What is the cause of nodular prurigo?
The cause of nodular prurigo is unknown. It is uncertain whether scratching leads to the lumps, or if the lumps appear before they are scratched. The reason for the lumps, the inflammation and the increased activity and size of nerves in the skin is unknown. Up to 80% of patients have a personal or family history of atopic dermatitis, asthma or hay fever (compared to about 25% of the normal population). Nodular prurigo may commence as an insect bite reaction or another form of dermatitis. It has been associated with internal disease including iron deficiency anaemia, chronic renal failure, gluten enteropathy, HIV infection and many other diverse conditions.
