Glanders
Glanders– an acute infectious disease caused by the pathogen Pseudomonas (Burkholderia) mallei and proceeding with the formation of specific granulomas, necrosis, suppuration of the affected tissues and intoxication. Epidemiology. The source of the infectious agent is horses, donkeys, camels, less often goats, dogs and cats; among laboratory animals, hamsters and guinea pigs are sensitive. Occupational disease. The route of infection is contact. Sporadic cases are recorded in Asia, Africa, Central and South America. Pathogenesis. The development of an acute inflammatory reaction with the formation of foci of purulent fusion of tissues, due to the release of endotoxin. When infected with a small dose of the pathogen or a weakly virulent strain, the formation of granulomas at the site of the pathogen introduction and their caseous necrosis are observed. The destruction of the primary foci contributes to the lympho- and hematogenous spread of the pathogen throughout the body. The process acquires a septic-pyemic character with the formation of abscesses in the muscles and internal organs (most often in the lungs, liver, spleen).
Clinical picture
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- Sharp form. The incubation period is 1-5 days. The disease begins acutely with a rise in body temperature to 38-39 ° C, headaches and joint pain. At the site of penetration of the pathogen, a dark red papule subsequently forms, then a pustule with undermined edges and a greasy bottom. Often the formation of foci accompanies regional lymphangitis. Later (after 5-7 days) a secondary multiple appearance of ulcerating papules is noted. The condition of the patient deteriorates sharply, manifestations of severe pleuropneumonia with hemoptysis are observed, less often – abscessing lesions of other organs. Lethality reaches 100%.
- Chronic form
- The most common cutaneous form is characterized by multiple chronic cold abscesses. Their spontaneous opening is accompanied by the formation of fistulas with abundant discharge containing the pathogen (the pathogen is absent during surgical opening)
- In the nasopharyngeal form, mucopurulent discharge, the formation of yellow-green crusts and the spread of ulceration to the pharynx and trachea are typical.
- The pulmonary form is characterized by pleuropneumonia and muscle abscesses.
- The prognosis is unfavorable, mortality is 50% or more.
Diagnostics
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- Isolation of the pathogen. Material for research – sputum, pus, blood discharge from opened abscesses, biopsy material from closed abscesses
- After isolation of suspicious colonies, a biological test is carried out on guinea pigs. The mixed culture is injected subcutaneously, pure – intraperitoneally. A granuloma appears at the injection site after 2-3 days,
opening for 4-5 days with the formation of an ulcer. On days 3–10, male guinea pigs infected intraperitoneally develop a characteristic testicular lesion (Strauss phenomenon)
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- Skin test. The patient is injected intravenously (on the inside of the forearm) with mallein at a dilution of 1:100 (0.1 ml). The reaction is used for epidemiological studies.
Differential Diagnosis
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- Melioidosis
- herpetic infection
- anthrax
- Chancroid
- Syphilis
- Tuberculosis
- anaerobic infections.
Treatment
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- Patients are placed in isolated wards with a strict regime. For their service, qualified personnel are involved, observing all precautions and using personal protective equipment (overalls; in their absence, gloves, gowns, masks, glasses, gauze bandages, etc.)
- Opening abscesses or cauterizing them, topical application of antiseptic ointments
- If parenteral use of antimicrobial products is needed
- Tobramycin or gentamicin 5 mg/kg/day, if effective, as well as in violation of kidney function, the dose is reduced to 3 mg/kg/day
- If aminoglycosides fail, amikacin
- p-Lactam antibiotics (carbenicillin, ticarcillin, piperacillin, ceftazidime, aztreonam, imipenem, ciprofloxacin [for gastrointestinal lesions]), fluoroquinolone derivatives.
Prevention. Identification and destruction of diseased or mallein-positive animals. Persons exposed to the risk of infection, in the absence of clinical manifestations for 21 days and negative results of repeated skin tests, are released from quarantine.