Leptospirosis pneumonia
Introduction
Introduction to leptospirosis Leptospirosis is an acute infectious disease caused by various types of pathogenic Leptospira, which is in contact with infected wild animals and livestock. Leptospira enters the human body through exposed skin and is infected. I am sick. Rats and pigs are the main source of infection, and their clinical manifestations vary. Lighter like a cold, severe people have obvious liver, kidney, central nervous system damage, lung bleeding, and even death. basic knowledge The proportion of illness: 0.039% Susceptible people: no specific population Mode of transmission: plague spread Complications: iridocyclitis meningitis
Cause
Cause of leptospirosis pneumonia
Causes:
The hook-end spiral has a slender filament shape, a cylindrical shape, 12 to 18 spirals, hooks at both ends, and a length of 6 to 20 m. It is an active rotary motion with strong penetrating power and a negative Gram stain. Under the dark field microscope, it is easy to see the bright moving spiral. Under the electron microscope, the structure is mainly the outer membrane, the flagella (axial filament) and the cylindrical protoplast (bacteria), the aerobic and nutrient of the leptospira. The requirements are not high, and it grows well in the commonly used Kodak medium. Leptospira is extremely sensitive to dryness and general disinfectants and can be quickly killed. By 1986, 23 serogroups and 200 serotypes have been found worldwide. There are 19 groups of 74 types known in China, and the types of Leptospira are different. The virulence and pathogenicity of humans are different. Some Leptospira have hemolysin or other toxins. Various toxic leptospira enter the body through the damaged skin (or normal skin) or the nose, eyes, mouth and gastrointestinal mucosa. The pathogen penetrates extremely strongly and can quickly enter the blood circulation through the blood vessel wall or lymphatic vessels. It multiplies in the blood and invades various organs and tissues. It produces bacteremia during the incubation period. The bacteremia lasts for about 1 week and causes toxemia, causing systemic capillaries, lungs, liver, kidney, heart, central nervous system. And other organ damage.
Pathogenesis:
The pathogenesis of this disease is based on the systemic capillary damage caused by Leptospira toxin, which leads to different dysfunction of organ level. After the pathogen invades the body, a series of non-specific immune reactions appear, and the peripheral blood neutrophils increase. Mild inflammatory reaction occurs, followed by lymphocyte and plasma cell proliferation, specific antibodies appear, pathogens grow in organs, tissues, multiply, lyse, and the body develops a specific immune response, resulting in a series of damage reactions.
The pathological changes of leptospirosis are characterized by the severity of organ dysfunction and slight inconsistencies in histomorphological changes, including cases with severe clinical symptoms. This mild structural change is easily restored, and the lung is a common lesion of Leptospira. Site, common lesions, pulmonary hemorrhage, tracheal or bronchial mucosal hemorrhage, bronchial lumen and alveoli filled with red blood cells, a few alveoli still contain gas or occasionally a small amount of serous exudation, but no pulmonary edema, although there is bleeding in the alveoli, alveolar wall structure, The microstructural changes of the cytoplasmic cells are mild, and a few epithelial cells and endothelial cells have swelling or serosal rupture.
Prevention
Leptospira pneumonia prevention
Manage infectious sources, including rodent control, manage quarantine of livestock and animal hosts, timely discover and isolate patients, cut off infection routes, strengthen personal protection, and use multivalent vaccines to vaccinate susceptible people and workers exposed to water. For laboratories, epidemiological workers, and laborers in newly-occupied areas, suspected and infected people are asymptomatic, and intramuscular injection of penicillin G 800,000 to 2 million U/d for 2 to 3 consecutive days as a preventive medication.
Complication
Leptospirosis pneumonia complications Complications, iridocyclitis, meningitis
Complications are diverse, with the most prominent manifestations of the eye (uvelitis, iridocyclitis) and the brain (aseptic meningitis, occlusive cerebral arteritis), occurring in the late stage (immune response).
Symptom
Leptospirosis pneumonia symptoms common symptoms pale pale weakness unable to breathe irregular confusion blurred respiratory failure chills irritability convulsions breathing difficulties suffocation
The incubation period is 2 to 28 days, generally 7 to 12 days. Due to the immune level of the infected person and the infected strain, the clinical manifestations are complex and diverse.
1. Early (infectious toxemia) Within 3 days after onset, the main manifestations are sudden chills, fever, body temperature up to 39 ° C, mostly relaxation heat type, may be associated with headache, weakness, conjunctival hyperemia or hemorrhage, gastrocnemius Pain and tenderness can occur on the first day, and lymphadenopathy appears on the second day, with more inguinal and axillary fossa.
2. Organ damage period
3 to 10 days after the disease, according to the symptoms are divided into different clinical types.
(1) Influenza typhoid type: for the continuation of early symptoms, no obvious or serious organ damage and insufficiency.
(2) Hemorrhagic type of jaundice: It is the outer ear disease (Weil's disease), which is rare in China.
(3) meningoencephalitis type: meningeal irritation occurs in a few days after the onset, severe convulsions, coma, cerebral palsy, respiratory failure and various neurological damage.
(4) Pulmonary hemorrhage type: On the basis of early infection with toxic syndrome, hemoptysis, but no obvious pulmonary voice and respiratory dysfunction, called pulmonary hemorrhage common type, if there is infection and sepsis reaction, there is progress Difficulty breathing, hypoxia and asphyxia, rapid development of voice and X-ray showed diffuse bleeding in both lungs, called diffuse hemorrhagic lung type, this type develops rapidly, and the disease progresses in three phases.
1 aura: the patient's face is pale, irritability is gradually aggravated, breathing, heart rate is progressively increased, the lungs are scattered, gradually increasing dry, wet voice, may have blood stasis or hemoptysis.
2 bleeding period: if the treatment is not treated in time, the face is extremely pale, the lips are cyanotic, irritated, the respiratory heart rate is significantly accelerated, the first heart sound is weakened or the galloping, the lungs are covered with wet voice, most of them are different. The degree of hemoptysis.
3 dying period: If the condition is not controlled, the condition can be rapidly intensified in a short period of time (1 to 3 days). The performance is extremely irritating, ambiguous, even coma, throat snoring, extreme cyanosis, big mouth blood from the mouth, nasal surge Out (foamy), suffocation can occur, heart rate slows down, breathing is irregular or even stopped. The above evolution process is as short as several hours, and the length is 12 to 24 hours. The pathogenesis of the disease may be due to the body's pathogen and its toxic substances. The results of hypersensitivity reaction, the reasons: A. rapid onset, fierce, rapid recovery, lung lesions disappear quickly, no rupture of blood vessels, major bleeding is through three processes of congestion, congestion and hemorrhage; B. hormone therapy has special effects; C. Coagulation function is normal, no DIC manifestations.
3. Late
After 7 to 14 days of onset, most of the patients recovered quickly; in some cases, after early symptoms of poisoning, there was no obvious organ damage in the middle stage, that is, into the later stage, which was a late complication.
Examine
Examination of leptospirosis pneumonia
1. Peripheral blood: normal or slightly elevated white blood cell count and neutrophil count, increased transaminase and bilirubin in the blood.
2. Pathogen examination: Indirect fluorescent antibody staining of leptospirosis is directly searched by black-body fluorescence microscopy. Leptospira can be isolated from blood or cerebrospinal fluid within 10 days of onset, and pathogens can be detected in urine in the second week. Direct microscopic examination by fluorescent antibody staining and toluene blue staining, the positive rate is up to 50%, which is helpful for early diagnosis. The patient's blood or other body fluids are inoculated into the animal, and the pathogen is isolated and can be diagnosed.
3. Serological test: coagulation test, enzyme-linked immunosorbent assay to determine the specificity and sensitivity of specific antibodies, lectin generally appears 7-8 days after the disease, with a 1:400 titer positive, It can last for several months to several years, and the double serum titer is more than 4 times positive at intervals of 2 weeks. In recent years, leptospirosis can be diagnosed early by PCR.
X-ray manifestations of mild cases have blurred reticular shadows of the lungs or thickened lung texture, extensive lesions, moderate lungs with small dots or small snowflake shadows, low density, blurred borders, may be partially fused into 2cm The size of the shadow.
Diagnosis
Diagnosis and diagnosis of leptospira pneumonia
The clinical manifestations of this disease are complex, so early diagnosis is difficult, easy to misdiagnosis, missed diagnosis, combined with epidemiological characteristics, early clinical symptoms and pathogenic and serological examinations, and identified with other diseases. Pulmonary hemorrhage should be differentiated from tuberculosis, bronchiectasis, and tumors.
