What Is Bacterial Pneumonia?

Bacterial pneumonia is the most common pneumonia and one of the most common infectious diseases. It mainly includes pneumonia such as Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae, Haemophilus influenzae, Pseudomonas aeruginosa, The health threat to children and the elderly is enormous.

Basic Information

Visiting department

Respiratory Medicine

Multiple groups

Children, seniors

Common locations

Lungs

Common causes

Caused by bacterial infection

Common symptoms

Cough, expectoration, purulent or bloody sputum, with or without chest pain

Causes of bacterial pneumonia

Classified by anatomy, pneumonia can be divided into lobular, lobular and interstitial. In order to facilitate treatment, they are mostly classified according to the etiology, mainly infectious and physiochemical pneumonia. Physicochemical properties include radiation, poison gas, drugs and allergies, such as allergic pneumonia. The vast majority of clinical findings are infectious pneumonia caused by bacteria, viruses, chlamydia, mycoplasma, rickettsia, fungi, and parasites, among which bacterial is the most common. The pathogens of pneumonia vary greatly depending on the host's age, concomitant diseases and immune function status, and how they are obtained. The common pathogens of community-acquired pneumonia are Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma, Streptococcus pyogenes, Legionella, virus, Chlamydia, etc. In hospital pneumonia, Pseudomonas aeruginosa and other pseudomonas Klebsiella pneumoniae, Escherichia coli, cloacae and Enterobacter aerogenes, Proteus, Methicillin-resistant Staphylococcus aureus and fungi are common. Aspiration pneumonia is mostly caused by anaerobic infection.

Clinical manifestations of bacterial pneumonia

Symptoms of bacterial pneumonia vary widely, and can vary from light to heavy, depending on the state of the pathogen and the host. Common symptoms are cough, sputum, or exacerbation of the original respiratory symptoms, with purulent or bloody sputum, with or without chest pain.

Symptoms

There are often inducements such as cold and fatigue, or basic diseases such as chronic obstructive pulmonary disease and heart failure. One-third of the patients had a history of upper respiratory infection before the illness, and most of them had an acute onset. Gram-negative bacillus pneumonia, elderly pneumonia, and hospital-acquired pneumonia onset are hidden. Fever is common, mostly persistent high fever, and the fever type after antibiotic treatment may be atypical. There are many coughs and sputum. The early stage is dry cough, and gradually there is sputum. The amount of sputum varies. The sputum is mostly purulent. The typical sputum of S. aureus pneumonia is yellow purulent or purulent sputum, Streptococcus pneumoniae pneumonia is rust-colored sputum, Klebsiella pneumoniae is brick red slimy sputum, and patina Pneumococcal pneumonia is pale green sputum. Anaerobic sputum infection is often accompanied by odor. After the antibacterial treatment, the development of the above-mentioned typical sputum performance is rare. Hemoptysis is rare. Part of the chest pain, acupuncture pain when the pleura is involved. Lower lobe pneumonia stimulates the iliac pleura, and pain can radiate to the shoulder or abdomen, which is easily misdiagnosed as acute abdomen. Systemic symptoms include headache, muscle soreness, and fatigue, and a few have gastrointestinal symptoms such as nausea, vomiting, bloating, and diarrhea. Severe patients may have neurological symptoms such as drowsiness, disturbance of consciousness, and convulsions.

2. Signs

The patient was acutely sick, breathing shallowly, and some had wing flaps. There are often varying degrees of cyanosis and tachycardia. A few can occur with shock (with blood pressure dropping below 90 / 60mmHg within 24 hours or even undetectable, with irritability, pale, cold limbs, oliguria, tachycardia, and weakened heart sounds, etc.), more common in the elderly. Streptococcus pneumoniae pneumonia is often associated with herpes simplex on the lips, and early signs of the chest can be found without abnormalities or with only a small amount of wet rales. As the disease progresses, typical signs gradually appear. Unilateral pneumonia may include weakened respiratory motion on the ipsilateral side, dull percussion sounds, reduced breath sounds, and moist rales. Signs of consolidation often suggest a bacterial infection. Pneumonia, gram-negative bacillus pneumonia, and chronic bronchitis in the elderly are secondary to pneumonia, which often affect both sides at the same time. Examination of both lower lungs and wet rales can be heard.

The total number of white blood cells and neutrophils increased. The white blood cell count of elderly frail people may not increase, but the percentage of neutrophils is still high. Significant lung inflammation but a non-increased white blood cell count often indicates a serious condition. Arterial blood oxygen pressure often shows a decrease.

Bacterial pneumonia test

Chest x-ray

The most common manifestation is a bronchopneumonia-type change, which usually does not help determine the cause of pneumonia, but certain characteristics may be helpful for diagnosis, such as consolidation of the lung lobe, formation of cavities, or a large amount of pleural effusion. Staphylococcal pneumonia can cause significant lung tissue necrosis, lung air sacs, lung abscesses, and empyema. Gram-negative bacillus pneumonia often presents as a type of lower bronchial pneumonia and is prone to form multiple small pus cavities.

2. Bacteriological examination

Sputum or pleural fluid smear test, culture of pathogenic bacteria and antibiotic sensitivity test. The same bacteria grow for two or three times in a row, and the possibility of pathogenic bacteria is high. Only one positive or multiple times for different bacteria growth, the reliability is poor. Bacteria concentrations 107 CFU / ml are pathogenic bacteria, 105-107 CFU / ml are suspicious, and <105 CFU / ml are mostly contaminating bacteria.

3. Blood test

The white blood cell count and neutrophil are generally increased, and the nucleus may be shifted to the left. The white blood cell count may not be increased in elderly or frail cases.

4. Immunological examination

Using immunofluorescence, enzyme-linked immunosorbent assay, convection immunoelectrophoresis and other methods to detect the antigen or antibody of serum pathogenic bacteria can help the diagnosis of Mycoplasma infection and Legionella infection. The polymerase chain reaction has certain significance for virus detection.

5. Other inspections

If necessary, blood gas analysis, liver, kidney function, serum electrolytes and other related tests.

Diagnosis of bacterial pneumonia

According to typical symptoms and signs, combined with chest X-ray examination, it is easy to make a preliminary diagnosis. Patients with old age, secondary to other diseases, or changes in focal pneumonia often have atypical clinical manifestations and need to be carefully identified.

Differential diagnosis of bacterial pneumonia

A few non-infectious conditions can have similar symptoms to pneumonia, such as acute respiratory distress syndrome, congestive heart failure, pulmonary embolism, chemical gas inhalation, allergic alveolitis, drug-induced pneumonia, radiation pneumonitis, connective tissue disease involving the lungs, tuberculosis , Leukemia or other malignant tumors with invasion or metastasis in the lungs, etc., should pay attention to identification, if necessary, diagnostic treatment can be used to confirm the diagnosis.

Bacterial pneumonia complications

Complications have been rare in recent years. Patients with severe infection poisoning are prone to septic shock, especially the elderly. Presented as decreased blood pressure, cold limbs, sweating, cyanosis, tachycardia, arrhythmia, and high fever, chest pain, cough and other symptoms are not prominent. Other complications include pleurisy, empyema, pericarditis, meningitis, and arthritis.

Bacterial pneumonia treatment

Antibacterial therapy is the key to determining the prognosis of bacterial pneumonia.

After 3 to 5 days of anti-infective treatment, the condition has not improved or worsened, and anti-infective drugs should be replaced. When the result of the pathogen examination is available, the sensitive drug should be selected according to the drug sensitivity test. If no etiology data are available, the possible pathogens of pneumonia should be re-examined for a new round of empirical treatment. The total course of mild to moderate pneumonia can be ended 3 to 7 days after the symptoms are controlled, such as body temperature turning normal; those with a severe condition are 1 to 2 weeks; Staphylococcus aureus pneumonia and pneumonia in immunosuppressed patients, the treatment course should be appropriately extended; inhalation For pneumonia or lung abscess, the total course of treatment should take weeks to months.

Other treatments should be selected according to the condition, such as oxygen inhalation, cough and phlegm elimination, infusion and anti-shock.

General treatment

Rest in bed, enter easily digestible protein, electrolytes, vitamin foods, pay attention to water supplement. Those with high fever are given physical cooling, and antipyretics are given if necessary.

2. Promote expectoration

Encourage patients to cough, turn over, or pat their back to promote expectoration. Give expectorants and antispasmodics, and inhale normal saline when necessary.

3. Application of antibiotics

According to the severity of the patient's disease and possible pathogen infection, the rational application of antibacterial drugs is recommended according to the guidelines.

4. Immunotherapy

Immune globulins, transfer factors, thymosin and other immune modulators can help the treatment and help.

5. Treatment of complications

Respiratory failure was given oxygen therapy and respiratory support. Patients with electrolyte disorders and liver and kidney dysfunction should be treated accordingly. Empyema should be drained or surgically treated.