Differential diagnosis of psoriasis

According to the clinical manifestations of disease, in particular the characteristics of the skin lesions and pathological features, the general diagnosis is not difficult. But with the following disease. 1. Seborrheic Dermatitis little damage to the edge, basal less invasive, skin rash on the subtype was pityrosporum form Ausspitz's no sign, scalp, seborrheic dermatitis were accompanied alopecia, the hair was not bundles. 2. Pityriasis rosea damage occurred mainly in the proximal extremities and trunk, with the long axis rashes consistent striae. Subtype small and thin. Short duration, the more difficult after recurrence. 3. Lichen Planus damage occurred in the limbs, purple flat polygonal papules, surface wax-like luster. Visibility Wickham profile. Oral often damage, often in varying degrees itching, with specific pathology. 4. Pityriasis red hair damage occurred in the lateral limbs stretch early as keratosis papules, Late in the skin patch around to see keratosis papules. Especially the first phalanx keratosis of the disease papules features. Cover damage to the small subtype, not exfoliation. Accompanied palmoplantar keratoderma excessive. 5. Under cover damage psoriasis small subtype, no sexual multi-subtype, no film, no Auspitz's sign, have no symptoms.