I. Inflammatory and highly proliferative diseases 1. pruritus and pruritic rash: manifested as nodular itchy rash, atopic dermatitis, etc. 2. eosinophilic folliculitis, seborrheic dermatitis, 3. Reiter’s disease: overflowing pustular cutaneous keratosis, often located in the plantar aspect of the feet; cyclic glans, superficial erosion of the glans, fused with each other.
4, adverse drug reactions: see mostly measles-like rash, mostly appearing around 7-10 days after the use of new drugs.
5, drug-induced fat metabolism disorder: HIV protease inhibitor-induced subcutaneous fat loss, commonly on the face.
6, photosensitivity reactions, vasculitis, pigmentation changes, hair and nail lesions.
Second, infectious diseases 1, viral infections: herpes simplex, herpes zoster, genital warts, infectious molluscum contagiosum, oral hairy white spots, etc.
2, fungal infections: candidiasis, cryptococcosis, etc.
3, bacterial infections: folliculitis, impetigo, cellulitis, etc.
3, parasitic diseases 1, helminthiasis: manifested as intensely itchy folliculitis.
2.Scabies: diffuse distribution of rash and itching, i.e. crusted scabies.
Tumor 1.Kaposi’s sarcoma.
2.Lymphoma.
3.Squamous carcinoma and basal cell carcinoma.