Pruritus Flashcards
Classes of pruritus
Pruritoceptice
Neurogenic
Mechanism of itching in systemic pruritus
Central nervous system transmission
• Opoid receptors, ILs and neuropeptides imbalance
Mechanism of itching in pruritoceptice itch
Transmitted by unmyelinated group C nerve fibers
(nerve roots in the epidermis, dedicated to itch
and separate from pain conducting group C nerve
fibers)
Treatment of serotonin mediated pruritus
• SSRI & 5HT receptor antagonist (zofran
Opioid receptors
Where is substance P produced in pruritus
In C fibers
Pt. Comes w. chronic, intermittent pruritus of the arm superior
(more often than inferior) to the elbow
Diagnosis?
Brachioradial pruritus
Pt. Comes with interscapular erythema, well-circumscribed
hyperpigmented patch
• The erythema seen here
is due to rubbing and
scratching.
Notalgia paresthetica
Treatment of pruritus in chronic kidney disease
Naltrexone
Treatment of pruritus in primary Billiary cirrhosis
Naltrexone, cholestyramine
Treatment of pruritus in polycythemia vera
Aspirin, PUVA, nb-UVB,
Paroxetine
Causative organism in scabies
Sarcoptes scabiei
Mode of transmission of scabies
Direct contact in crowded areas
The entire 30-day life cycle of
mites of scabies is completed within
The epidermis
Pathognomonic lesion in scabies
The burrow, and furrow
Crusted scabies (Norwegian scabies) are more in people with which disease
HIV
