Mycoplasma pneumonia test

To date, there are no clinical, epidemiological or laboratory symptoms that would allow early detection of Mycoplasma pneumoniae lung damage. Diagnosis is performed only after the appearance of a symptomatic pathology. There are certain signs that make it possible to suspect atypical pneumonia:

• A sharp rise in body temperature from the first for the disease from 38 ° C.
• Productive cough with separation of viscous purulent sputum.
• Difficulty breathing, shortness of breath and blueing of the nasolabial triangle.
• An increase in the number of leukocytes in the blood.

Diagnosis of mycoplasma pneumonia consists of the following stages:

1. Collection of anamnesis and analysis of patient complaints - the doctor learns how long the first painful symptoms have appeared, whether there are chronic diseases and other features of the onset and course of the disease.
2. Visual inspection and percussion - the doctor examines the patient's chest. If there is an intercostal occlusion gap or during breathing, one side lags behind the other, this indicates pneumonia. Also performed percussion, that is, tapping the chest with your fingers. On the basis of the received sound, the doctor draws conclusions about the state of the lungs.
3. Auscultation - with the help of a stethophonendoscope, the lungs are listened. Normally, sound should be clean, and breathing calm and measured. If breathing is difficult, there is gurgling or wheezing, it is a sign of accumulation of exudate that interferes with normal lung function.
4. Laboratory diagnostics - the patient needs to pass a general analysis of blood and urine, sputum analysis, PCR, ELISA.
5. Instrumental diagnostics is a complex of studies for establishing the exact cause of a morbid condition. Patients are assigned X-ray diagnostics, tomography, ultrasound, bronchoscopy, CT and other examinations.

Analyzes

Laboratory diagnostics of pulmonary mycoplasmosis consists of a complex of such analyzes:

1. General blood analysis

• Erythrocytes are above normal.
• Leukocytes are significantly elevated in the bacterial form of the disease.
• Leukocyte formula - neutrophils predominate with toxic granularity, shift the formula to the left.
• Lymphocytes - decreased because of the increase in neutrophils.
• ESR is above normal.
• Platelets are within normal limits.

The heavier the patient's condition, the more pronounced the changes in blood.

2. Blood chemistry

• The total protein is normal.
• C-reactive protein - increased.
• LDH and fibrinogen - increased.
• Alpha and gamma globulins are increased.

3. Analyzed sputum is an increased number of neutrophils, fibrin, elastic fibers, erythrocytes.
4. Analysis of blood and sputum for immunoglobulins IgM, G to mycoplasmas.
5. Blood test for bacterial DNA.
6. Analysis of the gas composition of blood.

The doctor is deciphering the received analyzes. According to their results, the doctor makes a plan of treatment or appoints additional studies.

[1], [2], [3], [4], [5]

PCR

The experimental diagnostic method of molecular biology for determining the state of DNA fragments in a biological material is a polymerase chain reaction. PCR for suspected mycoplasma pneumonia is a study of blood, sputum, pleural fluid and other types of biomaterial for pathogenic microorganisms.

Advantages of PCR:

• Increased percentage of detectable DNA pathogens in clinical trials in comparison with standard diagnostic microbiological methods.
• High sensitivity when suspected of generalized processes in the body.
• Identification of difficultly cultivated microorganisms and uncultivated forms of bacteria in persistent infections.

Detection of pathogens in the biomaterial is not always of diagnostic significance. This is due to the fact that many microorganisms normally live in the respiratory tract, but under certain conditions realize their pathogenic potential, causing infectious processes.

IFA

The laboratory immunological method for the qualitative / quantitative determination of viruses and other pathogens is an ELISA. Immunoenzymatic analysis is carried out in such cases:

• Search for specific antibodies to infectious pathologies.
• Determination of antigens to various diseases.
• Research of hormonal status.
• Examination for autoimmune diseases and oncomarkers.

Advantages of ELISA are high sensitivity and specificity, the ability to determine the disease and trace the dynamics of the pathological process. The main drawback of the method is the detection of antibodies, that is, the immune response, and not the pathogen itself.

To detect Mycoplasma pneumoniae for the ELISA, blood sampling is performed. The analysis is confirmed if IgM, G immunoglobulins are detected in the blood. If the growth of antibody titer is increased by 3-4 or more times, the enzyme immunoassay confirms atypical pneumonia.

Antibodies to mycoplasma pneumonia igG

Specific antibodies produced by the immune system in response to infection by various pathogens are immunoglobulins. Antibodies to mycoplasma pneumonia igg are serological markers, indicating a pathological process in the body.

Mycoplasma pneumoniae occupies an intermediate position between bacteria, protozoa and viruses. It causes damage to the respiratory system and accounts for about 20% of all cases of community-acquired pneumonia. After infection, the immune system begins to actively produce immunoglobulins of class A, M and G.

IgG in relation to mycoplasmal infection manifests itself in 2-4 weeks and continues to be produced for a long period of time, usually more than a year. The blood test for these immunoglobulins is part of a complex of mandatory laboratory tests for suspected atypical pneumonia. To reduce the risk of diagnostic errors, a simultaneous analysis for IgM and IgG is shown.

[6]

Antibodies to mycoplasma pneumonia igM

To confirm acute mycoplasma lesion of the respiratory system, patients are assigned an enzyme immunoassay. Antibodies to mycoplasma pneumonia IgM allow differentiating atypical inflammation from other pathologies of the respiratory tract, for example the infectious process caused by streptococci or staphylococci.

The reason for conducting a laboratory test is the following symptoms:

• Unproductive cough for a long period of time.
• Expressed pain in the throat and chest.
• Muscle pain.
• Deterioration of general well-being.

The coefficient of positivity, indicating infection, is the values: 0-0.84. A negative result is possible not only in the absence of disease, but also in chronic mycoplasmal infection, early infection, when the body has not yet developed an immune response. It should also be noted that with repeated initiation IgM is usually not released.

[7], [8], [9], [10]

Cold antibodies with mycoplasma pneumonia

Antibodies that cause erythrocyte aggregation when exposed to low temperatures are cold antibodies. With Mycoplasma pneumonia, they most often belong to the class of IgM. Normally, they can be found in healthy people, but significantly increase in 7-10 days after the onset of the disease. Cold exposure causes acute transient hemolytic anemia. A steady increase in the titer of agglutinins leads to the development of a chronic form of pathology.

There are several types of cold agglutinins:

• The disease is caused by a primary intravascular hemodialysis with monoclonal antibodies to the erythrocyte I-antigen. In this case, cold antibodies are formed with lymphoproliferative disorders.
• The painful condition is caused by secondary intravascular hemolysis. It is characterized by polyclonal antibodies in low titre and active in a narrow temperature range. It manifests itself in various infections. For example, with mycoplasmal pneumonia, cold agglutinins appear to the erythrocyte I-antigen.

Cold antibodies in atypical pneumonia can act as a mixture of different immunoglobulins. Activation of agglutinins begins already at 37 ° C and causes such pathological reactions: acrocyanosis and hemolysis due to activation of complement.

[11], [12], [13], [14],

Instrumental diagnostics

To determine the localization of the inflammatory focus in the lungs, its size and other features, instrumental diagnostics is shown. The research complex consists of the following procedures:

• Radiography.
• Fibrobronoscopy.
• CT.
• Function of external respiration.
• Electrocardiography.

The main diagnostic method is radiography. It allows you to identify foci of inflammation, which in the picture seem darker than the rest of the lung. There is also a change in the pulmonary pattern and the proliferation of connective tissue. With pneumonia, it is possible to change pulmonary roots, pleural lesions and even the presence of an abscess in the organ. Radiography is performed in two projections - direct and lateral.

Tomography gives the same result as the X-ray, so it is rarely performed with suspected atypical pneumonia. Also, ultrasonic diagnostics is rarely performed, since it reveals only exudates in the lungs, which is also visible on the X-ray. As for bronchoscopy, it is necessary to obtain more accurate results of the study.

Differential diagnostics

For successful treatment of any disease requires a comprehensive examination. Differential diagnosis of atypical pneumonia is aimed at eliminating pathologies with similar symptoms. This allows you to establish an accurate diagnosis and prescribe therapy.

Differentiation is carried out in several stages:

1. Collection of primary data and the formation of a list of possible diseases.
2. Study of symptoms, changes in the dynamics of well-being and other factors of the disease.
3. Comparative analysis of the data obtained, evaluation of similar and different values.
4. Identification of external symptoms that are not related to suspected pathology.
5. Exclusion of diseases, the clinical signs of which are not included in the overall picture.
6. Setting the final diagnosis and drawing up a treatment regimen.

Collected and analyzed in the process of diagnosis, the data provide a reliable picture of the disease state. Differentiation of atypical pneumonia is carried out with the most common harmful microorganisms:

• Mycoplasma - acute onset, catarrh of upper respiratory tract, cough with poorly separated sputum. As a rule, it develops in patients of a young age.
• Pneumococci - acute onset of the disease, severe fever, severe course, but a good response to antibacterial drugs of the penicillin series.
• Staphylococci - acute onset and severe course, limited infiltrates, resistance to penicillins.
• Haemophilus influenzae is a severe course, extensive infiltrates, thick sputum with impurities of blood, abscess formation. Most often occurs in patients with chronic bronchopulmonary pathologies and alcoholism.
• Legionellosis - severe course, diarrhea and hepatic dysfunction, neurological disorders. The disease affects people who are in an air-conditioned room for a long time
• Aspiration - putrefaction, multiple and discharge foci of inflammation, reflex cough and increased salivation.
• Pneumocysts - increasing shortness of breath with frequent coughing attacks. Severe symptoms with mild radiographic signs.
• Fungi - rapid development of fever, cough with poor sputum, expressed fever, pain in the chest.

Most pathogens have a similar symptom complex, so much attention is paid to bacterial culture. Atypical pneumonia is differentiated from other diseases. During the examination, the physician determines extrapulmonary pathology with signs from the respiratory organs and limits pulmonary inflammation from other possible disorders on the part of the respiratory system:

1. Tuberculosis is most often mistaken for pneumonia. It flows with a dry cough, subfebrile body temperature and pale skin. If positive tuberculin tests are detected, the diagnosis becomes more complicated. The main differences from pneumonia: heterogeneous and condensed shadows, areas of enlightenment are similar to contaminated foci. In sputum there is a massive distribution of mycobacteria. Leukocytes are increased in the blood.
2. Bronchitis - occurs after SARS or against their background. In the early stages is accompanied by a dry cough, which gradually turns into productive. The raised temperature keeps 2-3 days, and then remains in subfebrile limits. Infiltration is absent, the pulmonary pattern is strengthened. Very often pneumonia is diagnosed as an exacerbation of bronchitis.
3. Influenza - in the epidemiological period it is very difficult to distinguish between pulmonary inflammation and influenza damage. Special features of the clinical picture of the disease are taken into account.
4. Pleurisy is an inflammatory pathology in the respiratory system, similar to pleural changes. Flows with pain in the chest and during a cough. The main diagnostic sign of pleurisy is wheezing, that is, the sounds of friction of the pleura during breathing. Particular attention is paid to the results of biochemical analysis.
5. Atelectasis is a pulmonary pathology with tissue decay and gas exchange disturbance. On the symptomatology reminds a pneumonia: respiratory failure, otdyshka, cyanosis of integuments. The pain in the chest in this disease is caused by a violation of gas exchange. In the folded part of the body, the infection gradually develops. Atelectasis is associated with trauma, blockage and compression of the lungs, destructive tissue changes.
6. Oncological processes - the initial stages of the disease do not differ from atypical pneumonia. Differentiation is based on a comprehensive diagnostic approach with a thorough study of the signs of cancer.

In addition to the above diseases, mycoplasma pneumonia differentiates with dysfunctions of the cardiovascular system, gepostazom, rheumatoid arthritis, collagenoses, pulmonary infarction and other disorders of the body.

[15], [16], [17], [18], [19], [20], [21], [22], [23]