Escherichia coli pneumonia
Introduction
Introduction to Escherichia coli pneumonia Escherichia coli (Escherichia coi), also known as Escherichia coli, has increased significantly in recent years. It is the second most common pathogen in the community-derived Gram-negative bacilli pneumonia after Klebsiella pneumoniae, accounting for Gram-negative bacillus pneumonia. 12% to 45%, accounting for 2.0% to 3.3% of all pneumonia pathogens. It is one of the main pathogens of acquired pneumonia in hospitals. The incidence rate is 4.2 to 9.0/10,000, accounting for 9.0 of Gram-negative bacilli pneumonia. %15.0%, the mortality rate of the disease in the 1960s was as high as 60%, and it dropped significantly after the 1980s. It was reported to be 29%, mainly in elderly debilitated patients, all kinds of chronic basic diseases, critically ill patients, trachea Intubation, long-term treatment with corticosteroids and other immunosuppressive agents, long-term use of antibiotics and dysbacteriosis, and various immunoglobulin-deficient patients, etc., are susceptible to this disease. basic knowledge The proportion of illness: 0.042% Susceptible people: no specific people Mode of infection: non-infectious Complications: lung abscess pleural effusion
Cause
Escherichia coli pneumonia
Infection (35%):
Escherichia coli was discovered in 1885 by German scientist Es-cherich, belonging to the family Enterobacteriaceae, Escherichia, Gram-negative, facultative anaerobic, with a cell size of (1.0 to 1.5) m × (2.0 to 6.0) Mm, no capsule, most strains have flagella, 4-6, are flagella, do not spore, can decompose glucose and other sugars, so that fermentation produces acid and gas, nitrate reduction test positive, oxidase negative It produces sputum, does not use citric acid, has low nutrient requirements, and grows well on common medium. The optimum growth temperature is 37 ° C, and it can grow at 42-44 ° C. This bacterium is a normal intestinal flora. And animal feces are abundant in nature, widely distributed in nature, containing plasmids encoding antibiotic resistance, colon toxin, enterotoxin, pili, etc., with O, H, K antigens on the surface, and the inhibition of drugs and other flora has been found. After the 1980s, the proportion of extended-spectrum -lactamases (ESBLs) produced by Escherichia coli increased rapidly. The rate of ESBLs production in foreign countries was 2.2% to 28%, and that in China was 5% to 32.4%.
Reduced immune defense function (30%):
Escherichia coli is a conditional pathogen, the cause of which is the decline of the body's immune defense function, inhalation of oropharyngeal colonization or infection by abdominal organs such as the gastrointestinal tract and genitourinary tract, through blood circulation, etc., mainly in the senile debilitation Patients, all kinds of chronic basic diseases, critically ill patients, tracheal intubation, long-term treatment with corticosteroids and other immunosuppressive drugs, long-term use of antibiotics and dysbacteriosis, and various immunoglobulin-deficient patients, etc. For the susceptible population of the disease, in the general hospitals such as teaching hospitals, the spread of Escherichia coli containing multi-drug resistance genes carried in specimens such as patient feces, urine and oropharyngeal secretions is difficult for treatment. .
Pathology (25%):
The pathology of Escherichia coli pneumonia is similar to that of other Gram-negative bacteria pneumonia. It mainly presents bronchial pneumonia changes in the lower lobe of the lung. It is more common in both sides of the disease. Patients with a course of more than 6 days often have small abscesses of the lungs, pleural effusion and even empyema. Change, inflammation involving tracheal-bronchial mucosa is less, probably because most Escherichia coli pneumonia is caused by blood-borne pathways, there are serous and moderate mononuclear cells in the alveoli, and the red blood cell exudation is more common in the early stage of the disease. Neutrophils, macrophages, may have thickened alveolar wall, visible necrotic lesions, some cases may be associated with Escherichia coli caused by cholecystitis, pyelonephritis or meningitis.
Prevention
Escherichia coli pneumonia prevention
In addition to improving the patient's resistance, in the hospital environment, the patient should be properly isolated, the patient's feces should be disinfected, and the disinfection and management of the toilet, faucet, water cup, etc. should be strengthened, and the medical staff should be strictly sterile. The use of implantable devices should be strictly operated.
Complication
Escherichia coli pneumonia complications Complications, lung abscess, pleural effusion
The main complications are: lung abscess, pleural effusion or empyema, shock, cardiopulmonary insufficiency and so on.
Symptom
Escherichia coli pneumonia symptoms common symptoms diarrhea dyspnea abdominal pain nausea chills
The clinical manifestations of Escherichia coli pneumonia are similar to those of general acute pneumonia. They can be characterized by chills, fever, cough, cough, chest pain, cyanosis and difficulty in breathing. They are often sticky or purulent, and may have stench. Some cases are accompanied by Gastrointestinal symptoms such as nausea, vomiting, abdominal pain, diarrhea, severe cases may have disturbances such as lethargy and peripheral circulatory disorders, lung signs may have bilateral lower respiratory tract sounds and wet snoring, lung consolidation signs Uncommon, 40% of patients may be associated with empyema and visible signs, mostly on the side of the lesion.
Examine
Examination of Escherichia coli pneumonia
Peripheral blood leukocytes and neutrophils, karyotype left shift, sputum, pleural effusion, blood and even urine and other specimens can be cultured to isolate Escherichia coli, pleural fluid examination can be serous exudative or purulent.
Ordinary fluoroscopy showed that the X-ray showed diffuse patchy infiltrative shadows. It was dominated by two lower lungs, with occasional signs of consolidation. It was often found that medium-sized abscess formation and pleural effusion were common.
Diagnosis
Diagnosis and identification of Escherichia coli pneumonia
Diagnosis: There are many kinds of Gram-negative bacilli that can cause pneumonia, clinical manifestations are similar, and the auxiliary examination lacks specificity. Therefore, diagnosis of Escherichia coli pneumonia requires clinical combination of pathogens, symptoms of pneumonia, original chronic diseases, long-term use of antibiotics. Or use the history of immunosuppressants, accompanied by gastrointestinal symptoms, and even psychiatric symptoms, the disease progresses quickly and can be complicated with empyema, should consider the disease, sputum smear test can distinguish whether the pathogen is Gram-negative bacilli, sputum culture positive should be excluded Contamination of oropharyngeal colonization bacteria, so the first qualified specimen should be taken, that is, the proportion of leukocytes and epithelial cells in the sputum smear is more than 2.5, and the qualified sputum culture is more than twice and separated into Escherichia coli and is the dominant bacteria, or Quantitative culture of the isolated bacteria concentration 10 CFU / ml, or the use of TTA, PSB, BAL, LA and other anti-pollution lower respiratory tract specimen sampling techniques collected from the specimens isolated Escherichia coli can confirm the disease, such as pleural fluid and blood specimens cultured Escherichia coli can also establish a diagnosis, DNA probes or PCR methods can be used when conditions permit, if pneumonia secondary to urinary tract infection, and urinary tract When both sputum cultures and Escherichia coli are positive, they also have diagnostic value.
Differential diagnosis: The differential diagnosis of this disease and other bacterial pneumonia depends mainly on the establishment of pathogens, and sometimes it is difficult to identify clinical manifestations alone.
