Mycoplasma pneumoniae pneumonia (MPP) is an interstitial pneumonia caused by Mycoplasma pneumoniae (MP) with fever as the main symptom.
MPP is an interstitial pneumonia caused by Mycoplasma pneumoniae (MP) with fever as the main symptom, and is a common type of pneumonia in pediatric and adult patients. 10-20%, and 50% of pneumonia in children and adolescents. The disease is closely related to the onset of bronchial asthma, and studies have shown that repeated mycoplasma infections can lead to interstitial lung fibrosis and are often associated with multi-organ and multi-system damage, such as chronic bronchitis, severe pneumonia, acute respiratory distress syndrome, polyarthritis, neurological syndromes, and immune modulation disorders, and 50% of MP infections can be combined with infections from other pathogens. The first choice of Western medical treatment is erythromycin, which is effective in eliminating the symptoms and signs of mycoplasma pneumonia and has a positive efficacy, but it is not ideal for eliminating mycoplasma microorganisms and is prone to gastrointestinal reactions, which can also cause liver damage, and the course of treatment is long, which often makes it difficult for patients to accept or abandon the treatment midway. In recent years, the combination of traditional Chinese and Western medicine or simple Chinese medicine has been used to treat this disease, which has the characteristics of short course, certain efficacy and no toxic side effects.
1. Pathogenesis and epidemiology
Once named pleuropneumonia-like microorganism (PPLO), it is a pathogen without cell wall between virus and bacteria, which can pass through bacterial filter. It is currently the only minimal microorganism that can grow and reproduce on inanimate media. For growth in agar medium, cholesterol-containing yeast leachate and 20% horse serum are required. Its colonies are small and rare. Mycoplasma pneumoniae exceeds 0.5 mm and is not easily observed with the naked eye. Under the microscope the colonies are round and uniformly granular with a transparent band around the periphery. mp is in various forms such as spherical, rod-shaped and filamentous. There is only a cytoplasmic membrane consisting of three layers, and Gram staining is negative. The cytoplasm contains ribosomes and double-stranded DNA, and grows more slowly than other mycoplasmas under aerobic or anaerobic conditions, and can be seen only 5-10 days after inoculation. MP is mainly transmitted by respiratory droplets or aerosols and is mainly manifested as upper respiratory tract infection, nasopharyngitis, bronchitis and pneumonia after infection. 15% to 55% of patients are asymptomatic.
2. Pathogenesis
Both direct invasion of MP and immune damage exist, and the severity of their damage and the duration of action are still unclear, but the joint effect of the two results is certain. Recent studies have shown that the pathogenesis of MPP is related to immune mechanisms, mainly autoimmunity and immunosuppression, including humoral and cellular immunity, and studies on the mechanisms of extra-pulmonary manifestations of MPP suggest that MP antigens have the same antigenic structure as human heart, lung, liver, kidney, brain and smooth muscle, and when MP infects the body, it can generate autoantibodies in the corresponding tissues and form immune complexes to cause cross-immune reactions, leading to When MP infects the body, it can generate autoantibodies in the corresponding tissues and form immune complexes to cause cross-immune reactions, leading to lesions in the respiratory tract and other target organs outside the lungs, and the corresponding symptoms. In contrast, MPP is the result of an enhanced host immune response to mycoplasma antigens, and the antigens that cause the host response may be a complex of polysaccharide proteins. A variety of cytokines can be produced when the organism undergoes an immune response. The enhanced cell-mediated immune response and the stimulation of cytokines cause severe clinical symptoms and lung damage, and there is T-cell immune dysfunction and T-cell activation dysfunction in children with severe MPP.
3. Name of the disease in Chinese medicine
The disease is an infectious disease that occurs in all seasons, with initial manifestations of fever, dry cough, sore throat, headache, arthralgia, and peripheral discomfort, and later manifestations of irritating spasmodic cough, shortness of breath, wheezing, hematochezia, maculopapular rash, and multi-system involvement. From the perspective of the etiology of Chinese medicine, the disease should be classified as a disease caused by the six external malaise. “pneumonia cough”, “pneumonia and wheezing cough”, and “wind-warm cough”. We believe that according to its infectious characteristics, it can be classified as a “seasonal disease” or “epidemic disease”, which also fits the characteristics of “wind-warm” and “wind-warm lung fever”. “For example, in Chen Pingbo’s book on warm diseases of external influenza, it is said that “wind and temperature are the most common diseases in spring and winter, with or without vicious wind, but with fever, cough and thirst”. However, this disease occurs in all seasons, not only in winter and spring, so the name “wind-warm” seems too one-sided, so it is more appropriate to name it “seasonal cough”, which not only clarifies the properties of external fever to distinguish it from non-infectious diseases, but also reflects the symptoms of this disease with cough as the main symptom. The characteristics of the disease are
4. Etiology and pathogenesis
The main causative factors of this disease are the external invasion of evil spirits, the seasonal wind-heat, wind-cold, wind-dryness, or non-seasonal sensations, which first offend the lung guard, and then penetrate deep into the qi, ying and blood; the deficiency of positive qi is due to the weakness of the body, the lack of solidity outside the guard, or the momentary deficiency of positive qi due to sweating from fatigue, or the weakness of the internal heat and resistance to disease due to eating fragrant, dry and thick food. When the fire turns into wind and enters the camp and moves the blood, the lung loses its ability to declare and descend, then all the symptoms arise.
The lung is a delicate organ, open to the nose and up to the throat, if the lung guard is not solid, the evil invades the lung through the mouth, nose and throat, the positive and the evil fight, the guard gas is depressed, the lung gas is not declared, the purification of the order is not normal, the gas is not descending, so the cough and asthma, fever, sore throat. When wind-cold, wind-dry, wind-heat and other evils congestion in the lung, and the accumulated heat in the lung, combined with the fire to produce wind, dry the lung system, then choking and coughing, coughing even red face and throat mute, coughing, convulsions, convulsions; heat into the blood, heat forced blood, damage the lung complex, then see rash, epistaxis, hemoptysis. In the recovery period, the positive energy gradually returns, the evil energy decreases, the lung heat and fluid are injured, and the lung and large intestine are in close proximity to each other; if the lung is injured and the intestine is dry, the constipation and urination will be red, the throat is dry and mute, and the cough is short of breath.
5. Clinical manifestations
The incubation period is 3 weeks, most of them are 15-25 days, half of them are asymptomatic, the initial symptoms are similar to influenza, headache, runny nose, body discomfort, weakness, after 2-3 days the symptoms worsen, fever, chills, sore throat, body pain, cough, initially dry cough, then stubborn spasmodic cough, light day and night, even affect sleep, coughing can cause facial swelling, coughing sputum is white and sticky or purulent sputum, sometimes with blood, can be accompanied by It may be accompanied by chest tightness, retrosternal pain, dizziness, nausea, maculopapular rash or erythema nodosum. Fever is seen in more than 80% of patients, with variable fever pattern and body temperature often between 37.8 and 40°C. It may be flaccid fever or fever with a fever duration of 1 to 2 weeks. The symptoms of upper respiratory tract infection may last for 2-3 weeks, and the symptoms of pneumonia last for 4-6 weeks, followed by a recovery period with malaise and general malaise lasting for several weeks. The rash is mostly maculopapular, but other rash patterns may be seen, mostly on the trunk and extremities. 15% to 20% of MPP may also develop erythema multiforme at the beginning of the disease course. Physical examination: positive signs are rare, dyspnea and cyanosis are common in severe infections, rhinitis is common, tympanitis is common in 15% of patients, the posterior pharyngeal wall is congested, cervical lymph nodes are enlarged, croup and occasionally wet rales can be heard on auscultation of the lungs, and limited turbid sounds and bronchial croup are present on percussion in those with solid changes. Complications: The disease is often complicated by viral diseases such as EBV, herpes simplex virus, adenovirus and measles virus, as well as chlamydia, tuberculosis and fungal infections. MPP can be associated with pleurisy, interstitial pneumonia, otitis media, myocarditis, pericarditis, pancreatitis, arthritis, encephalitis, hepatitis, thrombocytopenic purpura and neurological damage, etc. MPP causes 10%-15% of childhood encephalitis, with coma, shock, movement disorders and chorea, but also cerebrospinal meningitis, and 5% of Grimballi syndrome caused by mycoplasma. In recent years, the number of severe cases of MPP has been increasing, manifested by persistent high fever, ineffective treatment with macrolide antibiotics, mediastinal pneumothorax and pneumothorax, lung necrosis in the acute phase, combined pleural effusion and pulmonary atelectasis. Sequelae: rare, may have bronchial obstruction and progressive pulmonary fibrosis.
6. Imaging characteristics
The length of time to complete recovery from imaging varies, with some treated lung lesions and lung function recovering more slowly, with a longer course, and even permanent lung damage occurring. There are complications of necrotizing pneumonia and pulmonary atelectasis. The application of high-resolution CT reveals a 37% incidence of abnormal lung images in children with MPP at a follow-up of 1 to 2 years after the disease. High-resolution CT of the lungs shows abnormalities such as “mosaic” perfusion, dilated fine bronchi, thickened bronchial walls, reduced vascular distribution, and gas trapping in the expiratory phase.
7. Laboratory and other tests
Blood picture: normal or slightly high total WBC, mildly elevated in about 25% of patients, predominantly neutrophils.
Urine routine examination: urine protein may be present in fever.
Serology: CRP is mostly elevated and positive serum IgM antibodies to mycoplasma can confirm the diagnosis.
Pathogenic examination: sputum and pharyngeal swab culture positive rate is high. PCR method is highly sensitive and facilitates confirmation of diagnosis.
X-ray examination: polymorphic infiltrative shadow, may have interstitial pneumonia or patchy fusion pneumonia changes, early interstitial pneumonia shows enhanced texture and reticulated shadow in segmental or lobular distribution, as a sign of bronchopneumonia, pneumonia foci can be completely absorbed in 4-6 weeks, 20% appear pleural effusion, often unilateral.
8. Diagnostic criteria
(1) Persistent severe cough with fever, with x-ray findings far more significant than physical signs. If several cases occur simultaneously in older children, it is suspected to be an epidemic case and the diagnosis can be confirmed early.
(2) The white blood cell count is mostly normal or slightly elevated, the sedimentation is mostly increased and the Coombs test is positive.
(3) Penicillin, streptomycin and sulfonamides are ineffective.
(4) Most of the serum agglutinins (of IgM type) have a titer of 1:32 or higher, with a positivity rate of 50% to 75%, and the more severe the disease, the higher the positivity 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 decrease and disappear in two to four months. This is a non-specific reaction, also seen in liver disease, hemolytic anemia, infectious mononucleosis, etc., but its titer generally does not exceed 1:32. Adenovirus-induced pneumonia in older children is mostly negative for cold agglutinins.
(5) X-ray examination has the following four types of changes: (1) more prominent with a thickened shadow in the hilum; (2) bronchopneumonia changes, with more in the lower and middle fields of the right lung; (3) interstitial pneumonia changes, with a reticular or striated pattern radiating from the hilum to the outer and outer bands, surrounded by small thin shadows or corn-like shadows; (4) some cases have large shadows with uneven density and a segmental distribution. A few are large lobar shadows, mostly in the lower lobe. Often, one old lesion is absorbed and another new lesion appears.
9. Treatment
MP infection is a self-limiting disease, and untreated symptoms resolve within about 10 days, but the cough and rales disappear more slowly, and antibiotic treatment can provide clinical relief as soon as possible. Moreover, early treatment and treatment with an effective dose and adequate course (14 days) of macrolipid antibiotics can prevent abnormalities in pulmonary diffusion function. Since MP has no cell wall, it is insensitive to both penicillin and other antibiotics that act on cell wall structures. Inhibition of bacterial synthesis of antibiotics such as tetracycline and macrolipids are effective antibiotics for treating MP infection. Macrolides are the first choice for treating MP infections in children, and tetracycline is known to be restricted in children under 8 years of age.
10. Chinese medicine typing and treatment
(1) Evil invading the surface of the guard
Headache and body pain, body aches, sore throat and runny nose, choking and coughing, dullness, vague chest pain, light red tongue with white fur, floating or floating pulse. The treatment method is to dredge the wind and relieve the surface, to promote the lung and throat, and the formula is based on the “Epidemic Throat Asymptote” with the addition and subtraction of Thornbush, Fanfeng, Mandarin, Almond, Peppermint, South Saxifrage, Burdock, Qianhu and Licorice; the wind-cold surface evidence is prominent, with the addition of Ephedra and Sinensis to those with vicious cold and body pain and nasal congestion and clear snot; the wind and dampness, with the addition of Atractylodes and Patchouli to those with heavy body acidity and nausea; the wind-heat surface evidence is obvious, with the addition of Shuang Hua and Lugen.
(2) Evil heat congestion of the lung
Strong heat and sore throat, choking and coughing frequently, yellow or white sputum, sticky and difficult to cough, chest pain and sweating, irritable and thirsty with dryness, red tongue with yellow coating, thin or slippery pulse. Treatment to relieve heat and detoxify the lung, clear the lung to stop coughing, the formula with the addition of flavor of Ma Heng Shi Gan Tang, if the heat is heavy plus mountain gardenia, double flowers, Qing Dai; sputum sticky cough is added Guaou Pei, golden buckwheat, aster; sore throat plus shotgun, stiff silkworm, orris, chest pain, plus Dilong, stiff silkworm, internal heat, abdominal distension and constipation, plus raw rhubarb, betel nut.
(3) Evil offending the Qi camp
Strong fever that does not subside, body heat at night, faint rash, heart trouble and sweating, coughing, yellow phlegm with blood, thirst and dry throat, red tongue with vivid coating and little dryness, thin pulse. The treatment is to clear the qi and cool the ying, purge the lung and resolve phlegm. The formula uses Qing Ying Tang and Qing Qi and Phlegm Tang with addition and subtraction, using Sheng Di, Sheng Shi Fa, Dan Pi, Xuan Shen, Mai Dong, Shui Niu Jiao, Almonds, Gua Pao, and Bile Star. Add Zi Cao, Sheng Ma for a vague spotted rash; add Xi Cao, Lotus Root, Bai Mao Root for hemoptysis; add Artemisia, Lian Qiao for the fever at night and heat in the heart of the hands and feet, or take Gua Frost Fever Reducing Spirit Capsules and Fever Inflammation Granules orally.
(4) Dry heat and Yin deficiency
The treatment is to nourish Yin and clear the lung, with the addition of Sha Shen Mai Dong Tang: Mai Dong, Sha Shen, Yu Zhu, Sang Bai Pi, Loquat leaf, Lily, Chuan Bei, Bai Qian, Bai Bai Bai. Addition and subtraction: frequent dry cough plus Ume plum and Agaricus astringent lung to stop cough, or oral nourishing Yin and clearing lung oral liquid; hot flushes and night sweats plus Artemisia annua, turtle nail to nourish Yin and remove steam, sputum less coughing unpleasant plus spinach, aster, or combined with cough suppressant.
(5) Lung spleen qi deficiency
The fever has subsided, coughing sputum is thin and white, light cough is weak, fatigue and poor appetite, abdominal distension and fullness, lack of warmth in the hands and feet, loose stools, light red tongue, white greasy coating, thin and weak pulse. The treatment is to benefit the Qi, strengthen the spleen and resolve phlegm. Addition and subtraction: poor appetite and abdominal distension, plus Buddha’s hand, Su stems, sweating and fatigue, plus Astragalus, Wu Wei Zi, sputum thin and foamy, plus Hsiang Xin, dry ginger; plain easy to catch a cold, plus Astragalus, Bai Zhu.
MPP presents endemic in most parts of the world. MP infection has a subacute and progressive course, with clinical symptoms spreading from the upper to the lower respiratory tract. The combined application of PCR and serum IgM is a sensitive and convenient method to confirm the diagnosis, and serum IgG testing has epidemiological significance. The choice of macrocyclic lipid antibiotics for treating MP infection can shorten the duration of clinical symptoms. Chinese medicine identifies the evidence from two aspects of positive deficiency and evil invasion, divided into two phases: the acute phase and the recovery phase, and the treatment is summarized into five types of evidence, such as evil invasion of the Wei surface and evil heat congestion of the lung, which can shorten the course of the disease, improve the symptoms and enhance the efficacy by combining with western macrolide antibiotics and life conditioning.