Pediatric Measles
Introduction
Introduction to pediatric measles Pediatric rash is caused by poliovirus infection, mainly a highly contagious disease affecting the skin and respiratory tract. The incubation period for this disease is 7-14 days. The incidence of complications in pediatric measles is high and can be complicated by pneumonia. Pediatric rash is an infectious disease that is prone to occur in late winter and early spring. It is also an acute infectious disease with high incidence and easy infection in childhood. It is caused by the pediatric measles virus. Its symptoms are inflammatory lesions of the upper respiratory tract, mucosal plaques on the oral mucosa, fever, and a typical symptom is rash. In the case of pediatric measles pneumonia, according to the type of bacteria and drug susceptibility test, rational use of antibiotics. basic knowledge The proportion of illness: 0.3% Susceptible people: children Mode of infection: respiratory transmission Complications: pneumonia Myocarditis Pediatric bronchitis
Cause
The cause of pediatric measles
Causes:
Measles virus infection (65%):
Modern medicine believes that measles is caused by measles virus infection. The patient is the only source of infection, which is contagious from 2 to 3 days after the late incubation period to 5 days after the rash (if pneumonia is present, it is delayed to 10 days after the rash). With the widespread use of live attenuated measles vaccines, the incidence has been greatly reduced, but in a few areas due to inadequate prevention work, there is still a partial epidemic. It is mainly transmitted through respiratory droplets, and can also be transmitted indirectly through contaminated daily necessities and clothing.
Low immunity (25%):
Children's immunity characteristics often show that the immune system is not mature enough, and the function is still not perfect. Due to the low immune function, the body is not resistant, and the measles virus takes advantage of it and causes infection.
Prevention
Measles prevention
1. Manage the source of infection
The patients should be closely separated, and the contacts should be quarantined and quarantined for 3 weeks; during the epidemic period, nursery schools, kindergartens and other children's institutions should suspend the pick-up and reception of susceptible children.
2. Cut off the route of transmission
The patient should pay attention to ventilation and ventilation, and make full use of sunlight or ultraviolet radiation. After leaving the hospital, the medical staff should wash their hands to change the outerwear or stay in the air circulation for 20 minutes to reach the susceptible person.
3. Protect susceptible populations
(1) The application of automatic immunization against measles is the most effective way to prevent measles.
(2) Passive immunization The vulnerable, sick, and young susceptible children with close contact history should adopt passive immunization.
Complication
Pediatric measles complications Complications pneumonia myocarditis pediatric bronchitis
In the process of measles infection, due to low immunity in the body, it is easy to secondary to other viral or bacterial infections, especially in young and weak and malnourished patients, but also due to poor environment and improper care. Secondary infection of the respiratory tract is the most common, often caused by Staphylococcus aureus, hemolytic streptococcus, Streptococcus pneumoniae, influenza bacillus or Escherichia coli; secondary viral infection is infected with adenovirus and respiratory syncytial virus, also Bacterial virus co-infection can occur.
Symptom
Pediatric Measles Symptoms Common Symptoms Skin rash rash appetite loss fever flow clear lymph nodes swelling tears scarlet fever hot rash pharyngeal congestion
Because pediatric measles is also a respiratory disease, there are symptoms of a common cold and fever, in addition to its specific symptoms. On the first or second day, the sick child may have fever, runny nose, red eyes and tears, dry cough, and symptoms of diarrhea. On the third day, the body temperature of the sick child decreased, and white salty spots appeared in the oral lining. On the fourth to fifth days, the sick child's temperature rose again and a rash appeared. The rash first appeared on the forehead and behind the ear, showing red spots, about 2-3 mm wide, slightly raised. The rash gradually spreads to the head and body. As the rash spreads, the spots become larger and larger and connect to each other. On the sixth day, the rash began to subside and faded quickly. Usually on the seventh day, all symptoms disappeared. In most cases, the symptoms of the sick child disappeared within 7-10 days.
Typical pediatric measles can be divided into the following four phases
1. Incubation period: The incubation period of pediatric measles is generally 10-14 days, and it is as short as 1 week. There may be a slight increase in body temperature during the incubation period.
2, prodromal period: pediatric measles prodromal period is also called pre- rash, usually 3-4 days. The main performance of this period is similar to the symptoms of upper respiratory tract infection: 1 fever, found in all cases, mostly moderate to fever; 2 cough, runny, tears, pharyngeal congestion and other catarrhal symptoms, prominent eye symptoms, conjunctival inflammation, Eyelid edema, increased tears, photophobia, and an obvious congestion line at the edge of the lower eyelid (Stimson line) is extremely helpful in diagnosing pediatric measles. 3Koplik spots appear 24 to 48 hours before the rash, which is a grayish white dot with a diameter of about 1.0mm. There is a red halo outside. It starts to appear only on the buccal mucosa of the lower molars, but it increases rapidly in one day and can be involved. The entire buccal mucosa spreads to the mucous membrane of the lips. The mucosal rash gradually disappears after the appearance of the rash, leaving dark red dots. 4 Occasionally, the skin is sputum, faint rash or scarlet fever-like rash, disappearing in the presence of a typical rash; 5 cases may have some non-specific symptoms, such as general malaise, loss of appetite, lack of energy and so on. Infants may have digestive symptoms.
3, the rash period: children in the rash period more than 3-4 days after fever, rash. The body temperature can suddenly rise to 40-40.5 ° C, the rash begins to sparse and irregular red maculopapular rash, the skin between the rash is normal, first seen in the back of the ear, neck, along the hairline edge, develops downward within 24 hours, throughout the face, On the trunk and upper limbs, the rash on the third day involved the lower limbs and the feet. In severe cases, the rash often merged, the skin was edematous, and the face was swollen and deformed. Most rashes fade, but there are also those who have problems. There are lymphadenopathy and splenomegaly throughout the body, and for several weeks, mesenteric lymphadenopathy can cause abdominal pain, diarrhea and vomiting. Pathological changes in the genital measles of the appendix mucosa can cause symptoms of appendicitis. In the extreme stage of the disease, especially in the case of high fever, there are often convulsions, irritation and lethargy. Most of them are transient, and disappear after heat retreat, which has nothing to do with future central nervous system complications. In this period, the lungs have wet rales, and X-ray examination shows an increase in lung texture.
4, recovery period: 3-4 days after rash in children began to fade, the order of regression is the same as when the rash occurs; in the absence of comorbidities, appetite, mental and other symptoms have also improved. After the rash retreats, the skin remains with bran-like desquamation and brown pigmentation, which heals in 7-10 days.
Other types of pediatric measles
1. Mild pediatric measles: more common in infants who have received gamma globulin or adult blood injection during the incubation period, or infants who have mother antibodies in <8 months. Febrile lower upper respiratory tract symptoms are milder, pediatric measles mucosal plaque is not obvious, rash is sparse, the course of disease is about 1 week, no complications.
2, severe pediatric measles: fever up to 40 ° C or more, severe symptoms of poisoning, accompanied by convulsions, coma. The rash fusion is purple-blue, often with mucosal bleeding, such as nosebleeds, hematemesis, hemoptysis, hematuria, thrombocytopenia, etc., called black pediatric measles, may be a form of DIC; if the rash is small, the color is dim, often Poor circulation performance. This type of child has a high mortality rate.
3, rash-free pediatric measles: injection of pediatric live attenuated measles vaccine can be no typical mucosal plaque and rash, and even no rash appears throughout the course of the disease. This type of diagnosis is not easy, only relying on prodromal symptoms and serum pediatric measles antibody titers can be diagnosed.
4. Heterotypic pediatric measles: caused by inoculation of inactivated vaccine. It is characterized by high fever, headache, myalgia, and no oral mucosal plaques; the rash begins to extend to the trunk and face from the distal extremities, and is pleomorphic; often accompanied by edema and pneumonia. Domestic use of polio inactivated vaccine is not necessary, so this type is rare.
5, adult pediatric measles: due to the application of pediatric measles vaccine, adult pediatric measles incidence gradually increased, and children with pediatric measles is different: high incidence of liver damage; gastrointestinal symptoms more common, such as nausea, vomiting, diarrhea and abdominal pain Skeletal myopathy, including joint and back pain; pediatric measles mucosal plaques exist for a long time, up to 7 days, eye pain is more common, but photophobia is rare.
Examine
Pediatric examination
1. Cytology and viral antigen examination. Exfoliated cell smears of nasopharyngeal aspirate or nasopharyngeal swab or urine sediment were stained with Gemsa or HE. Under normal light microscope, multinucleated giant cells were formed and distributed in the epithelium. Eosinophilic inclusion bodies in the nucleus and in the cytoplasm. The positive rate of the first week of the disease can be as high as 90%, which has important reference value for measles diagnosis. If the above smear specimen is stained with specific antibody labeling, the measles virus antigen can be further examined.
2. Serum antibody detection Serum-specific IgM antibody is a marker of recent infection. The detection of measles IgM antibody by immunofluorescence or capture ELISA is a commonly used specific diagnostic method. Only a single serum sample is needed, 3 days after onset. It can be detected from left to right (the highest positive rate is detected 5 to 20 days after onset) and is not affected by rheumatoid factor. If the vaccine is not vaccinated in the past 1 month and the serum measles IgM antibody is positive, the diagnosis can be confirmed. Double serum from the acute and recovery phases (2 to 4 weeks after the disease), total antibodies detected by hemagglutination inhibition (H1) test and micro-neutralization test, or measles IgG antibody by ELISA, IFA, recovery period Serum antibody titer 4 times increase, has diagnostic value, can be used as a retrospective diagnosis.
The nasopharyngeal swab separates the measles virus, and large X-ray films of the lungs show large fusion lesions. The electrocardiogram sees low voltage, T wave inversion, conduction abnormality, etc. EEG examination showed a 50% abnormality.
Diagnosis
Diagnosis and diagnosis of pediatric measles
diagnosis
Diagnosis can be based on medical history, clinical symptoms, and laboratory tests.
Differential diagnosis
1. Pediatric rash infections: such as rubella, chickenpox, scarlet fever, children's acute rash, etc. should be identified with this disease. According to the history of epidemiology, the clinical symptoms of pediatric measles, the relationship between fever and rash, the characteristics of rash and related examinations, it is not difficult to identify.
2. Enterovirus infection: How to infect the Sachs virus, Echo virus, etc., mostly in the summer and autumn, the rash is diversified, can appear repeatedly, the rash retreats without scaling and pigmentation, no measles mucosal spots.
3. Drug rash: a history of useful medicine, no symptoms of measles prodromal period, rash morphology is different, the trunk is less than the limbs, and gradually recover after stopping the drug.
