Pediatric parainfluenza virus pneumonia
Introduction
Introduction to Pediatric Parainfluenza Pneumonia Parainfluenza virus pneumonia is widely found in nature due to parainfluenza virus. It can cause disease throughout the year, which can cause different upper and lower respiratory tract infections in children, such as colds, otitis media, severe laryngeal tract, trachea, bronchitis, and bronchiolitis. And pneumonia. Parainfluenzalpneumonia is similar to respiratory syncytial virus pneumonia and is more common in infants with pneumonia. basic knowledge The proportion of illness: 3% Susceptible people: children Mode of transmission: airborne Complications: meningitis
Cause
Pediatric parainfluenza pneumonia
(1) Causes of the disease
Parainfluenza virus belongs to the family Paramyxoviridae, RNA virus, human-related parainfluenza virus is divided into 4 types: There are two types in type 1, namely, blood cell adsorption type 2 virus (HA2) and Sendai virus (HVJ); Type 2 is croup virus (CA); type 3 is blood cell adsorption type 1 virus (HA1); type 4 also has two types of strains, A and B (M25), type 1, 2, 3 can cause mild rhinitis, pharyngitis And bronchitis; type 1,2 can cause severe laryngitis (croup), more common in children 2 to 6 years old; type 3 can cause pneumonia and bronchiolitis, more common in infants less than 1 year old, as for Sendai virus, 1952 In Japan and 1953 in Japan, there were a few reports of pneumonia in the Vladivostok in the Soviet Union in 1955, but foreign countries have doubts about human diseases. In China, Beijing has found infant pneumonia, bronchiolitis, upper respiratory tract infection Sendai virus The recovery period antibody is increased more than 4 times, and the virus is isolated. Therefore, the pathogenicity of Sendai virus to humans should be affirmed. Parainfluenza virus is the viral pathogen of infant pneumonia and bronchiolitis, and it has been in the north in recent years. Cytovirus and adenovirus are the third, second only to the south Cytomegalovirus, for the first two,
(two) pathogenesis
Parainfluenza viruses are mainly transmitted through respiratory secretions and spread through aerosols in the air. Parainfluenza viruses are relatively active in cold, dry environments, so parainfluenza infections occur mostly in winter and spring.
Prevention
Pediatric parainfluenza virus prevention
The prevention of parainfluenza virus is similar to that of SARS and influenza. It should develop good living habits and hygienic habits to prevent all respiratory infections, such as diligent ventilation, diligent exercise, frequent hand washing, drink plenty of water, increase or decrease clothing in time, and visit patients. Wear masks, avoid coughing, sneezing, maintain personal and environmental hygiene, and improve the body's ability to resist various diseases. Some people in foreign countries have conducted research on subunit vaccines, but it still takes a certain time from practical application. Parainfluenza virus type 3 live vaccine can be used as a preventive application.
Complication
Pediatric parainfluenza pneumonia complications Complications meningitis
Can be combined with bacterial infections, generally no other comorbidities, young children with poor immunity may have complications after infection, such as meningitis, young infants can cause asphyxia and respiratory failure due to acute laryngotracheal bronchitis.
Symptom
Pediatric parainfluenza pneumonia symptoms Common symptoms Bacterial infections, high fever, wheezing, wet voice, dyspnea, low fever
From 1962 to 1964, the symptoms of Sendai virus pneumonia, which increased in serum during the recovery period in Beijing, were 4 to 8 days, most of which were 3 to 5 days. During this period, the high fever time was short, and the cough was not severe. There was laryngitis in the case, mild dyspnea, and scattered voice in the lungs, but most of the percussives had no voiced sounds. X-ray examination showed small patches of shadows, absorbed within 1 to 3 weeks, and other types were observed. Pneumonia caused by influenza virus, the symptoms are similar to those caused by the above Sendai virus. From 1975 to 1980, the Institute of Pediatrics of the Chinese Academy of Medical Sciences saw more than 4 times higher serum antibody than the type 3 parainfluenza virus, and a few Type 2 and Sendai virus, the clinical manifestations of these infants and young children with pneumonia are similar to those seen in 1962-1964. Most of the cases are mild. Foreign reports, clinical manifestations and syncytial virus of type 3 parainfluenza virus infection in infants under 1 year old The infection is very similar. When you get sick, you have symptoms of cold, runny nose, low fever, cough, and then cough increases, there is convulsion, breathing is quick, the lungs smell dry and wet, and wheezing, combined with bacterial infection. Warm and high fever, severe symptoms of poisoning, obvious wheezing, it is currently impossible to make a specific diagnosis of parainfluenza in clinical practice. When needed, the virus can be isolated and identified by tissue culture inoculation, and the respiratory tract can also be detected by immunological and molecular biological techniques. The viral antigen in the infected cells is tested for complement fixation in the acute phase and convalescent sera. The hemagglutination inhibition reaction neutralization test can confirm the parainfluenza virus infection, but if the virus is not isolated, due to the serological cross-reactivity, It is difficult to identify a specific virus type.
Examine
Pediatric parainfluenza pneumonia check
Rapid diagnosis of viral antigens can be detected by direct or indirect immunofluorescence techniques, and can also be detected by RIA, enzyme-labeled antibody staining or ELISA. The diagnosis requires virus isolation or serological examination. The virus is isolated from the pharynx, so the virus can be isolated from the pharynx and nasal secretions to determine the pathogen. When the virological diagnosis is made, the nasopharyngeal secretions or throat swab specimens of the child should be taken early in the onset. The positive rate of monkey kidney cells was the highest, and the lesions were observed in type 1 and type 3 for 3 to 7 days, which could be identified by blood cell adsorption. The type 2 and 4 cultures were longer, only type 2 could be seen to express cells, and serum diagnosis could be inhibited by hemagglutination. In the test, even the first onset may have type 1, 2, 3 and mumps virus homologous and heterotypic antibodies at the same time; isotype and / or heterotypic antibodies may also rise when reinfected; but sometimes nasopharyngeal secretions The virus is positively isolated, but no antibody rises. There is little understanding about the rise of type 4 virus antibodies. Only the first type of infection often has the same type of antibody rise, clinical requirements for rapid diagnosis, rapid diagnosis of acute phase is available. Excipient smear or tissue immunofluorescence to check antigen, can also be applied RIA, enzyme-labeled antibody staining, complement fixation, hemagglutination inhibition or ELISA, X-ray lung weight gain, double-lung lung visible dot shadow Alveolar hyperinflation, combined with bacterial infection, visible signs of consolidation.
Diagnosis
Diagnosis and identification of pediatric parainfluenza virus pneumonia
The most common form of acute febrile respiratory infection in children is clinically indistinguishable from influenza or other respiratory viral infections in the same age group. It is caused by fever and nasal congestion, runny nose, etc., with moderate sore throat and dry cough. Many cases of hoarseness and snoring (caused by acute laryngotracheitis, the most serious and dangerous condition of pediatric parainfluenza infection), the disease is often not associated with respiratory syncytial virus pneumonia and small infants under 5 months Adenovirus pneumonia is identified, but the condition of infants and young children is significantly lighter than 6 months. Sometimes it is not easy to distinguish from pneumococcal pneumonia under antibiotic treatment. Leukocytosis and neutrophil alkaline phosphatase increase can help the diagnosis of the latter. .
