erythema behind the ear
Introduction
Introduction The erythema behind the ear is one of the clinical manifestations of infectious erythema. The disease is a mild febrile infectious disease caused by parvovirus infection, which is more common in children under 12 years of age. Prevailing in spring. A vesicular pustular rash occurs, leading to anemia, aplastic crisis and chronic myelogenous failure, which may be caused by the invasion of the myeloid progenitor cells by the virus. The disease needs to be associated with rubella, measles, and skin and blood vessel damage diseases such as vascular purpura, infectious erythema, scarlet fever, rubella, measles and the like.
Cause
Cause
Infectious diseases caused by viruses, the pathogen is parvovirus B19, active placenta transmission can occur when the virus is first infected. The B19 virus is also considered to be the primary cause of chronic anemia. For a long time, the disease was considered to be a viral infection, but it failed to obtain laboratory evidence. It was not until 1983 that Andersorl and others detected the IgM and IgG antibodies of parvovirus (parvirus B19; PVB19) from the serum of 33 patients with infectious erythema. Therefore, this virus is considered to be the cause of infectious erythema. Later, Plummer et al. also detected PVDNA in the rash of patients with infectious erythema, and they also found that some family members and their school contacts did not show symptoms, but they all had anti-PV IgM and IgG antibodies. . The authors believe that PVB19 can cause many clinical manifestations, including no clinical symptoms to typical rashes. Some studies have found that pregnant women infected with PVB19 can cause miscarriage, stillbirth and fetal edema.
Examine
an examination
Related inspection
Ear, nose, throat swab bacterial culture Otolaryngology CT examination
In the acute phase, virions can be seen by electron microscopy, and specific IgM antibodies in serum can be detected in the acute phase or early recovery. Specific viral DNA can be detected in serum and throat secretions.
1. Blood examination: Peripheral blood leukocytes can be mildly reduced or normal, and hemoglobin and platelets can be reduced in people with aplastic anemia.
2.B19: DNA test PCR method can detect DNA from patient serum, CSF and diseased tissue, which is a means of diagnosis.
3. Immunological examination: B19 antigen can be detected by radioimmunoassay or ELISA, and more IgM antibodies for B19 can be detected. The disease can reach a peak at 1 week, and it will decrease after 2 months. The diagnostic value of the current infection. IgG antibodies appear later, last a long time, and have a protective effect.
4. Pathological changes: epidermal cell edema, dermal papillary vasodilation, endothelial cell swelling, tissue cell infiltration around blood vessels, hair follicles and sweat glands, but chronic inflammation changes, no diagnostic value.
Diagnosis
Differential diagnosis
1. Need to be differentiated from rubella and measles.
2. Need to be differentiated from skin and vascular damage.
(1) vascular purpura: patients have children, but also adults. First, fever, sore throat, salivation, etc. appeared. After 48 hours, a rash appeared, which was characterized by vascular purpura. First appeared in the limbs, and extended to the trunk, neck and even the face. Purpura persists for several days and can be accompanied by short-term leukopenia and thrombocytopenia. Some patients have abdominal pain or severe joint pain. Histological examination showed necrotizing vasculitis and non-necrotic vasculitis.
(2) Infectious erythema (erythema infectiosum): This disease is also known as the fifth disease. Tschamer has described the disease in detail in 1889. It has been popular many times around the world, and it was not until 1981 that HPV-B19 was identified as its pathogen.
The clinical manifestations of infectious erythema in children are preceded by fever, general malaise, sore throat, and nasal discharge. After 2 to 3 days, a rash appears, mostly starting from the face, and soon merges into a piece with mild edema, forming a special performance of "slap face". The rash quickly spreads to the trunk and limbs. First, it is a maculopapular rash, and the middle part is first faded to form a mesh or lace. The rash can be aggravated by sun exposure, exercise, and bathing, accompanied by itching. After 2 to 4 days, the rash subsides, and the pigmentation can be resolved in a few days. The whole course is 5 to 9 days.
There are also a few cases of HPV-B19 in adults with infectious erythema, but there are few "slap faces" and fewer rashes. But within a few days to weeks after the illness, 80% of people have joint pain.
(3) Scarlet fever: The disease is acutely ill, clinical manifestations of sore throat, high fever, rash is diffuse erythema, pale circles around the mouth, grass plum tongue and post-peeling signs. Pascal's sign: positive.
(4) Rubella: upper respiratory tract catarrhal symptoms are more obvious, fever, measles-like rash, swollen lymph nodes behind the ear and after the pillow.
(5) Measles: high fever, upper respiratory tract catarrh, obvious rash, maculopapular rash, normal skin between rashes. The early buccal mucosa is visible in the Koplik plaque.
