Diagnosis And Treatment Of Urticaria

First, the diagnosis and differential diagnosis of urticaria
1. Medical history and physical examination
Detailed medical history and comprehensive physical examination should be collected, including possible predisposing factors and mitigating factors, course of disease, frequency of attack, duration of skin lesions, day and night episodes, size and number of wheals, shape and distribution of wheal, and angioedema. Itching or pain level, whether there is pigmentation after regression, history of allergies in individuals or families, history of infection, history of visceral disease, history of trauma, history of surgery, history of medication, psychological and mental status, menstrual history, lifestyle habits, work and Living environment and past treatment response.
2. Laboratory examination
Usually urticaria does not require more tests. Acute patients can check blood routines to see if the disease is associated with infection or allergies. Chronic patients may be considered for related tests such as blood routine, fecal eggs, liver and kidney function, immunoglobulin, erythrocyte sedimentation rate, if the condition is severe, the course of disease is long, or the response to conventional doses of antihistamines is poor. C-reactive protein, complement and various autoantibodies, and the like. Allergen screening, food diary, autologous serum skin test (ASST) and Helicobacter pylori infection may be performed as necessary to rule out and determine the role of relevant factors in the pathogenesis. The role of lgE-mediated food allergens in the pathogenesis of urticaria is limited, and the results of allergen tests should be correctly analyzed. Conditional units may conduct double-blind, placebo-controlled food challenge tests as appropriate.
3. Classification diagnosis
Combining medical history and physical examination, urticaria is divided into spontaneous and inducing. The former is divided into acute and chronic according to whether the course of disease is ≥6 weeks. The latter is divided into physical and non-physical urticaria according to whether the disease is related to physical factors, and further classified according to the definition in Table 1. There may be two or more types of urticaria present in the same patient, such as chronic spontaneous urticaria combined with artificial urticaria.
4. Differential diagnosis
It is mainly distinguished from urticaria vasculitis. The latter usually has a wheal for more than 24 hours. After the skin lesions are recovered, there is pigmentation. The pathology suggests inflammatory changes. In addition, it is also necessary to identify other diseases such as urticaria type drug eruption, serum-like reaction, papular urticaria, Staphylococcus aureus infection, adult Still disease, hereditary angioedema, etc., which are formed by wheal or angioedema.
Second, the treatment of urticaria
First-line treatment
Second-generation non-sedating or low-sedation antihistamines are preferred, and the dose is gradually reduced after treatment is effective to achieve effective control of whealing. In order to improve the quality of life of patients, the course of chronic urticaria is generally not less than 1 month, and may be extended to 3 to 6 months or longer if necessary. The first-generation antihistamines are effective in the treatment of urticaria, but their clinical application is limited by adverse reactions such as central sedation and anticholinergic effects. Under the premise of cautions on contraindications, adverse reactions and drug interactions, you may choose as appropriate.
Commonly used anti-histamines include chlorpheniramine, diphenhydramine, doxepin, promethazine, ketotifen, etc. Second-generation antihistamines include cetirizine, levocetirizine, and chlorine. Ritadine, desloratadine, fexofenadine, avastin, ebastine, eplestin, mizolastine, olopatadine, and the like.
2. Second line treatment
The conventional dose can not effectively control the symptoms after 1 to 2 weeks. Considering the difference in response to different types of individuals or urticaria, you can choose to change the variety or obtain the patient’s informed consent to increase the dose by 2 to 4 times; Antihistamines, which can be taken at bedtime to reduce adverse reactions; combined with second-generation antihistamines, the combination of drugs of similar structure, such as loratadine and desloratadine, to improve anti-inflammatory effects; Combined anti-leukotriene drugs, especially urticaria induced by non-steroidal anti-inflammatory drugs.
3. Third-line treatment
For patients who are ineffective in the above treatment, the following treatments may be considered: cyclosporine, 3 to 5 mg/kg per day, orally 2 to 3 times. Due to its high incidence of adverse reactions, it is only used in patients who are severely ineffective for any dose of antihistamines. Glucocorticoid, suitable for acute, severe or otitis with laryngeal edema, prednisone 30 ~ 40mg (or equivalent dose), after 4 ~ 5d oral withdrawal, does not advocate routine use in chronic urticaria. Immunoglobulins such as intravenous immunoglobulin, 2g daily, for 5d, are suitable for severe autoimmune urticaria. Biologics, such as foreign studies, show that omalizumab (anti-lgE monoclonal antibody) has a positive effect on refractory chronic urticaria. Phototherapy, for patients with chronic idiopathic urticaria and artificial urticaria, can be treated with UVA and UVB for 1 to 3 months while antihistamine treatment.
4. Treatment of acute urticaria
When actively identifying and eliminating the cause and oral anti-resistance drugs can not effectively control the symptoms, you can choose glucocorticoid: prednisone 30 ~ 40mg, after 4 ~ 5d oral withdrawal, or a considerable dose of dexamethasone intravenous or intramuscular Injection, especially for severe or otitis with laryngeal edema; 1:1000 adrenaline solution 0.2 ~ 0.4ml subcutaneous or intramuscular injection, can be used for acute urticaria with shock or severe urticaria with angioedema.
5. Treatment of induced urticaria
Inducible urticaria is relatively inferior to conventional antihistamines, and in the case of ineffective treatment, special treatments should be chosen.
6. Treatment of pregnant and lactating women and children
In principle, antihistamines should be avoided during pregnancy. However, if symptoms recurs repeatedly, seriously affecting the life and work of patients, when anti-histamine therapy must be used, patients should be informed that there is no absolutely safe and reliable drug, and relatively safe and reliable drugs such as loratadine should be selected in the case of weighing the pros and cons. Wait. Most antihistamines can be secreted into the milk. In comparison, cetirizine and loratadine have lower levels of secretion in milk, and lactating women may recommend these drugs as appropriate and use lower doses whenever possible. Chlorpheniramine can be secreted through the milk, reducing the appetite of the baby and causing drowsiness, etc., should be avoided.
Non-sedating antihistamines are also a first-line option for urticaria treatment. Different drugs have significant differences in their minimum age limits and doses to be used, and should be used in accordance with the specifications of the drug instructions. Similarly, in patients with ineffective treatment, combined with the first generation (evening) and the second generation (daytime use) antihistamines, but pay attention to the sedative antihistamines for children to learn, etc. influences.