Prurigo is a condition in which there are independent itchy papular/nodular eruptions induced by insect bite or allergy. These pruritic papules are thought to be an inflammatory response and are characterized by exudative inflammatory lesions that do not develop into the other types of eruptions e.g. psoriatic or eczematous lesions. Prurigo remains as chronic papules and nodules.
Acute Prurigo (Strophulus Infantum) is when urticarial erythema or wheals appear and become exudative papules, usually in small children. Secondary infection may be caused by rubbing and scratching brought on by intense itching.
Subacute prurigo (Prurigo Simplex Subacute) is when an urticarial papule accompanied by intense itching occurs on the extensor surface of the extremities or the trunk. When it is rubbed and scratched, erosion or crust forms.
A primary disease is often involved in Subacute Prurigo, for example, atopic dermatitis, diabetes, liver dysfunction, lymphoma, leukemia, Hodgkin’s disease, internal malignancy, polycythemia, gout, uremia or pregnancy. Sometimes, even mental stress can be associated with onset.
Chronic prurigo either present as Prurigo Chronica Multiformis or Prurigo Nodularis.
- Prurigo chronica multiformis occurs most frequently in the trunk and legs of the elderly. Excoriation of these pruritic lesions create solid or exudative papules that aggregate to form plaques or lichenoid lesions.
- Prurigo nodularis most commonly affects adolescents and older women. Papules and nodules occur in the extremities, accompanied by intense itching. When rubbed they develop erosion and bloody crusts, resulting in dark brown solid papules or nodules. These are different from Prurigo Chronica Multiformis in that they are isolated and do not aggregate to form plaques.
Apart from sub acute prurigo, where treatment of the primary disease is crucial, this disease is usually managed with steroid and antihistamines, and sometimes even with immune-suppressants. The mainstay of treatment at our clinic is the management of inflammation with acupuncture treatment and herbal therapy.