin (Xerosis): This is often the most common cause of full body itching, especially in older adults or during dry weather conditions. Itching can be intense and is usually accompanied by visible dryness of the skin.
- Other Likely Diagnoses + Atopic Dermatitis (Eczema): A chronic condition characterized by itchy, inflamed skin. It can affect any part of the body and is often seen in individuals with a history of allergies or asthma. + Psoriasis: An autoimmune condition leading to thick, scaly, itchy patches on the skin. It can occur anywhere on the body and is associated with other systemic symptoms in some cases. + Urticaria (Hives): Characterized by itchy, raised welts on the skin, which can be acute or chronic. Causes can range from allergic reactions to infections or autoimmune conditions. + Allergic Contact Dermatitis: A type of skin inflammation caused by contact with irritants or allergens, leading to itchy, red skin.
- Do Not Miss Diagnoses + Hodgkin Lymphoma: Some patients with lymphoma may present with itching all over the body without any visible skin rash, making it a critical diagnosis not to miss. + Cholestasis: Itching can be a symptom of liver disease, particularly cholestasis, where bile flow is reduced or blocked. This condition can lead to severe itching without a rash. + Thyroid Disorders: Both hyperthyroidism and hypothyroidism can cause itching, although the mechanism is not fully understood. + Renal Failure: Uremic pruritus associated with chronic kidney disease can cause intense itching all over the body.
- Rare Diagnoses + Polycythemia Vera: A rare blood disorder that can cause itching, particularly after warm baths or showers, due to the release of histamine from basophils. + Neurological Conditions: Certain neurological disorders, such as multiple sclerosis or neuropathies, can cause itching sensations without a rash. + Parasitic Infestations: Though rare in many parts of the world, parasitic infestations like scabies or pediculosis can cause severe itching. + Drug Reactions: Some medications can cause full body itching as a side effect, either through an allergic reaction or another mechanism.
Each of these diagnoses has distinct features and associated symptoms that can help guide the diagnostic process. A thorough history, physical examination, and sometimes laboratory tests are necessary to determine the underlying cause of full body itching.