What are the symptoms of allergic urticaria?

Allergic urticaria is an infectious disease, which is usually caused by contact with infectious sources. Suffering from allergic urticaria can easily lead to symptoms of loss of appetite, fatigue, frequent colds, poor body resistance, etc. Papules, redness and swelling are prone to appear on the surface of human skin, which can easily spread throughout the body and usually require medication for treatment.

Allergic rash

1. Acquired rubella

(1) The incubation period is 14 to 21 days.

(2) The prodromal period is 1 to 2 days, characterized by low or moderate fever, headache, loss of appetite, fatigue, weakness, and mild upper respiratory tract symptoms such as cough, sneezing, runny nose, sore throat, and conjunctival congestion. Occasionally, there may be vomiting, diarrhea, nosebleeds, and swollen gums. Some patients may have rose-colored or hemorrhagic macules on the pharynx and soft palate, but there is no roughness, congestion, or mucosal spots on the buccal mucosa.

(3) The rash usually appears 1 to 2 days after the fever. The rash first appears on the face and neck, and quickly spreads to the trunk and limbs, covering the entire body within 1 day, but there is usually no rash on the palms and soles of the feet. The rash initially appears as fine, light red macules, maculopapules or papules, 2 to 3 mm in diameter. The rash on the face and distal limbs is sparse, and some are fused, similar to measles. The rash is dense and fused into patches on the trunk, especially the back, which is similar to scarlet fever. The rash on the trunk usually lasts for 3 days (1 to 4 days) and then disappears, and is also called "three-day measles." There may be swollen lymph nodes behind the ears, behind the head, and in the neck, conjunctivitis, or joint pain (arthritis).

(4) Rubella without rash Rubella patients only have fever, upper respiratory tract inflammation, swollen and painful lymph nodes but no rash; they may also not have any symptoms or signs after being infected with the rubella virus, and the rubella antibody test is positive in serological examination, which is the so-called latent infection or subclinical patient. The ratio of patients with overt infection to those without rash or with latent infection is 1:6 to 1:9.

2. Congenital rubella syndrome

Maternal infection with RV in the first three months of pregnancy can cause multi-system birth defects in the fetus, namely GRS. The earlier the infection occurs, the more serious the damage to the fetus. After the fetus is infected, severe cases may lead to stillbirth, miscarriage, or premature birth; mild cases may lead to fetal developmental retardation and even affect all systems of the body, resulting in multiple malformations. Congenital malformations in newborns are mostly caused by congenital rubella. Most congenital patients have clinical symptoms at birth, but symptoms and new malformations may not appear until several months to years after birth.

examine

1. Laboratory examination

(1) Peripheral blood shows a decrease in the total white blood cell count, an increase in the number of lymphocytes, and the presence of atypical lymphocytes and plasma cells.

(2) Virus isolation: Nasopharyngeal secretions from rubella patients, and urine, cerebrospinal fluid, blood, bone marrow, etc. from congenital rubella patients are cultured in RK-13, African green monkey kidney aneuploid cell line, or normal rabbit corneal aneuploid cell line (SIRC cells) and other cell lines to isolate rubella virus, which is then identified by immunofluorescence.

(3) Serum antibody tests such as hemagglutination inhibition test, neutralization test, complement fixation test and immunofluorescence assay are considered positive if the antibody titer of two samples of serum increases by more than 4 times. The hemagglutination inhibition test is the most applicable and has the advantages of being rapid, simple and reliable. This antibody appears when the rash appears, rises rapidly in 1 to 2 weeks, drops to the initial level after 4 to 12 months, and can be maintained for life. It is used to detect rubella-specific antibodies IgM and IgG. Local secretory IgA antibodies can be detected in nasopharyngeal secretions and can aid in diagnosis. Rubella virus RNA can also be detected by dot blot hybridization. Rubella retinitis is often an important sign for the diagnosis of congenital rubella. Brown or dark brown pigment spots of varying sizes, in the form of dots or stripes, often appear on the retina. In severe cases, the spots are large and accompanied by yellow lenses. The retinal blood vessels are often narrower than normal.

2. Auxiliary examination

Patients with concurrent myocarditis have changes in electrocardiogram and cardiac enzyme spectrum.