The diagnosis of certain patterns of psoriasis should only be made if there is good evidence for the diagnosis. Infections and other conditions may cause pseudo-psoriasis.
Pattern of Psoriasis |
Requirement to Make the Diagnosis of Psoriasis |
scalp |
classic changes (lesions must be palpable; mild cases should show uninvolved skin separating scaly patches) |
toe or nail |
(other skin manifestation of psoriasis) OR ((classic changes) AND (exclusion of Candida, dermatophytes or other condition affecting the nail)) |
localized pustular lesions with palmar-plantar distribution |
presence of other skin manifestations of psoriasis (unequivocal nail changes, plaque psoriasis, etc) |
flexural |
(presence of typical lesions elsewhere) OR ((classic appearance with sharply-defined margins) AND (exclusion of Candida and dermatophytes)) |
If the patient has eczema or a seborrheic dermatitis, then the diagnosis of any form of psoriasis requires classical findings (plaques, nail changes, etc).
Purpose: To make sure that lesions that could be a localized form of psoriasis meet the diagnostic criteria of Baker.
Specialty: Dermatology, Immunology/Rheumatology
Objective: clinical diagnosis, including family history for genetics
ICD-10: L40,