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
12.
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
15.
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
Editor's Notes
Recurrent episodes may be related to pharyngeal carriage of the responsible streptococcus by the patient or a close contact. A course of a semisynthetic penicillin (e.g., dicloxacillin, 250 mg four times daily for 10 days) with rifampin (600 mg/day for adults) may be required to clear chronic streptococcal carriage.
Lesions are classically found on the extensor surfaces, including the elbows and knees.
Scalp and lumbosacral regions are often involved.
Biopsy Findings : thickened epidermis, elongated rete ridges, an absent granular cell layer, preservation of nuclei in the stratum corneum (parakeratosis), and a sterile neutrophilic in ltrate in the stratum corneum (Munro microabscess).
Vit D Derivatives (calcipotriene) , topical retinoids , and calcineurin inhibitors (tacrolimus) are also effective and are often chosen for the face and other areas where where GC induced skin thinning would be problematic .
extensive skin involvement
UV light therapy (except in immunosuppressed patients who can develop skin cancer from UV).
