Pediatric mycoplasma pneumonia
Mycoplasma pneumonia, also known as primary atypical pneumonia and condensation-positive pneumonia, is an inflammatory disease of the lungs caused by mycoplasma (MP) infection with interstitial pneumonia and capillary bronchitis-like changes that manifests clinically as intractable and severe cough. MP is one of the important pathogens of pneumonia and other respiratory infections in childhood.
Etiology
The main pathogen of the disease is Mycoplasma pneumoniae, the smallest of the pathogenic microorganisms known to live independently between bacteria and viruses, which can pass through bacterial filters. The pathogen is 125-150mm in diameter, similar in size to a mucovirus, and has no cell wall, so it is spherical, rod-shaped, filamentous, and other forms, and is Gram-stain negative. It is resistant to freezing and can only survive for a few hours at 37°C.
Clinical manifestations
1. The incubation period is about 2 to 3 weeks (8 to 35 days).
2. The symptoms vary in severity. Most of them are not urgent, with fever, anorexia, cough, chill, headache, sore throat and pain under the sternum. The body temperature is 37-41℃, most of them are around 39℃, which can be persistent or flaccid, or only low fever, or even no fever. Most of the cough is heavy, initially dry, followed by sputum (occasionally containing a small amount of blood), and sometimes paroxysmal cough slightly resembling whooping cough. Nausea, vomiting and transient maculopapular rash or urticaria are occasionally seen. There is usually no respiratory distress, but infants may have wheezing and dyspnea.
Signs vary according to age, with older children often lacking significant chest signs. In infants, there may be mild turbid tones on percussion, decreased breath sounds, and wet stalls.
4. The natural course of the disease varies from a few to 2-4 weeks, with most fevers resolving in 8-12 days and recovery taking 1-2 weeks. Occasionally, recurrence is seen.
Examination
X-rays mostly show unilateral lesions, mostly in the lower lobe, sometimes only with increased shadowing in the hilum, mostly with uneven cloudy pulmonary infiltrates extending outward from the hilum to the lung fields, especially common in the lower lobe of both lungs, with a few large lobar solid shadows. Pulmonary atelectasis may be seen. The infiltrates often dissipate in one area while new infiltrates occur elsewhere. Sometimes there is a bilateral diffuse reticular or nodular infiltrative shadow or interstitial pneumonia without solid lung segments or lobar changes. Mild signs with prominent chest radiograph shadows are a characteristic feature of the disease.
Diagnosis
The main diagnostic points are.
1. Persistent and severe cough with far more significant radiographic findings than physical signs. If several cases occur simultaneously in older children, an epidemic case is suspected and the diagnosis can be confirmed early.
2. The white blood cell count is mostly normal or slightly elevated, the blood sedimentation is more rapid, and the Coombs test is positive.
3. Penicillin, streptomycin and sulfonamides are ineffective.
4.Serum agglutinin (IgM type) titers mostly rise to 1:32 or higher, the more severe the disease, the higher the positive rate. Cold agglutinins mostly appear at the end of the first week after the onset of the disease, reaching a peak in the third to fourth week, and then gradually decrease and disappear in two to four months.
5.Serum specific antibody determination has diagnostic value and is often used clinically by complement binding test, indirect hemagglutination test, indirect immunofluorescence method and enzyme-linked immunosorbent assay. In addition, enzyme-linked adsorbent assay can be used to detect antigen. In recent years, the application of DNA probes and PCR detection of Mycoplasma pneumoniae DNA diagnosis at home and abroad has the advantage of high rapidity and specificity.
6, with the patient’s sputum or pharyngeal wash culture mycoplasma takes too long, often 2 to 3 weeks, so it is not very helpful for clinical purposes.
Treatment
The treatment of pediatric MP pneumonia is based on the same principles as that of general pneumonia, with comprehensive therapeutic measures. It includes five aspects: general treatment, symptomatic treatment, application of antibiotics, adrenocorticosteroids, and treatment of extra-pulmonary complications.
1.General treatment
(1) respiratory isolation: Because mycoplasma infection can cause a small epidemic, and the time of mycoplasma discharge after the disease in children is long, up to 1 to 2 months beyond. The affected child or children with a history of close contact should be respiratory isolated as much as possible to prevent reinfection and cross-infection.
(2) Care: Keep the room air fresh, supply easily digestible, nutritious food and adequate fluids. Keep the oral hygiene and respiratory tract unobstructed, turn the child frequently, pat the back, and change the position to promote the discharge of secretions, and if necessary, aspirate appropriately to remove mucous secretions.
(3) Oxygen therapy: for those with serious condition and hypoxia, or those with serious airway obstruction, oxygen should be given in time.
2.Symptomatic treatment
(1)Expectoration: The purpose is to make the sputum thin and easy to discharge, otherwise it is easy to increase the chance of bacterial infection. In addition to strengthening turning, back patting, nebulization and sputum aspiration, expectorant can be used.
(2) Asthma: For those with severe asthma, bronchodilators such as aminophylline can be used orally, and albuterol inhalation can also be used.
3.Application of antibiotics
Antibiotics that can inhibit protein synthesis should be used, including macrolides
4.Application of adrenal glucocorticoids
For the acute stage of the rapid development of severe MP pneumonia or lung lesions that extend and appear pulmonary atelectasis, interstitial fibrosis, bronchiectasis or extra-pulmonary complications, adrenal corticosteroids can be applied. For example, hydrocortisone or hydrocortisone succinate, dexamethasone, prednisone, etc. Care should be taken to exclude infections such as tuberculosis when applying hormones.
Is mycoplasma pneumonia contagious in children?
The incidence of mycoplasma pneumonia has increased significantly in recent years, with an incubation period of 2 – 3 weeks. The incubation period and the respiratory tract carry the bacteria for a long time, the surrounding population has more opportunities to be infected, and there are more extra-pulmonary complications such as encephalitis, hepatitis, myocarditis, etc. Therefore, it is important to strengthen the prevention of this disease.
Mycoplasma pneumoniae pneumonia is less contagious than influenza and measles, therefore, early isolation of patients can play a certain preventive effect. During the epidemic of mycoplasma pneumonia, children in contact with patients can be given oral erythromycin 20-40mg/kg/day in 3-4 doses for 3 days, which can play a preventive role.
Can pediatric mycoplasma pneumonia be cured?
Mycoplasma pneumonia, also known as primary atypical pneumonia, is caused by Mycoplasma pneumoniae, which is smaller than bacteria and larger than viruses. Although the symptoms of mycoplasma pneumonia are severe, it can be cured.
The application of macrolide antibiotics often have special effects, such as: erythromycin, azithromycin, cross-sampling, rolithromycin and other good results, while penicillin, vanguardomycin is not effective. The course of treatment is generally appropriate for 2 weeks, and can be extended to 3-4 weeks in severe cases. Other symptomatic treatments include cough suppression, cough suppression and herbal treatment. Extra-pulmonary symptoms should be treated appropriately.
If the treatment is inappropriate and does not follow the regular treatment of mycoplasma infection, recurrent respiratory infections and the potential for asthma may occur after the acute phase.
Treatment of mycoplasma pneumonia in children
Mycoplasma pneumonia in children has an acute onset, so reasonable and timely treatment is especially important.
In case of high fever, take antipyretic medication as required by the doctor. If the body temperature is above 38.5℃, take it once every 4-6 hours, and give the child more water after taking antipyretic medication to help sweat out the fever. You can also use physical cooling method, such as alcohol bath, cold water bag on the forehead, etc. For malnourished, weak children, it is not appropriate to take antipyretic drugs or alcohol bath, available warm water bath to cool down, or Chinese medicine to clear the heat, such as pediatric Niuhuang San, Zixue San, etc.;
2, even if the temperature has not subsided, we should try to avoid several trips to the hospital a day, otherwise the child will not get rest, the hospital is concentrated in the patients, the air is not good, easy to re-infection of other diseases. It is not good for the child’s recovery;
3, home medication and care process, found that the child irritable, gray, sweating, blue around the mouth, pulse significantly accelerated, should be immediately sent to the hospital, do not delay the time of treatment of the damage to the heart function. You need to go to the hospital for further examination and treatment;
4, after pneumonia is healed, do not take it lightly, pay special attention to the prevention of upper respiratory tract infections, otherwise prone to recurrent infections. Attention must be paid to strengthening exercise. Do not take your child to public places when the flu is prevalent. When someone in the family has a cold, you should also try to avoid contact with your child.