This document discusses different types of psoriasis, including plaque, guttate, inverse, and erythrodermic psoriasis. It describes the clinical features and presentations of each type. Plaque psoriasis is the most common type, appearing as thick red patches covered with silvery scales on the elbows, knees, scalp and lower back. Guttate psoriasis causes small drop-like lesions after a streptococcal infection. Inverse psoriasis affects skin folds. Erythrodermic psoriasis rarely causes the entire body surface to become inflamed and scale. The document also reviews diagnosis, treatment options including topical steroids and phototherapy, and references

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