Overview
Nosocomial pneumonia, or Willebrandia pneumonia, is a disease caused by the invasion of the human body by the bacterium Pseudomonas nosocomialis. It is endemic in tropical areas such as Southeast Asia and northern Australia. It can be transmitted between humans and animals. Most lesions occur in the lungs during acute infection. The population is generally susceptible to B. anthracis-like bacteria. Associated symptoms include headache, chest pain, cough and shortness of breath. The incubation period is usually 4 to 5 days, but there are cases where the disease develops months, years, or even up to 20 years after infection. Such cases are often triggered by trauma or other diseases. According to serologic surveys, occult infection is present in 6% to 20% of the population in endemic areas. There are more males than females and it is thought to be related to occupational exposure.
Etiology
Pneumocystis carinii pneumonia is a disease caused by the invasion of the human body by Pseudomonas carinii and can be transmitted between humans and animals. The main route of transmission is direct contact with water or soil containing the causative agent and infection through broken skin. Inhalation of dust or aerosols containing pathogenic bacteria and infection via the respiratory tract; ingestion of food contaminated with pathogenic bacteria and infection via the digestive tract; and bites from blood-sucking insects (fleas, mosquitoes).
Symptoms
1. Hidden infection
Asymptomatic only high titers of specific antibodies are found in serologic tests. Positive rate of 6% to 20% in healthy adult males in endemic areas. Occasional cases of asymptomatic infection detected on routine radiographs have been reported.
2. Acute limited pyogenic infection
It is often due to bacterial infection of broken skin, localized formation of nodules, and complication of lymphangitis and affiliated lymphadenitis. Patients often have fever and generalized discomfort, and then rapidly develop acute sepsis.
3. Acute lung infection
It is the most common form of the disease. It manifests as primary or hematogenous disseminated pneumonia. Sudden onset, chills or chills, followed by fever, generalized muscle pain, headache, cough, chest pain, shortness of breath, the lungs can be heard rales, X-ray examination of the lungs, solid changes, some may occur thin-walled cavities. When the temperature drops, the cavity may persist, resembling the X-ray presentation of tuberculosis. In some patients, progressive intrapulmonary or hematogenous dissemination may occur successively, developing into sepsis.
4. Acute septicemic infection
Sudden onset, chills, high fever; small pustules on the skin of head, trunk and limbs. If combined with pneumonia, it is often accompanied by severe dyspnea, severe headache, cough and chest pain. Wet rales and pleural friction sounds appear in the lungs, and X-ray examination often shows irregular nodular shadows with a diameter of 4-10 mm throughout the lungs, followed by enlargement of the nodules and fusion to form cavities. Patients may develop arthritis or meningitis. The liver and spleen are enlarged. The prognosis is poor, the disease develops rapidly and often dies without treatment.
5. Chronic purulent infection
Some patients have secondary suppurative foci after the acute stage, such as osteomyelitis, suppurative lymphadenitis, subcutaneous abscess, lumbar muscle abscess, lung abscess, pyothorax, liver abscess, splenic abscess, and pyelonephritis, etc. These abscesses may form fistulas and fistulas, which are often associated with arthritis or meningitis. These abscesses may form fistulas, and if left unhealed for a long period of time they may become chronic, with the patient becoming progressively emaciated and debilitated.
Examination
1. Laboratory examination
(1) Blood picture: Most patients have anemia. The total number of leukocytes increases in the acute stage, and the increase of neutrophils is dominant.
(2) Bacterial culture and animal inoculation Bacterial culture of blood, sputum, cerebrospinal fluid, urine, feces, purulent exudate from localized lesions or animal inoculation can isolate Bacteroides nosocomialis, with positive Strauss reaction.
(3) Serologic test: Indirect red blood cell agglutination test is more than 1:40. Complement binding test with a potency of 1:8 or more has diagnostic significance. It can be positive 1 week after the disease, and the positive rate can reach more than 90% in 4~5 weeks, and the antibody titer can be maintained for about 1 year.
2. Other auxiliary examinations
X-ray examination.
Diagnosis
This disease has a strict regional nature, a patient who lives in an endemic area or has a history of traveling, occurs any unexplained septic disease or fever, or manifests tuberculosis on X-ray and cannot isolate tubercle bacilli, etc., should consider the possibility of nosocomial disease. The diagnosis can be made in conjunction with laboratory tests.
Treatment
The treatment program varies according to the type of disease. Acute septic cases must be treated with strong antimicrobial therapy, using a combination of two sensitive antibiotics at an early stage. Tetracycline or chloramphenicol can be used in combination with kanamycin, sulfadiazine, sulfamethoxazole, methotrexate, or sulfisoxazole for intravenous or intramuscular injection.
Surgical incision and drainage is preferred for abscesses, and surgical incision and drainage of the lesion can be used in chronic cases where medical treatment is ineffective.