respiratory syncytial virus pneumonia in children
Introduction
Introduction to respiratory syncytial virus pneumonia in children Respiratory syncytial virus pneumonia (PS) is a common interstitial pneumonia, which occurs in infants and young children. Because maternal antibodies can not prevent the occurrence of infection, small babies born soon can be ill. It is reported that RSV accounts for 10% to 15% of neonatal viral pneumonia. The occasional nosocomial infection in foreign countries leads to the outbreak of neonatal ward in obstetric hospitals. Report. basic knowledge The proportion of illness: 0.001% Susceptible people: young children Mode of infection: droplet spread Complications: heart failure
Cause
Pediatric respiratory syncytial virus pneumonia
(1) Causes of the disease
Respiratory syncytial virus (RSV) is a syncytial virus, belonging to the paramyxoviridae family. It is the most common cause of viral pneumonia in children. It can cause interstitial pneumonia and bronchiolitis. RSV is seen under electron microscope. Similar to the parainfluenza virus, the virus particle size is about 150nm, slightly smaller than the parainfluenza virus, RNA virus, sensitive to ether, no blood cell agglutination, and formed in the human epithelial tissue to form a unique syncytium, the virus in the cell In the pulp, there is a cytoplasmic inclusion body. The syncytial virus has only one serotype. Recently, molecular biology methods have proved that there are two subtypes, A and B.
(two) pathogenesis
The incubation period of syncytial virus infection is 2-8 days (mostly 4-6 days). The typical manifestation of syncytial virus pneumonia is interstitial infiltration of monocytes, mainly manifested by alveolar septum widening and mononuclear cells. The interstitial exudation of the main, including lymphocytes, plasma cells and macrophages, in addition to the alveolar cavity filled with edema fluid, and the formation of a transparent membrane of the lung, in some cases, lymphocytic infiltration of the bronchiole wall, in the lung parenchyma There is edema associated with necrotic area, resulting in alveolar tamponade, consolidation and collapse. In a few cases, multinucleated fusion cells are seen in the alveolar space. The morphology is similar to measles giant cells, but no nuclear inclusions can be found. Gardner (1970) dissection A case of death of syncytial virus pneumonia, a large number of syncytial viruses were detected by fluorescent antibody test, and no human globulin was found. It is believed that pneumonia lesions may be mainly caused by direct infection of the syncytial virus to the lungs, not caused by allergic reactions.
Prevention
Pediatric respiratory syncytial virus pneumonia prevention
Syncytial virus is highly contagious and often causes epidemics. The literature reports that the syncytial virus infection in hospitals is as high as 30% to 50%. In autumn and winter, the temperature is fluctuating. To prevent respiratory diseases, we must first keep warm. At the same time, the autumn and winter are very dry, the air dust content is high, and the human nasal mucosa is easily damaged. Drink plenty of water to keep the mucous membrane moist. In addition, avoid going to public places with poor air circulation, and properly supplement vitamins, especially vitamin C, and pay attention to the isolation treatment of early patients. In recent years, RSV vaccine research has focused on subunit vaccines, live attenuated vaccines, peptide vaccines, genetic engineering vaccines, and nucleic acid vaccines, all of which have made some progress.
Complication
Pediatric respiratory syncytial virus pneumonia complications Complications heart failure
In severe cases, it can be complicated by heart failure and respiratory failure.
Symptom
Pediatric respiratory syncytial virus pneumonia symptoms common symptoms nasal wing fan three concave signs wheezing dyspnea high fever sound heart failure
The disease is more common in infants and young children, more than half of them are infants less than 1 year old, male to female, the ratio is about 1.5 to 2:1, the incubation period is about 4 to 5 days, coughing, nasal obstruction, about 2/3 Cases have high fever, up to 41 ° C, but fever is generally not sustainable, it is easier to fever by antipyretics, most of the hot time is 1 to 4 days, a few are 5 to 8 days, about 1/3 of the children are moderate Fever, more than 1 to 4 days, the heat history of most cases is 4 to 10 days, mild cases of breathing difficulties, neurological symptoms; medium and severe cases have obvious breathing difficulties, wheezing, cyanosis, nose fan and Three concave signs, a few severe cases can also be complicated by heart failure, chest auscultation is mostly small or thick, middle voice, percussion is generally no voiced, a few have had a voiceless, in 1998, the Capital Institute of Pediatrics on 22 cases of pathogen A subtype The clinical features of children with RSV bronchiolitis were initially summarized. The children were mainly infants, 82% of infants aged 1 to 6 months, 4.5:1 males and females, and fever was generally lower than 38 °C. 54%), wheezing (64%) after 2 days of onset, chest X-ray mainly showed two lungs (77%) and Emphysema (64%).
Examine
Examination of respiratory syncytial virus pneumonia in children
1. The total number of leukocytes in blood is generally (5 ~ 15) × l0 9 / L, most of them are below 10 × 10 9 / L, and neutrophils are more than 70%.
2. Virology and serological examination The diagnosis of this disease is mainly based on the results of virology and serological examination. In recent years, indirect immunofluorescence technique using ELISA for exfoliated cells of nasopharyngeal secretions and serum, ELISA, alkaline phosphatase and alkali resistance Phospho-phosphatase-bridged enzyme labeling (APAAP), biotin avidin ELISA, horseradish peroxidase-anti-horseradish peroxidase (PAP), monoclonal antibody fluorescence, etc. Rapid diagnosis of viral infections.
X-ray examination: Most of them have small flaky shadows, and large pieces are extremely rare. About 1/3 (partial) of the sick children have different degrees of emphysema.
Diagnosis
Diagnosis and diagnosis of respiratory syncytial virus pneumonia in children
The initial diagnosis is based on clinical manifestations and X-ray features. At present, early diagnosis can be confirmed by immunofluorescence technique or immunoenzyme technology.
In the past ten years, respiratory syncytial virus pneumonia and bronchiolitis accounted for the first place in infants and young children with viral pneumonia. The symptoms are almost indistinguishable from the parainfluenza pneumonia, mild influenza virus pneumonia and mild adenovirus pneumonia. Viral pneumonia and severe adenovirus pneumonia continue to have high fever, severe symptoms of poisoning and respiratory symptoms, and clinical manifestations are far more serious than syncytial virus pneumonia. The clinical symptoms of syncytial virus pneumonia are similar to those of general bronchopneumonia, and mild adenovirus pneumonia. It is also difficult to distinguish, the diagnosis needs to be considered in combination with the results of the virus test. Pediatric respiratory syncytial virus pneumonia should be differentiated from rhinitis, pharyngitis, laryngitis, bronchiolitis.
