Chronic pruritus

Pruritus (lat. prurigo ) is defined as an unpleasant sensation of skin leading to the desire to scratch ( itch )

Common dermatological problem Often intractable with a high impact on quality of life Increases with ageEstimated that 60 % of people > 65 suffer from mild to severe occasional pruritus each week Exact prevalence is not known Can be caused by both skin and systemic problems International forum for the study of Itch has suggested a classification which considers clinical as well as differential diagnostic reasons

Systemic causes- Metabolic and Endocrine♦ Chronic renal insufficiency♦ hyperparathyroidism♦ hyper & hypothyroidism♦ Carcinoid syndrome♦ Diabetes Hepatic♦ PBC♦ Extrahepatic biliary obstruction♦ Cholestasis of pregnancy♦ Hepatitis♦ Oral contraceptives♦ Drug ingestion Infective disease♦ HIV and AIDS♦ Parasitoses including Helminthosis Haematological♦ Polycythemia vera♦ Myelodisplastic syndrome♦ Lymphoma eg Hodgkins lymphoma♦ Multiple myeloma♦ Iron deficiency Neurological disorders♦ Multiple sclerosis♦ Brain tumours ( eg gliomas )♦ Notalgia paraesthetica♦ Brachioradial pruritus♦ Peripheral neuropathy Psychiatric or Psychosomatic diseases♦ Depression♦ Affective disorders♦ Hallucinosis♦ OCD♦ Schizophrenia♦ Eating disorders

Dermatological causes-Xerosis Scabies Dermatitis herpetiformis Atopic dermatitis Lichen simplex Psoriasis Lichen planus Contact dermatitis Miliaria Drug reactions Insect bites Pruritic urticarial papules and plaques of pregnancy Peduculosis Urticaria Folliculitis Sunburn Polymorphous light eruption Bullous pemphigoid Pemphigus...