Pruritus – colloquially called itching – (synonym: skin itching; ICD-10 L29.9: pruritus, unspecified) is a skin insensitivity that compels scratching.A classification of pruritus is made:
According to localization
- Localized pruritus: itching in one part of the body, for example, the anus (pruritus ani), vulva (vaginal itching; pruritus vulvae).
- Generalized pruritus: itching all over the body.
According to the skin findings
- Pruritus sine materia – itching without visible skin lesions, which may indicate an endogenous disease (internal, neurological or psychiatric diseases) (in about 50% of cases without detectable triggering factors, idiopathic pruritus).
- Pruritus cum materia – itching with visible skin changes; accompanying dermatoses (skin diseases) such as atopic eczema (neurodermatitis) or urticaria (hives).
- Pruritus in chronic scratch lesions – itching on the ground of dermatological or non-dermatological diseases.
According to the course
- Acute pruritus versus chronic pruritus (CP; > 6 weeks).
- Dependent on time of day
- Depending on the season
Pruritus can be a symptom of many diseases (see under “Differential diagnoses”).
At the first occurrence of chronic pruritus, men are older than women.
The prevalence of chronic pruritus is 12.3% in people under 30 years of age and rises to 20.3% in people aged 60 to 70 (in Germany). Children also frequently suffer from pruritus.
The incidence (frequency of new cases) of chronic pruritus is 7%.
Course and prognosis: Therapy is cause-related. Pruritus often occurs in dermatoses (skin diseases), xeroderma (dry skin) or aging skin, but can also occur in diseases of the internal organs (e.g. liver, kidneys). If no cause is identifiable, therapy becomes difficult. Chronic pruritus may even persist despite treatment of the cause.
Comorbidities (concomitant diseases): Patients with pruritus are almost six times as likely to develop a malignancy (tumor disease) as patients without this symptom. In 36% of cases of malignancy, exanthema (skin rash) was also present. For details on pruritus and malignancy, see “.causes/neoplasms.”
