Acute pneumonia Acute pneumonia - an acute inflammatory lung disease infectious nature with a primary lesion of respiratory and binding departments (alveoli and terminal bronchioles). Acute pneumonia is often independent disease - primary pneumonia, but more often as a complication of other pathological processes (diseases of the cardiovascular system, cancer, infectious diseases, injuries, bronchopulmonary disease, chronic bronchitis, asthma and others.) - Secondary pneumonia. The classification provides for the separation of pneumonia: - Etiology: bacterial (indicating the originator) viral mycoplasma and rickettsial, allergic due to physical and chemical factors, mixed, unknown etiology; - Pathogenesis: primary, secondary; - Morphological characteristics: lobar (lobar, fibrinous), alopecia (lobular, pneumonia); - The flow: ostrotekuschaya, protracted. Pneumonia is considered as prolonged if the normalization of clinical and radiological parameters is delayed for more than 4 weeks. The reasons for the prolonged course of pneumonia are different. The most common of them: - Started late and (or) improper treatment, which may be due to late referral of the patient medical care, incorrect diagnosis, intolerance to drugs, early cessation of antibiotic therapy, the insufficient use of the entire arsenal of therapeutic measures (including non-drug methods of treatment); - The presence of chronic respiratory diseases (particularly obstructive); - Chronic diseases of other organs and systems; - Various chronic intoxication (including manufacturing). Etiology. To date, a large number of known pathogens of pneumonia bacteria, viruses, rickettsiae, fungi, mycoplasma, legionella, chlamydia, protozoa. Clinical symptoms of the disease, the nature of morphological changes in the lungs, characteristics of the disease, its complications are largely determined by the property name of the pathogen. Therefore, it is important etiologic diagnosis of pneumonia. The main pathogens of acute pneumonia are different types of pneumococci (80-90% of acute pneumonia); other most frequent bacterial agents: staphylococci (0.4-5%), Klebsiella pneumoniae (2.1%), Haemophilus influenzae (Afanasyev-Pfeiffer), streptococci (1%). Pneumococci, Klebsiella (Friedlander bacillus), Haemophilus influenzae, Escherichia coli (E. coli) do not form exotoxins, which explains the general morphological manifestations of pneumonia caused by them. Streptococci and Staphylococci secrete an exotoxin which defines necrotic lung tissue reaction. Pneumonia often contribute to influenza viruses A and B, parainfluenza viruses, rhinoviruses, adenoviruses. Pure viral pneumonia are very rare, more common viral and bacterial pneumonia. The role of viruses is reduced to decreased immunity, violation of the nervous regulation of bronchial tone and the microcirculation and primary lesion of the bronchial or alveolar epithelium, which facilitates the penetration of the bacterial flora in the lung tissue. Thus, a viral infection contributes to bacterial infection of the lungs, imposing its mark on the course of pneumonia.
Pathogenesis. Development of pneumonia is directly dependent on the state of the microorganism (primarily its immunological reactivity) and corrosive properties of the microbial pathogen.
From this point of lobar pneumonia is seen as the result of hyperergic reaction and focal pneumonia — as a manifestation of the standard-setting or gipoergicheskih reactions of host to the infectious agent. There is another point of view — lobar pneumonia is caused by a pathogenic strains of pneumococci.
Microorganisms can enter the lungs in different ways bronchogenic, hematogenous and lymphatic. Hematogenous flow occurs in sepsis and obscheinfektsionnyh diseases and lymphogenous — in wounds of the chest. But the main route of infection — bronchogenic (inhalation and aspiration). Naturally, when this value is large airway. Respiratory protective mechanisms include mucociliary apparatus, phagocytic activity of neutrophils, a specific immune response (T, B lymphocytes, immunoglobulins, are A and G), biologically active substances, alveolar macrophages, surfactant and others. Violation of them leads to obstruction of the bronchial tree and contributes to the development of infection in respiratory departments. Decrease in the activity of protective factors of the respiratory system promotes smoking and inhalation of toxic or irritating substances, hemodynamic instability in cardiovascular diseases, chronic wasting disease (alcoholism, diabetes, and others.). Contributing to the development of acute pneumonia factors may be hypothermia, physical and mental strain.
When lobar pneumonia causative agent directly into the alveoli, giving them a dramatic toxic effect. As a result, local irritation develops serous inflammatory edema with increased growth of microorganisms, which are located on the periphery of edema. The process spreads by spreading edema fluid from the affected neighboring alveoli mezhalveolyarnyh pores Kona. A characteristic is the speed of education effusion, large content of fibrin, which greatly complicates the phagocytosis of bacteria by neutrophils and provides massive destruction of lung tissue (at least — a segment often — an entire lobe of the lung). For lobar pneumonia is characterized by a small lesion of the bronchi that are passable.
When focal pneumonia in the area of inflammation under the influence of microbial exotoxin is a rapid formation of necrosis and inflammation restriction site from the surrounding tissue. In most cases, the initial inflammatory process develops in the bronchi. Foci are small in size, occupying acinus or lobule, but sometimes coalesce to form larger lesions, and can capture a whole lot.
Mycoplasma and viral pneumonia characterized predominantly interstitial changes, when there was swelling and infiltrative proliferative changes in mezhalveolyarnyh and mezhlobulyarnyh partitions, peribronchial and perivasku-polar tissue. These changes can hardly be attributed to the term «pneumonia», as they are not in the process of lung respiratory department.
Clinic. The clinical picture of acute pneumonia is composed of the common symptoms that do not depend on the etiological structure of disease, and clinical manifestations of determining the nature of the pathogen.