Differential Diagnosis for Nocturnal Itching
Single Most Likely Diagnosis
- Atopic Dermatitis (Eczema): This condition is characterized by dry, itchy skin and is often worse at night, leading to nocturnal itching. It's a common condition that can cause significant discomfort and sleep disturbance.
Other Likely Diagnoses
- Dry Skin (Xerosis): Dry skin can cause itching that worsens at night due to the lack of moisture in the environment and the natural decrease in moisture levels of the skin during sleep.
- Allergic Contact Dermatitis: This is a skin reaction that occurs after contact with an allergen, leading to itching, redness, and sometimes blistering. Nocturnal itching can be a symptom if the allergen is in bedding or clothing.
- Scabies: A parasitic infection caused by the mite Sarcoptes scabiei, leading to intense itching, especially at night. The itching is due to the mites burrowing into the skin.
- Flea or Bed Bug Bites: Bites from these insects can cause severe itching that may be worse at night, especially if the infestation is in the bedding.
Do Not Miss Diagnoses
- Lymphoma: Certain types of lymphoma, like cutaneous T-cell lymphoma, can present with itching as a primary symptom, including nocturnal itching. Although rare, missing this diagnosis could be fatal.
- Hodgkin Lymphoma: Itching (pruritus) can be an early symptom of Hodgkin lymphoma, and it may worsen at night.
- Cholestasis: Liver diseases that cause cholestasis, such as primary biliary cirrhosis, can lead to severe itching due to the buildup of bile salts in the skin. This itching can be worse at night.
- Thyroid Disorders: Both hyperthyroidism and hypothyroidism can cause skin changes and itching, which may be more noticeable at night.
Rare Diagnoses
- Polycythemia Vera: A rare blood disorder that can cause itching, especially after warm baths or at night, due to the release of histamine from basophils.
- Neurological Disorders: Certain neurological conditions, such as multiple sclerosis or peripheral neuropathy, can cause itching sensations without a clear skin rash.
- Psychogenic Itching: Also known as psychogenic pruritus, this is a condition where the itching is of psychological origin, without an identifiable skin cause. It can be challenging to diagnose and treat.