Staphylococcal pneumonia

Staphylococcal pneumonia is an inflammation of the lungs, characterized by severe course, sometimes up to sepsis, frequent recurrence and the formation of foci of abscess formation in the lung tissue. Causes this type of pneumonia St.aureus.

Staphylococcus aureus causes approximately 1% out-of-hospital and 10-15% intra-hospital pneumonia.

[1], [2], [3], [4], [5], [6], [7], [8],

Risk Factors of Staphylococcal Pneumonia

The following groups of people are most prone to the development of this pneumonia:

• infants;
• people of advanced age;
• persons weakened, having suffered any serious diseases, surgical operations;
• patients suffering from cystic fibrosis;
• patients with impaired immune system function;
• injecting drug users;
• patients who have recently undergone viral pneumonia.

Symptoms of Staphylococcal Pneumonia

In general, the clinical symptomatology of staphylococcal pneumonia is similar to pneumococcal pneumonia, but there are also significant differences:

• Staphylococcal pneumonia is characterized by recurrent chills, while pneumococcal pneumonia usually shows a single chill at the onset of the disease;
• Staphylococcal pneumonia is often a manifestation of sepsis;
• the course of pneumonia is usually severe, with a high body temperature, severe intoxication and shortness of breath;
• often there are destructive changes in the lungs.

The following clinical forms of staphylococcal pneumonia are distinguished:

Staphylococcal destruction of lungs (bullous form)

This is the most common form. It is characterized by the fact that already during the first days of the disease against the background of inhomogeneous lung infiltration cavities of destruction with thin walls are formed - "staphylococcal bullae". These cavities are not an abscess, they do not have liquid contents, they quickly arise and disappear within 6-12 weeks against the background of treatment. The role of the valve mechanism in the appearance of bullae is assumed.

Unlike lung abscess above the zone of destruction, amphoric breathing is not heard, there is no "breakthrough in the bronchus" characteristic of the abscess of the symptom complex. The prognosis of this form is considered to be comparatively favorable - recovery comes, on the site of cavities of destruction, an air (residual) cyst can be preserved.

Staphylococcal infiltrate

With this variant of staphylococcal pneumonia, the condition of patients is severe, intoxication is severe, the clinical state resembles septic. Physical examination of the lungs reveals a significant blunting of percussion sound in the affected area of the lung, with auscultation, a sharp weakening of vesicular breathing, crepitus (at the beginning of the formation of the infiltrate and at its resolution), it is possible to listen to bronchial breathing.

X-ray examination reveals infiltrative darkening in a limited area of various sizes. Staphylococcal infiltrate resolves slowly, for 4-6 or more weeks, in the future, the formation of focal pneumosclerosis is possible.

Staphylococcal abscessed form

During the disease, there are 2 periods: before and after the breakthrough of the abscess into the drainage bronchus.

The first period (before the breakthrough in the bronchus) is characterized by a very severe course, fever with chills, severe intoxication, pain in the chest in the projection of the abscess, dyspnea. Radiographic examination reveals a focus of pulmonary tissue infiltration. After a breakthrough in the bronchus, the patient coughs a large amount of purulent sputum, sometimes with the presence of blood, after which the body temperature decreases, intoxication decreases. With auscultation of the lungs in the projection of the abscess, small bubbling rales, sometimes amphoric breathing, are heard. X-ray examination reveals a cavity with a horizontal level on the background of the infiltration focus, sometimes several abscesses are formed and then multiple cavities are determined.

Metastatic Staphylococcal Lung Disease

This form of staphylococcal pneumonia develops as a result of a hematogenous migration of infection into the lungs from a purulent focus and proceeds very hard. As a rule, the defeat is bilateral, the septic state develops. X-ray examination of the lungs reveals multiple foci of abscess formation (cavities with horizontal fluid levels in infiltration sites), combined with bullae.

Pulmonary-pleural form

This form of staphylococcal pneumonia is characterized by the development of infiltrative or abscessed foci in the affected lung, combined with involvement in the pathological process of the pleura and the appearance of pyopneumothorax, empyema of the pleura. The clinical symptoms of these complications are described in the relevant chapters.

The data of laboratory studies with staphylococcal pneumonia are similar to those in pneumococcal pneumonia, but in some cases the toxic granularity of leukocytes is very pronounced, there is a significant increase in the number of young and rod-shaped leukocytes.

Diagnosis of Staphylococcal Pneumonia

The diagnosis of staphylococcal pneumonia is based on the following provisions:

• presence in the clinical picture and in the radiographic examination of the lungs of the corresponding symptomatology;
• Detection of sputum smears stained according to Gram by microscopy, gram-positive staphylococci in the form of grapes;
• sowing of staphylococcus from the blood, the contents of the pleural cavity with empyema of the pleura. Staphylococcus is easily detected by seeding, false negative results are very rare;
• positive serological tests (growth of antitoxin titer, growth of agglutinins to own strain of staphylococci).

[9], [10], [11], [12], [13]

Treatment of staphylococcal pneumonia

With strains sensitive to penicillin, Staph. Aureus prescribe large doses of benzylpenicillin - up to 20,000,000 units / day and more. Usually begin with intravenous administration, at the same time part of the daily dose is injected intramuscularly, then they switch to intramuscular injection of the antibiotic. In case of penicillin intolerance, parenterally large doses of macrolides (erythromycin, spiramycin), chloramphenicol or lincosamines can be used.

In the case of isolation of penicillin-resistant strains, semi-synthetic penicillins (oxacillin) are prescribed.

The average daily dose of oxacillin is 8-10 g. Initially, parenteral administration is advisable, then it is possible to switch to oral administration. In the severe course of the disease, it is justified to combine oxacillin with aminoglycosides.

A good clinical effect is produced by cephalosporins of the first and second generations in submaximal doses (for example, cefazolin 3-4 g per day intravenously or intramuscularly).

Lincomycin or clindamycin (1.8-2.4 g per day), fusidine (1.5 g per day), parenteral macrolides at the maximum doses may be effective. They are administered intravenously, and then switched to intramuscular administration or oral administration.

With staphylococcal pneumonia caused by oxacillin-resistant Staph strains. Aureus, it is advisable intravenous administration of vancomycin (30 mg / kg per day) or teicomanin (3-6 mg / kg / day, in severe cases up to 9.5 mg / kg / day with an infusion interval of 12 hours) in combination with phosphomycin (200 mg / kg per day every 6 hours at an infusion rate of 1 g / h). In recent years, fluoroquinolones have become widely used.

You can use an antistaphylococcal drug - chlorophyllipt intravenously - 8-10 ml of 0.25% solution in 150 ml of isotonic sodium chloride solution with 5000 units of heparin 2 times a day. The course of treatment is 14-15 days.

An intravenous injection of antistaphylococcal plasma is also mandatory.