Psoriasis

1. Dr.Alaa Mohammad AbuZaineh
Teaching Assistant
RAKCOMS
RAKMHSU

5. Psoriasis
A T-cell-mediated inflammatory disease characterized by erythematous
plaques with silvery scales
due to dermal inflammation
and epidermal hyperplasia.

8. Plaque Psoriasis
• the most common form of psoriasis.
• It’s characterized by thick red patches of
skin, often with a silver or white scaly
layer.
• These patches often appear on the:
• elbows
• knees
• lower back
• scalp
• Patches are usually 1 to 10 centimeters
wide, but can also be larger and cover
more of the body.

9. Guttate Psoriasis
• the second most common type
• typical lesions are the size of water drops, 2–
5 mm in diameter.
• They often appear on the torso and limbs, but
they can also appear on your face and scalp.
• Lesions typically occur as an abrupt eruption
after acute infection, such as a streptococcal
pharyngitis.
• This type of psoriasis usually responds rapidly
to broad-band ultraviolet B (UVB)

10. Inverse Psoriasis
(skin folds psoriasis)
• involves folds, recesses,
and flexor surfaces, such
as the ears, axillae, groin,
inframammary folds
,intergluteal crease ,web
spaces.

11. Erythrodermic psoriasis
(exfoliative psoriasis)
• rare
• caused by exacerbation of a pre-existing psoriasis.
• Clinical Presentation :
• looks like severe burns.
• Patients present with extensive erythema and scaling Ultimately, the entire body surface
is dull scarlet and covered by small scales that exfoliate profusely.
• Severe itching
• symptoms of general toxicity, including fever and chills.
• Transepidermal water loss is high
• Secondary infections by Staphylococcus aureus and streptococcal infections
• Severe complications include sepsis, high-output cardiac failure, acute respiratory
distress syndrome, and capillary leak syndrome.
• The mortality rate attributable to the erythroderma approaches 7% in some series

13. Clinical Features/Presentation
• Nails are frequently affected with pitting,
“oil spots,” and onycholysis (lifting of the
nail plate)
• Lesions initially appear small but may
become confluent and can be provoked by
local irritation or trauma (Koebner
phenomenon).
• Some medications such as β-blockers,
lithium, ACEIs, can worsen psoriatic lesions.
• Up to 30% develop psoriatic arthritis
(affecting small joints of hands and feet).

14. Diagnosis & Treatment
• Dx
• Clinical. “Classical” presentation:
• Auspitz sign (pinpoint bleeding when scale is scraped).
• Biopsy if diagnosis is uncertain.
• Tx
• Local disease:
• Topical steroids, calcipotriene (vitamin D derivative) and tazarotene (vitamin A
derivative).
• Mod-Severe disease ( >5% of total body SA)
• UV Phototherapy and Systemic Tx (methotrexate, TNF inhibitors)
• Systemic glucocorticoid are not used as it can precipitate severe
erythrodermic or pustular psoriasis

16. References
• William James, Dirk Elston, James Treat, Misha Rosenbach, Isaac
Neuhaus - Andrews’ Diseases of the Skin_ Clinical Dermatology-
Elsevier (2019)
• 100 Cases in Dermatology - Powell, Ann-Marie, Benton, Emma,
Morris-Jones, Rachael