Differential diagnosis of psoriasis

Area of Science:

• Dermatology
• Pathology

Background:

• Psoriasis diagnosis relies on characteristic clinical presentations, including erythematous, scaly plaques on extensor surfaces.
• Histopathological findings like parakeratosis, acanthosis, and specific microabscesses confirm active psoriasis lesions.

Purpose of the Study:

• To outline the diagnostic criteria for psoriasis.
• To discuss challenges in diagnosing atypical psoriasis variants and localized forms.
• To explore psoriasiform eruptions linked to diagnostic or therapeutic agents.

Main Methods:

• Review of clinical and histopathological features of psoriasis.
• Analysis of diagnostic challenges in various psoriasis subtypes and locations.
• Discussion of drug-induced psoriasiform eruptions.

Main Results:

• Typical psoriasis presents with distinct plaques and specific histopathological markers (Munro microabscess, spongiform pustule of Kogoj).
• Diagnostic difficulties arise with variants like guttate, follicular, erythrodermic, and pustular psoriasis.
• Psoriatic lesions in specific sites (palms, soles, nails) and drug-induced eruptions require careful evaluation.

Conclusions:

• While classic psoriasis is easily diagnosed, clinical variants and specific localizations necessitate careful assessment.
• Understanding histopathological correlates aids in confirming the diagnosis.
• The potential for drug-induced psoriasiform eruptions in psoriatic patients warrants consideration.