Mycoplasma respiratory infection is an acute respiratory tract infection characterized by the development of bronchopneumonia. Respiratory mycoplasmosis is a very common disease. There is a wave-like rise in morbidity with a frequency of 1 every 2-4 years. There is seasonality: the peak incidence occurs during the cold season. Mycoplasmoses account for 6-22% of all acute pneumonia and 5-6% of respiratory tract diseases. During periods of epidemic outbreaks, the proportion of mycoplasma infections among respiratory diseases can reach 50%.
Mycoplasma pneumoniae is the causative agent of mycoplasma respiratory infection. Mycoplasmas are microorganisms that do not have a cell wall, which are embedded in the cellular structure of the host body tissue. Mycoplasmas of various species are isolated from plants, human and animal tissues. For 14 mycoplasma species, humans are the natural host. Mycoplasma pneumoniae stands out for its ability to produce hemolysin and hemaglutinins, and ferment carbohydrates. Mycoplasma in aerosols indoors can remain viable for up to half an hour, at 4 ° C – 37 hours, at 37 ° C – 5 hours. Microorganisms are sensitive to UV and X-rays, ultrasonic vibrations, vibrations, react to changes in the acid-base state of the medium, temperature conditions.
The source and reservoir of mycoplasma respiratory infection is a person. Patients secrete the pathogen about 7-10 days after the onset of the disease, in some cases this period is prolonged. Carriage without clinical manifestations outside the epidemic focus is practically not found, but may occur transiently in persons who have long and close contact with the patient. Pneumonic mycoplasma is transmitted by means of an aerosol mechanism by airborne droplets and airborne dust, in some cases, a contact-household transmission path can be realized (through contaminated hands, household items).
The natural susceptibility of a person to mycoplasma infection is moderate, people suffering from immunodeficiency conditions caused by various kinds of severe systemic diseases, patients with Down syndrome, sickle cell anemia are more often affected. There is a genetic tendency to the development of mycoplasma respiratory infection. Postinfectious immunity is persistent, the duration can reach 5-11 years. When transferring a latent form of infection, the intensity of immunity is lower.
Pneumonic mycoplasmas have an affinity for epithelial cells lining the mucous membranes of the entire respiratory system, which allows the microorganism to infect any of its departments, causing an infiltrative inflammatory process. The production of a superoxidant by mycoplasma contributes to the death of epithelial cells of the respiratory tract, which causes inflammation both in the bronchi and in adjacent tissues. When the process spreads, the alveoli are affected, their walls are compacted at the same time.
The dissemination of mycoplasma causes inflammation of other organs and systems: joints (arthritis), meningitis (meningitis), can cause hemolysis, skin rashes. Most often, mycoplasma respiratory infection occurs in the form of pneumonia or bronchitis, laryngitis. It can manifest as ARVI, or complicate the course of any viral respiratory infection.
The incubation period of mycoplasma infection can be from several days to a month. In persons with immunodeficiency syndrome, it may manifest clinically after a long time of latent carrier of the pathogen. Respiratory mycoplasmosis often occurs in the form of various diseases of the upper respiratory tract (rhinopharyngitis, laryngopharyngitis, tracheitis, bronchitis), showing their characteristic clinical picture. The phenomena of general intoxication and temperature reaction are usually moderate, severe toxicosis and fever mainly develop in children.
With mycoplasma lesions of the upper respiratory tract, there is a dry painful cough, sore throat, rhinorrhea. Examination may reveal conjunctivitis, injection of sclera, moderate enlargement of lymph nodes: submandibular, cervical. The mucous membrane of the pharynx, tonsils, palatine arches are hyperemic, sometimes there is granularity. With auscultation of the lungs, breathing is hard, dry wheezing.
Most often, the disease is short-lived, the clinical symptoms subside after a week, sometimes it drags on for up to two weeks. In most cases, mycoplasma respiratory infection proceeds according to the type of pneumonia, which can begin both acutely, with specific symptoms of lung damage, and against the background of an ARVI clinic a few days after the appearance of catarrhal symptoms.
Mycoplasma pneumonia is characterized by intoxication (headache, chills, muscle and joint pain), fever reaching 39 degrees. The cough progresses from dry to wet, with the separation of scanty, viscous sputum of a transparent or whitish color, later with purulent inclusions. For mycoplasma pneumonia, breathing difficulties, cardiovascular disorders are not characteristic, cyanosis is not noted.
Sometimes intoxication can be accompanied by nausea, vomiting and diarrhea. The skin of patients is pale, the sclera is injected, listening to the lungs may not reveal violations at all, or detect hard breathing and localized dry or small-bubbly wheezing. The result of mycoplasma pneumonia can be bronchiectasis, deforming bronchitis, pneumosclerosis.
Mycoplasma respiratory infection can be complicated by exudative pleurisy, inflammation of the heart muscle (myocarditis), and meninges.
The causative agent of mycoplasma respiratory infection is isolated from sputum, blood, nasopharyngeal smear, after which a bacteriological study is carried out. Serological methods (detection of antibodies to the pathogen) include RNGA, RSCA, PH, ELISA. A general blood test shows lymphocytosis with a normal number of white blood cells or a moderate increase in their concentration.
An important diagnostic method for detecting pneumonia is lung radiography. At the same time, there are zones of infiltrative inflammation in the lungs, both of the lung segments and interstitial tissue. Radiological signs of pneumonia may persist for some time after clinical recovery. Patients with respiratory mycoplasmosis need to consult an otolaryngologist and a pulmonologist.
Etiotropic therapy of mycoplasma respiratory infection consists in the appointment of antibiotics: erythromycin, azithromycin, clarithromycin. The drugs are prescribed in a 10-14-day course in medium therapeutic dosages. If it is impossible to use the above funds, doxycycline can be prescribed. If the infection is limited to the upper respiratory tract, you can not resort to antibiotic therapy, limiting yourself to symptomatic means: expectorants, vasoconstrictors of topical use for rhinitis, disinfectants for gargling, physiotherapy techniques.
A good effect in mycoplasmic laryngopharyngitis and rhinopharyngitis is given by the use of local UV irradiation, inhalations with phytocompositions, bactericides. Pneumonia, as well as complicated, severe forms of mycoplasma infection are treated in a hospital. Polymorphic erythema, myelitis, encephalitis are indications for the appointment of drugs of the corticosteroid hormone group.
Prognosis and prevention
As a rule, the prognosis is favorable, especially in cases of mycoplasma infection of the type of ARVI. Pneumonia can leave behind areas of lung tissue sclerosis, bronchiectasis. The prognosis may noticeably worsen with the development of severe complications, life-threatening conditions.
The general prevention of mycoplasma respiratory infection corresponds to that of other respiratory diseases, implies the implementation of quarantine measures in the focus of infection, isolation of patients at home or in a hospital until the clinic disappears, compliance with sanitary and hygienic standards in medical institutions and collectives. Personal prevention involves avoiding close contact with sick people, the use of personal protective equipment (gauze masks to protect the respiratory tract), personal hygiene. There are no specific preventive measures for this disease.