1. People suspected of urticaria caused by rheumatism can check erythrocyte sedimentation rate, antinuclear antibody, serum complement determination and skin biopsy, which is helpful for the diagnosis of urticaria caused by complement activation.
2. For cold urticaria, syphilis serum test, cryoglobulin, cold fibrinogen, cold hemolysin, ice test and antinuclear antibody test should be checked.
3. The porphyrin in feces and urine should be checked for solar urticaria, and it should be distinguished from systemic lupus erythematosus.
4. Suspected to be related to infection or have a history of hepatitis during physical examination, blood routine examination, hepatitis B antigen and antibody examination, stool eggs, fungi, X-ray examination of diseased parts, etc.
5. If you suspect thyroid disease, you should check the anti-microsomal thyroid antibody.
6. If you suspect that you are allergic to inhalation or ingestion, you should check for allergens. If it is positive, it can be used for desensitization treatment.