Brachioradial Pruritus NHS | A4 Medicine

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Chronic Pruritus
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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 age Estimated that
60 of people gt 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
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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 foliaceus Pityriasis rosea Fiberglass
dermatitis Fungal infections Mycosis fungoides
Seborrhoeic dermatitis history-Onset , duration
Intensity Timing Itch characteristic for
eg prickling crawling burning Rash ? Site
eg entire skin palpebral conjunctiva perianal /
perogenital ear canals , eyelids, nostrils
Associated symptoms Disturbing sleep ? Relieving
factors Medical history Drug history , cosmetics
, creams ? Blood transfusions Others itching ? (
scabies ) Alcohol abuse , sexual hx , drug abuse
Dietary history Examination Assess severity for
eg using an visual analogue score ( VAS ) Skin
examination Mucous membranes Scalp Hair Nails
Anogenital region Distribution of primary and
secondary skin lesions Skin signs of systemic
disease Palpation of liver , kidneys , spleen
and lymph nodes Mental state psychological
impact
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Testing- Renal function FBC , ESR LFTs , Bone
profile , Vit D , Bl glucose , HbA1c TFTs Iron
studies Blood morphology , LDH ANA HIV and
hepatitis A, B and C serology Electrophoresis
IgE serum levels ( total and sllergen specific )
Stool test for ova , parasites or blood Prick
tests with specific allergens Microscopy of skin
scrapings Dermoscopy Skin biopsy CXR CT scan of
neck , thorax , abdomen and pelvis MRI of brain
and spinal cord Red flags- Bullous pemphigoid
Hodgkins lymphoma Polycythemia vera HIV
Infection / AIDS Paraneoplastic pruritis Brain
tumour Stroke management- Where possible manage
underlying cause Discontinue drugs where
possible Emollients with active ingredients for
eg Menthol 0.5 or 1 , phenol or camphor
Treat skin infections Topical therapy Capsaican
particularly renal ( poor pt compliance ) ,
topical doxepin , crotamion cream Systemic
therapy ( seek adv from dermatology where
appropriate ) ? sedating anti-histamines eg
hydroxyzine ( Atarax ) 10-25 mg nocte ? Non
sedating anti histamines eg Fexofenadine 180 mg
? Anti- depressants eg Tricyclics (
amitriptyline , doxepin ) , SSRIs ( paroxetine )
, Mirtazepine _at_ 15 mg ? Anti-convulsants and
pain modulators eg gabapentin or pregabalin ?
Opioid receptor antagonists agonists eg
Naltrexone ? Rifampicin ( hepatic pruritus ) ,
Cholestyramine ? Ondansetron , NSAIDs , H1 and
H2 antagonists in combination for eg
fexofenadine and cimetidine UV phototherapy
Psychosomatic therapy