Urticaria, often referred to as “rubella”, is a common allergy-induced skin disease, with skin manifestations in mild cases, and shock and respiratory distress in severe cases, which can be life-threatening if not treated promptly. The following is a detailed discussion of the causes, clinical manifestations, prevention and treatment of urticaria, with case studies. Zuo Fuguo, Department of Dermatology and Venereology, Shanghai Oriental Hospital
I. Causes of formation
For acute urticaria, there are mostly triggering factors, while for chronic urticaria, most patients cannot find the exact cause.
Food is the most common cause, including animal proteins such as fish, shrimp and crab, beef and mutton, milk and eggs, as well as plant-based ones such as strawberries, onions, ginger, garlic and tomatoes; some food additives can also cause urticaria. Secondly, drugs can also cause urticaria, the most common drugs such as penicillin, cephalosporin antibiotics, serum preparations such as tetanus and antipyretic analgesics. Infectious factors also tend to cause this disease such as viral, bacterial, fungal and parasitic infections. Various physical factors such as sunlight, cold, heat, friction and pressure. Various inhalants such as animal fur, pollen, etc. are also likely to cause urticaria. Systemic diseases such as autoimmune diseases such as lupus erythematosus, malignant tumors, and metabolic disorders are also causes of chronic urticaria. Other diseases such as mental stress, endocrine abnormalities, etc.
Clinical manifestations
The disease can occur at any age, according to the course of the disease can be divided into acute and chronic urticaria, regardless of the acute and chronic, the appearance of wind masses on the skin is its basic damage.
For acute urticaria, the onset of the disease is more acute, and the patient feels itchy skin at the beginning, and soon there are wind clusters (commonly known as rubella bumps) on the itchy area. The rash usually lasts no more than 24 hours, and untreated urticaria usually has an orange peel-like appearance and can be red or pale white in color. Some patients may have nausea, vomiting, headache, head swelling, abdominal pain, diarrhea, and in severe cases, systemic symptoms such as chest tightness, discomfort, pallor, accelerated heart rate, weak pulse, decreased blood pressure, and shortness of breath. Acute urticaria is often cured within a short period of time after timely treatment, so it is called acute urticaria.
If there are repeated attacks of urticaria for more than 6 weeks, it is called chronic urticaria, which is sometimes more or less frequent and recurrent for months or years, but there are occasional acute attacks.
In addition to acute and chronic urticaria, there are also the following special types of urticaria, mainly including the following:
1. Skin scratching sign/artificial urticaria
This is a weak mechanical stimulus such as scratching or rubbing of clothing that can produce a wind cluster on the skin, often in the direction of scratching, accompanied by itching.
2.Pressure urticaria
It may be accompanied by fever, headache, arthralgia, general discomfort and mildly increased white blood cell count. Localized widespread swelling resembles angioedema and is likely to occur in the hands, feet and buttocks.
3.Cholinergic urticaria
The patient feels tingling and itching of the skin all over the body. Mostly occurs during or after exercise, heat, emotional stress, eating irritating food, accompanied by itching, stinging, burning.
4.Cold urticaria
Can be divided into familial and acquired two, the former is more rare. Acquired is more common, patients often occur when the temperature drops or after contact with cold water, within a few minutes of local itchy edema and wind masses, mostly on the face, hands, serious other parts can also be involved. Headache, skin flushing, hypotension, and even shock can occur.
5.Solar urticaria
After the skin is exposed to sunlight for a few minutes, local itching, erythema, and wind masses appear rapidly. The rash may be accompanied by chills, fatigue, fainting, and intestinal cramps.
6.Contact urticaria
It is characterized by skin contact with certain allergens after the occurrence of wind and erythema.
7, Others include heat urticaria, motor urticaria, tremor urticaria, water urticaria, adrenergic urticaria, current urticaria and other more rare types of urticaria.
III. Diagnosis
It is easy to diagnose urticaria, and the diagnosis can be confirmed based on the clinical appearance of wind clusters with itching, but it is often difficult to determine the cause of urticaria, especially chronic urticaria should be as clear as possible the cause of urticaria, which is also the key to treating recurrent chronic urticaria.
IV. Treatment
1.General treatment
Each patient should try to find the cause of the attack and avoid it. For the infection caused, the primary infection should be actively treated. If the allergy is caused by medication, stop using the allergy medication. If you are allergic to food, do not eat the food again. If the cause is not clear, you can do allergen test.
2.Medication
(1) antihistamines mainly H receptor antagonists, with strong antihistamine and anti-inflammatory mediator effect, is the first-line drugs for the treatment of various types of urticaria. H1 receptor antagonists commonly used are the first generation (cycloheximide, paracetamol), the second generation (cetirizine, imipramine, loratadine, epalrestine), etc. H1 receptor antagonists, especially the first generation have more drowsiness, resulting in poor urination and other adverse effects, the application should take into account the patient’s occupation, such as high-altitude work, drivers, etc. and whether the elderly patients have prostate hypertrophy; when individual treatment is ineffective, the The H1 receptor antagonist can be used in combination with two different types of H1 receptor antagonists. Commonly used H2 receptor antagonists are cimetidine, ranitidine, famotidine, etc., rarely used alone to treat urticaria, often combined with H1 receptor antagonists to play a better therapeutic role.
(2) Doxepin belongs to the tricyclic antidepressants. For patients with urticaria in which antihistamines are ineffective, doxepin is a better choice of drugs, especially for chronic urticaria, and the adverse effects are small.
(3) Drugs that inhibit the degranulation of mast cells and reduce the release of histamine, commonly used include ketotilol, sodium cromoglycate, trinostat, montelukast, etc.
(4) Glucocorticoids are only used as second-line drugs for the treatment of urticaria, and are generally used for severe acute urticaria with systemic symptoms such as gastrointestinal symptoms, hypotension, dyspnea, chest tightness, etc. The aim is to provide early relief of symptoms and avoid further progression of the disease. Commonly used drugs are prednisone or prednisolone, dexamethasone, betamethasone, etc.
(5) Immunosuppressants Immunosuppressants can be used only when satisfactory results cannot be achieved with the above treatments, including: cyclosporine, rhodopsin, azathioprine, cyclophosphamide, methotrexate and immunoglobulin. Due to the adverse effects of immunosuppressants, they are generally not recommended for the treatment of urticaria.
(6) Other drugs such as drugs that reduce vascular permeability such as vitamin C, vitamin P, calcium, etc., are often used in combination with antihistamines.
3, ultraviolet light therapy for chronic urticaria may be a good choice, we apply narrow-wave ultraviolet light treatment of chronic idiopathic urticaria, achieved relatively good results.
Case analysis
Case summary: The patient, Mr. Wang, 36 years old, worked as a foreigner and was engaged in the courier industry. He visited the clinic with “itchiness all over the body for 3 days”; 3 days ago, after a colleague’s dinner and drinking, his face started to get red urticaria, accompanied by intense itching and scratching, and the rash soon spread to the whole body, accompanied by abdominal pain and a slight feeling of chest tightness, he bought a box of “loratadine” from a pharmacy on his own. After using it according to the instruction, the rash improved slightly, but he still had chest tightness, so he came to Oriental Hospital Dermatology Department. The patient had no fever, headache or other symptoms since the onset of the disease. He was in good health, denied history of allergy, denied family history of hereditary disease or similar diseases. Dermatologic examination: generalized erythema and wind masses on the trunk and extremities, localized fusion into patches, and linear scratch marks on the trunk and extremities.
Case analysis: Mr. Zhang is a young male, occurred after attending a colleague’s wedding banquet, red wind masses all over the body accompanied by chest tightness, the first thing to consider is that Mr. Zhang has an allergic skin disease, dermatology clinical diagnosis of acute urticaria. He also had symptoms of abdominal pain, in addition to acute urticaria can be accompanied by gastrointestinal symptoms, because Mr. Zhang has a history of drinking alcohol at wedding banquets, at this time to exclude acute abdominal diseases such as gastroenteritis, pancreatitis, etc.; at the same time also consciously have chest tightness, to exclude coronary heart disease. We had a consultation with emergency surgery and cardiovascular medicine respectively, and ruled out acute abdomen and coronary heart disease. Therefore, Mr. Zhang’s accompanying abdominal pain and chest tightness were the concomitant symptoms of a severe case of acute urticaria. Mr. Zhang was prescribed the following: 1) Dexamethasone 5mg, once intramuscularly; paracetamol 10mg, once intramuscularly; loratadine tablets 10mg, orally, once a day; and glyburide lotion, topically, three times a day. 2) He was kept in the observation room to observe changes in his condition. 3) Mr. Zhang was instructed to take rest and eat a lighter diet. After treatment, the symptoms of chest tightness and abdominal pain gradually subsided and disappeared, and he left the hospital the next day.
Oriental Hospital Department of Skin and Venereal Diseases
The Department of Dermatology and Venereal Diseases is a clinical specialty department integrating medical treatment, teaching and scientific research. It undertakes the teaching of dermatology and venereal diseases of the three clinical departments of Tongji University School of Medicine and the prevention and treatment of dermatology and venereal diseases in Pudong New Area. There are 10 doctors in the department, including 2 deputy chief physicians, 5 attending physicians and 3 residents, including 2 doctors with doctoral degrees and 3 doctors with master’s degrees. The whole department has a dermatology clinic, venereal disease clinic and treatment room, with an annual outpatient volume of more than 100,000 visits. We carry out various treatments and programs such as electrodermabrasion, laser, ultraviolet phototherapy, microwave, cold spray, photodynamic, allergen testing and dermatologic surgery all year round. We take respect and care for patients as our foothold and provide scientific, formal and reasonable treatment with good service attitude.
About the author of this article.
Fuguo Zuo, Male, Associate Chief Physician, MD, graduated from the Department of Dermatology, Huashan Hospital, Fudan University. He is now a member of the Dermatology and Venereology Branch of the Shanghai Chinese Medical Association and a member of the Professional Committee of Dermatopharmacology of the Shanghai Pharmacological Society. He has been engaged in clinical, scientific research and teaching work in dermatology and venereology for more than ten years and has rich clinical experience in the prevention and treatment of skin diseases and venereal diseases. She specializes in the treatment of allergic skin diseases such as chronic urticaria, pigmentary diseases such as vitiligo and melasma, psoriasis, alopecia, acne, eczema and dermatitis, as well as dermatologic surgery and medical aesthetic lasers.
Specialist Clinic Hours: Every Monday and Wednesday morning (Oriental Hospital South Campus)