Bronchopneumonia in children
Introduction
Introduction to bronchial pneumonia Bronchial pneumonia is a major common disease in children, especially in infants and young children, and it is also the main cause of death in infancy. Bronchial pneumonia, also known as lobular pneumonia, occurs mostly in the cold seasons of winter and spring and sudden changes in climate, but summer is no exception. Even some southern China have more incidences in the summer, and the immunity is not persistent after the illness, and it is easy to be infected again. Bronchopneumonia is caused by bacteria or viruses. basic knowledge The proportion of illness: 30% Susceptible people: children Mode of infection: non-infectious Complications: myocarditis, pericarditis, hemolytic anemia, thrombocytopenia, meningitis, hepatitis, gastrointestinal bleeding
Cause
Causes of bronchopneumonia in children
Probability factor (35%):
Pneumonia is easy to occur in infants and young children due to physiological and anatomical features of the respiratory system, such as trachea, bronchial lumen stenosis, less mucus secretion, poor ciliary movement, poor development of lung elastic tissue, rich blood vessels and easy congestion, strong interstitial development, and number of alveoli Less, less lung gas, easy to block for mucus, etc., there are also weaknesses in immunology at this age, defense function has not been fully developed, prone to infectious diseases, malnutrition, rickets and other diseases, these internal factors not only make infants and young children easy Pneumonia occurs, and it is more serious. The immunity of infants under 1 year old is very poor. Therefore, pneumonia is easy to spread, and it spreads and spreads to both lungs. Children older and stronger have more mature body reactivity, limited infection ability, and pneumonia. Larger lesions often appear, such as large leaf pneumonia if limited to one leaf.
Pathogen infection (35%):
Bronchopneumonia can be induced by pathogens that cause upper respiratory tract infections, but mainly by bacteria and viruses. Among them, Streptococcus pneumoniae, Haemophilus influenzae, and RSV are the most common. After the 1990s, the United States and other developed countries generally vaccinate. Haemophilus influenzae type b (Hib) vaccine, thus the pneumonia caused by Haemophilus influenzae has been significantly reduced, the majority of bronchial pneumonia is caused by pneumococcal bacteria, accounting for more than 90% of bacterial pneumonia, other bacteria such as staphylococcus, chain Cocci, influenza bacillus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa are rare, pneumococci have at least 86 different serotypes, all of which are sensitive to penicillin, so the current classification is of little significance for treatment, Common pneumococcal types are types 14, 18, 19, and 23.
The virulent pneumococci are capsule-bearing and contain type-specific polysaccharides, which are resistant to phagocytosis, while asymptomatic pneumococcal-borne carriers play a more important role in spreading infection than pneumonia patients. The disease is generally sporadic, but sometimes it can be prevalent in the group care institutions. Beta-hemolytic streptococcus often appears as a secondary infection in the course of measles or whooping cough. Coagulase-positive Staphylococcus aureus is a common pathogen of severe pneumonia in children. However, staphylococcus aureus pneumonia has increased in recent years. Pneumonia caused by influenza bacilli is often secondary to bronchitis, bronchiolitis or sepsis. It is more common before 3 years old. Pneumonia caused by Escherichia coli is mainly seen in newborns and Malnourished babies, but in the case of a large number of antibiotics in recent years, the disease is the same as staphylococcal pneumonia, which can be secondary to other serious diseases. Pneumococcal pneumonia and Pseudomonas aeruginosa pneumonia are rare, generally For secondary, interstitial bronchial pneumonia is mostly caused by viruses, mainly adenovirus, respiratory syncytial virus Influenza virus, parainfluenza virus, measles virus, etc., measles pneumonia often occurs in the course of measles, but the measles virus itself can also cause pneumonia. I have isolated measles virus from the lungs of early death of measles pneumonia without bacterial infection, interstitial bronchus Pneumonia can also be caused by certain types of influenza bacilli, pertussis bacilli, Streptococcus viridans and Mycoplasma pneumoniae.
Pathogenesis
Due to congestion of the airways and alveolar walls, edema and exudation, resulting in airway obstruction and thickening of the respiratory membrane, and even alveolar tamponade or collapse, causing hypoxemia and/or hypercapnia, respiratory failure, and Cause extensive damage to other systems, such as heart failure, cerebral edema, toxic encephalopathy, toxic intestinal paralysis, gastrointestinal bleeding, dilute hyponatremia, respiratory acidosis and metabolic acidosis, etc., generally considered to be toxic Myocarditis and pulmonary hypertension are the main causes of heart failure. However, in recent years, studies have shown that there is no decrease in myocardial contractility in children with pneumonia, and an increase in angiotensin II level and an increase in cardiac afterload may play an important role. Severe pneumonia combined with inappropriate antidiuretic hormone secretion syndrome can also cause non-cardiac circulation hyperemia symptoms.
Prevention
Prevention of bronchopneumonia
1. Strengthen nursing and physical exercise
Infants should pay attention to nutrition, add non-staple food in time, cultivate good diet and hygienic habits, and get more sun. Preventing rickets and malnutrition is the key to preventing severe pneumonia. From a small exercise, indoors should be ventilated, often in outdoor activities or sleeping outdoors, so that the body is resistant to cold and adapt to changes in environmental temperature, it is not easy to have respiratory infections and pneumonia.
2, to prevent acute respiratory infections and respiratory infections
Infants and young children should be able to avoid contact with respiratory infections, especially weak infants can easily develop into pneumonia after infection. Pay attention to the prevention of respiratory infections that are prone to severe pneumonia, such as pertussis, influenza, adenovirus and measles. Especially for children with immunodeficiency diseases or with immunosuppressive agents.
3. Prevention of complications and secondary infections
Infants with pneumonia have weak resistance and are susceptible to other diseases. They should actively prevent complications that may cause serious prognosis, such as empyema and pus. Children with different pathogens should be isolated as much as possible in the ward. Children in the recovery period and new admission should also be separated as much as possible. When medical personnel are exposed to different children, attention should be paid to disinfection and isolation. In recent years, there have been reports on the use of Chinese herbal medicines such as Atractylodes lancea and Ai Ye to reduce pathogens in the air. This method can be used to prevent cross-infection.
Complication
Pediatric bronchopneum complications Complications Myocarditis Pericarditis Hemolytic anemia Thrombocytopenia Meningitis Hepatitis Digestive tract bleeding
Delayed diagnosis or pathogen virulence (such as Staphylococcus aureus infection) can cause complications such as myocarditis, pericarditis, hemolytic anemia, thrombocytopenia, meningitis, hepatitis, pancreatitis, splenomegaly, digestive tract Bleeding, nephritis, hematuria, proteinuria, etc., such as in the treatment of pneumonia, symptoms of poisoning or difficulty in breathing suddenly aggravated, body temperature continues to retreat or retreat, should consider the possibility of complications, such as empyema, pus , lung bullae and so on.
Symptom
Pediatric bronchial pneumonia symptoms common symptoms irritability, pleural effusion, pediatric cough, dyspnea, dysphonia, respiratory failure, jugular vein dysfunction, circulatory failure
General pneumonia
The clinical manifestations of typical pneumonia include:
(1) General symptoms: sudden onset or slow onset, sudden onset of fever, vomiting, irritability and wheezing, etc., before the onset of mild upper respiratory tract infection for several days, early body temperature is mostly 38 ~ 39 ° C, Can also be as high as 40 °C, mostly relaxation or irregular fever, neonatal can not fever or body temperature does not rise, weak infants mostly slow onset, fever is not high, cough and lung signs are not obvious, common milk, Vomiting or difficulty breathing, licking milk is sometimes very noticeable, and can be spilled through the nostrils each time you feed.
(2) Cough: cough and pharyngeal snoring, usually obvious at early stage, early dry cough, extreme cough can be reduced, coughing increases during recovery, there are sputum, newborns, premature babies can have no cough, only performance Spitting foam and so on.
(3) shortness of breath: more often occurs in fever, after coughing, superficial breathing, respiratory rate is accelerated (>60 times/min in 2 months, 2~12 months>50 times/min, l~4 years old>40 Times/min), when the severely ill is breathing, the cyanosis may occur, and the ratio of breathing to pulse increases from 1:4 to about 1:2.
(4) Difficulty breathing: common dyspnea, perioral or nail cyanosis and nose flapping, heavy ones have nodular breathing, three concave signs, prolonged expiration time, etc. Some sick children head backwards to breathe more smoothly, If the child is passively flexed forward, the resistance is obvious, and this phenomenon should be distinguished from the cervical muscle rigidity.
(5) Fixing the wet and squeaky sound of the lungs: The early signs of the chest signs may not be obvious or the breath sounds may be rough or slightly reduced. In the future, the sounds can be heard and fixed, and the wet sounds or sputum sounds are often heard during crying and deep breathing. Yes, the percussion is normal or there is a slight percussion dullness or reduced breathing sound, but when the lesion fusion enlarges part or the whole lobe, the corresponding lung consolidation signs may appear, if one side of the lung is found to have obvious percussion dullness and/or Lowering the breath sound should consider the presence or absence of pleural effusion or empyema.
2. Severe pneumonia
Severe pneumonia, in addition to the serious involvement of the respiratory system, can also involve the system of circulation, nerves and digestion, and the corresponding clinical manifestations appear:
(1) Respiratory failure: Early manifestations are the same as pneumonia. Once respiratory rate is slowed down or neurological symptoms should be considered respiratory failure, blood gas analysis should be performed in time.
(2) Circulatory system: heart failure in children with severe pneumonia, manifested as:
1 The respiratory rate suddenly increased, more than 60 times / min,
2 heart rate suddenly increased, >160~180 times/min,
3 sudden irritability, obvious cyanosis, pale complexion, finger (toe) microvascular filling time is prolonged,
4 heart sounds are low and blunt, galloping, jugular vein anger,
5 The liver is significantly enlarged or rapidly increases in a short time,
6 oliguria or no urine, facial eyelids or lower extremity edema, the above performance can not be explained by other reasons that should consider heart failure, fingertip venous network filling, or facial, limb edema, it is a sign of congestive heart failure, Sometimes the limbs are cold, the mouth is gray, and the pulse is weak, which is the peripheral circulatory failure.
(3) nervous system: mild hypoxia is common manifestation of irritability, lethargy, many young babies in early convulsions, mostly due to high fever or calcium deficiency, such as convulsions with obvious symptoms of lethargy and poisoning or persistent coma, and even Occurrence of tonic spasm, hemiplegia or other brain signs may be complicated by central nervous system diseases such as meningoencephalitis or toxic encephalopathy, cerebral edema, disturbance of consciousness, convulsions, irregular breathing, anterior hernia, meningeal irritation, etc., but The cerebrospinal fluid test is basically normal.
(4) digestive system: mild pneumonia often has loss of appetite, vomiting, diarrhea, etc., severe cases can cause paralytic ileus, abdominal distension, bowel sounds disappear, abdominal distension can be caused by hypoxia and toxins, severe diaphragmatic rise, oppression Chest, severe breathing can be more severe breathing, sometimes lower lobe pneumonia can cause acute abdominal pain, should be differentiated from abdominal surgical diseases, vomiting coffee slag samples when gastrointestinal bleeding, fecal occult blood positive or tar-like stool.
Examine
Examination of bronchopneumonia in children
Blood picture
Peripheral blood leukocyte counts and differential counts have certain value for judging bacteria or viruses. Most of the above indicators of bacterial infections are increased, while most of the viral infections are normal. The total number of peripheral blood leukocytes in the patients with mycoplasma infection is mostly normal or high, and the classification is mainly neutrophils. However, in severe S. aureus or Gram-negative bacilli pneumonia, white blood cells can be increased or decreased.
2. Specific pathogenic examination
(1) Nasopharyngeal aspirate or sputum specimen:
1 virus detection: early in the viral pneumonia, especially within 5 days, the nasopharyngeal aspirate or sputum (shed epithelial cells) can be collected for virus detection. At present, most of the virus antigens in the nasopharyngeal exfoliated cells are determined. Early rapid diagnosis of DNA or RNA,
2 Bacterial examination: bacteriological examination of children with pneumonia is more difficult, because there are a large number of normal flora in the pharynx, and the removal of lower respiratory tract specimens will inevitably be contaminated, so the results of respiratory secretion culture are for reference only. Absorption of nasopharyngeal secretions from throat swabs or sterile catheters for bacterial culture and drug susceptibility testing can provide a basis for early selection of antibiotics.
(2) Blood specimen: The positive rate of blood and pleural effusion culture is very low. If there are symptoms of sepsis at the same time, blood culture should be done. Children with relatively long course of disease should be serologically examined by collecting blood samples to determine serum specific IgM. Early rapid virological diagnosis, virus isolation and acute/restorative double serum antibody determination are the most reliable basis for the diagnosis of viral infection, but it is time-consuming and labor-intensive and cannot be used in clinical practice.
(3) pleural effusion examination: when pleural effusion occurs, it can be used for chest puncture, pleural effusion culture and smear examination, generally 30% of pneumococcal pneumonia cases.
4) Others: The application of fiberoptic bronchoscopy, especially the application of protective brush, can reduce the pollution rate to less than 2%, which has a good application prospect. Pulmonary puncture culture is the gold standard for diagnosing bacterial pneumonia. Both children and doctors are not easy to accept. Vuori Holopainen recently reviewed the lung puncture and concluded that the technique has advantages that are unmatched by other methods. The pneumothorax is often asymptomatic and can be recovered naturally. It can still be considered in some institutions.
3. Mycoplasma detection
Mycoplasma detection is similar to virus. In the early stage, throat swab specimens can be directly collected for mycoplasma antigen or DNA detection. The elderly patients can be diagnosed by measuring serum-specific IgM.
4. Non-specific pathogenic examination
Such as peripheral blood white blood cell count and differential count, blood leukocyte alkaline phosphatase score, tetrazolium blue test, etc., may have certain reference value for judging bacteria or viruses, bacterial infections are mostly increased above, while viral infections are mostly normal, mycoplasma The total number of white blood cells in the peripheral blood of infected people is mostly normal or high. The classification is mainly neutrophils, blood C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 (IL-6) and other indicators. Bacterial infections are mostly increased, while viral infections are mostly normal, but there is a large overlap between the two, the identification value is not large, such as the above indicators significantly increased, it is strongly suggested that bacterial infection, blood cold agglutinin test > 1:32 for mycoplasma Pneumonia has an auxiliary diagnostic value.
5. Blood gas analysis
It is of great significance to assess the severity of pneumonia, prognosis and guiding treatment.
6. X-ray inspection
The causes of bronchial pneumonia are different, so the changes on the X-ray have both commonalities and their own characteristics. In the early stage, the lungs are thickened, and small patchy shadows appear later. And the heart area is mostly, and may be accompanied by atelectasis or emphysema, patchy shadows can also be merged into large pieces, and even spread the entire segment.
(1) Morphology of the lesion: bronchial pneumonia is mainly caused by inflammatory exudation in the alveoli, and it spreads along the bronchus and invades the lobules, lung segments or large leaves. X-ray signs can be expressed as non-specific small patchy lung parenchymal infiltration shadows. In the two lungs, the palpebral horn area and the middle belt are more, this change is common in infants under 2 years old, small patch lesions can be partially fused together into a large infiltrating shadow, even similar to segments or large The form of leaf pneumonia, if there are more small round lesions in the lesion, it should be considered that there may be a variety of mixed purulent infections.
(2) Atelectasis and emphysema sign: Partial atelectasis or emphysema can occur due to obstruction of bronchial endocrine secretions and pneumonia. Emphysema is one of the early signs of common symptoms in children with pneumonia. The more severe the symptoms of poisoning, the more obvious emphysema, and the chance of bubbling emphysema and mediastinal emphysema during the course of the disease is more common than that of adults.
(3) X-ray signs of pulmonary interstitial: the interstitial tissues of infants are well developed. When suffering from bronchial pneumonia, some X-ray signs of interstitial lung may appear. Commonly, the texture of the internal lungs is increased, blurred, and influenza virus pneumonia. These X-ray signs can be found in the interstitial inflammatory response caused by measles virus pneumonia and pertussis pneumonia.
(4) hilar X-ray sign: Most of the lymph nodes around the hilar are not swollen or only show darkening of the hilar, even moist around the hilum.
(5) X-ray signs of the pleura: less pleural changes, sometimes one or bilateral pleurisy or pleural effusion, although the bronchial pneumonia of different causes have similarities in X-ray performance, only To be the same, therefore, it is necessary to master the X-ray manifestations of various pneumonias, and to closely combine clinical symptoms in order to make a correct diagnosis.
7.B-ultrasound
There may be liver enlargement when there is liver damage or hepatic bleeding.
8. ECG examination
With or without myocardial damage.
Diagnosis
Diagnosis and diagnosis of bronchial pneumonia
diagnosis
According to the typical clinical symptoms, combined with X-ray chest X-ray, the diagnosis is not difficult, according to acute onset, respiratory symptoms and signs, if necessary, can do X-ray, chest or throat swab, tracheal secretion culture or virus separation, When the white blood cells are significantly elevated, it can assist in the diagnosis of bacterial pneumonia. If the white blood cells are reduced or normal, they are mostly viral pneumonia.
Differential diagnosis
It needs to be differentiated from tuberculosis, bronchial foreign body, asthma and infection, and should be evaluated for its severity, complications and possible pathogens.
Tuberculosis
Symptoms of active tuberculosis and X-ray films, similar to bronchial pneumonia, should pay attention to the history of family tuberculosis, tuberculin test and long-term clinical observation, and should pay attention to pulmonary tuberculosis and clinical symptoms. Less, the two are often disproportionate.
2. Other conditions in which breathing difficulties occur
The diseases of the laryngeal obstruction generally show symptoms such as hoarseness. If the breathing of the sick child is deepened, it should be considered whether it is accompanied by acidosis. The breathing difficulty of asthma is heavy when exhaling. Although the infant's paroxysmal tachycardia is short of breath, cyanosis Such symptoms, but with the characteristics of sudden onset of tachycardia, can also be checked by electrocardiogram.
