Francisella pneumonia
Introduction
Introduction to Francis Pneumonia Tularemia is a common animal-borne disease in the United States, and its pathogenic fungus, Francisellatularensis, is widely parasitic on many wild animals, livestock and birds. The cockroach or deer fly bite is the main mode of transmission. Like other plagues, T. elegans mainly affects the skin and local lymph nodes, which are characterized by focal suppurative and granulomatous inflammatory reactions throughout the body, involving the lungs. Generally caused by bacteremia or primary inhalation pathogenic bacteria, about 10% to 15% of cases of ulcerative granuloma caused by F. serrata involve the lungs. basic knowledge The proportion of illness: 0.003% Susceptible people: no special people Mode of infection: contagious Complications: bacteremia, pleural effusion
Cause
Cause of Francisella pneumonia
(1) Causes of the disease
T. calorie is a genus of the genus Francisella, which is a fragile, tiny gram-negative globular bacterium, has no motility, has no capsule in culture, but can be in the secretion of living organisms. Appears, it is difficult to grow on common medium, and grows best in medium rich in serum, sugar and cystine. Suitable growth temperature is 36-37 ° C, pH 6.8-7.2, heat-resistant, low temperature It is more tolerant and is generally considered to have endotoxin.
(two) pathogenesis
There are a variety of protein and polysaccharide antigens on the cell membrane of F. serrata. In addition, there are endotoxin similar to other Gram-negative bacteria. Pathogenic bacteria can enter the body through the skin or mucosal damage, causing local lymph nodes. Suppurative infection, occasionally causing bacteremia, bacteria spread to other organs, including the lungs, unexplained rhabdomyolysis often accompanied by bacteremia and pneumonia, bacteria entering the digestive tract can cause pharyngitis and gastrointestinal Inflammation of the tract, the inhalation of bacteria through the respiratory tract can cause primary pneumonia, manifested as multiple sites of inflammation, necrosis and granuloma formation.
Prevention
Francisella pneumonia prevention
Pay attention to self-protection when in contact with animals in the affected area, such as wearing gloves; wear protective clothing or spray insecticide to prevent contact and infection.
Complication
Francis pneumonia complications Complications bacteremia pleural effusion
Complicated bacteremia, involving the pleural effusion caused by pleural effusion.
Symptom
Francisella pneumonia symptoms common symptoms chest pain pleural effusion
Pneumonia caused by bacterial dissemination with blood flow often occurs in the first 2 to 3 weeks of the course of the disease, manifested as cough, phlegm or blood stasis, chest pain and shortness of breath, patients often accompanied by fever and localized ulcerative granuloma formation, by inhalation Caused by primary pneumonia, in addition to cough, shortness of breath, occasionally involving the pleura, causing pleural effusion.
Examine
Examination of Francisella pneumonia
, Gram staining and culture in pleural effusion are not easy to find pathogenic bacteria, but direct fluorescein-labeled antibody staining positive, double serum agglutination test is very helpful for the diagnosis of the cause, that is, acute and recovery double serum, antibody drops The degree is increased by more than 4 times. If the single serum antibody titer exceeds 1:160 during the recovery period, it is highly suspected that there is an active lesion in the body. The antigen skin test is also helpful for diagnosis, but the preparation of the antigen is not easy.
There may be no abnormalities in X-ray performance at 2 to 4 hours after the onset of fever. Later, pulmonary infiltrating lesions and hilar lymphadenopathy may occur, which may involve the pleura and cause pleural effusion. The X-ray changes of this disease are not proportional to the signs, namely diffuse bronchopneumonia. Unilateral or bilateral pleural effusion, but the signs are relatively light, and the central oval-shaped dense shadow that has been used as a characteristic feature in the past is rarely found.
Diagnosis
Diagnosis and identification of Francisella pneumonia
The diagnosis is based on the history of animal exposure in the affected area or the history of arthropod bites in the affected area. It shows fever, skin lesions and swollen lymph nodes. The possibility of Tala fever should be highly suspected, such as cough, shortness of breath, chest pain, etc. X-ray confirmed lung involvement, and the cause of diagnosis was feasible by direct fluorescein-labeled antibody staining and serum agglutination test.
Differential diagnosis
There are many diseases that are similar to Francis's pneumonia and must be identified, such as
1 non-bacterial pneumonia: parrot fever, Q fever, mycoplasma pneumonia;
2 bacterial pneumonia: plague pneumonia, tuberculosis;
3 deep fungal infections throughout the body.
