By:Dr Neda adibi

Researcher and dermatologist in IUMS

The pruritus is an unpleasant sensation which may lead to scratch

The most common complaint in dermatology

With or without skin lesion Can be a manifestation of systemic

disease(10-50%)

Systemic etiology like: Metabolic disorder,hematologic

disease,malignancy ,HIV,complication of pharmacologic agents,neuropsychiatry disease

1. Psoriasis <85%2. ESRD 60-80%3. CTCL 70-80%4. Hodgkin 10-30%5. Pregnanacy 20%6. Herpes zooster 60%

Localized or generalized lesion is not predictive or systemic disease

Acute onset ,without skin lesion less likely to be systemic

Butterfly sign:sparing of the upper mid back may rule out skin problems (it may be psychogenic or systemic)

Most non dermatologic pruritic patients show only excoriation but not primary lesion

Urticaria and mastocytosis have rubbing and pressing not scratching

Involvement of several family members may be due to scabies

Exacerbation after bath may be due to polycytemia or aquagenic pruritus

Nocturnal generalized pruritus,chill and fever may detect hodgkin (pruritus may be up to 5 year before lymphoma)

Most pruritus interferes with sleep except psychogenic

Carefull examination of nail,scalp,hair and lymph node ,liver and spleen

No geneneral need for LAB Generalized pruritus of unknown

etiology ESR,CBCdiff ,LFT,FBS,TFT,fe and ferritin Stool for parasite CXR

Scabies:local or general with a burning component,starts 3-6 week after first infestation

Pediculosis Atopic disease :attacks-

heat,perspiration,wool,stress,contact with air may provoke

Summer type and winter type

Patients with psoriasis y for rarely respond to antihistamines

Prurigo nodularis:more in middle aged women

Atopy,psychological stress , may be underlying

Most effective treatment is thalidomide 200 mg/d for at least 6 months

• It is independent of water temperature or its salinity

• It starts 30 minute following water contact and lasts for 2 hours

• Begin in lower extremity and then generalized with sparing of head ,palm,sole and mucosa

• Treatment cimetidine,colestiramin cyproheptadin,PUVA,UVB,topical capcaiecin two times per week for 4 week

Folliculitis and impetigo may cause pruritus

HSV,varicella,HIV and viral exanthems

DM,hepatic dysfunction,renal dysfunction and tyroid problem

Polypharmacy Lice and scabies Most common cause is xerosis

Decrease the frequency of cold and hot bath and alkaline soap

Decrease the frequency of bath Moisturizers Post CVA using amitriptelyne and

carbamazepin

1-5 % of people more in men 25-90 % are primary Cause:dietary like excessive coffee

intake,poor heigiene,psychogenic Rule out of anxiety and

depression,patch test,colonoscopy in refractive cases

pinworm in children

Treat with cool compress,sitz bath,fragrance free soap,mild corticosteroid cream

Topical capcaiecin

Acute:infection and ACD and ICD Chronic:dermatosis like

psoriasis ,LSA,malignancy

Scalp folliculitis seborhoeic dermatitis,psoriasis and folliculitis

Wound healing may cause pruritus Post burn pruritus Renal failure:gabapentine ,ranal

transplant Hepatic diseas

Myelodysplasia Iron defficiency Polycythemia Lymphoma and lukemia

Thyroid disease Diabetes:genital and perianal pruritus is

common in women with uncontrolled diabetes

HIV

Drug related:estrogen,captopril,co amoxiclav,phenytoin,beta blockers,retinoid.,lithium

Topical like corticosteroid,menthol,coal tar and anasthetics ,urea.

Topical doxepin Capcaiecin Tacrolimus and pimecrolimus PUVA and UVB