Glanders is a severe bacterial disease of a septic-pyemic nature caused by Glanders bacillus – Burkholderia mallei. With disease, intermittent fever, lymphadenitis, muscle abscesses, abscessing pneumonia, purulent arthritis, osteomyelitis, multiple purulent-hemorrhagic pustules on the skin and mucous membranes, turning into glanders ulcers, are noted. The diagnosis is confirmed by microscopic, bacteriological, serological studies, biological and skin-allergic tests. Antimicrobial and general tonic agents, surgical drainage of abscesses are used in the treatment of glanders.
ICD 10
A24.0 Glanders
General information
Glanders is a dangerous bacterial infection transmitted to humans from ungulates (mainly horses), accompanied by purulent lesions of the lymph nodes, skin, muscles, lungs and other internal organs. Previously, Disease was widespread everywhere, currently the area of infection has narrowed; individual cases of the disease are recorded only in some countries of Asia, Africa and South America. Human infection with glanders is rare and in most cases is associated with the professional activities of persons engaged in horse breeding (animal technicians, veterinarians, grooms, riders, blacksmiths).
Causes
The causative agent is a stationary gram-negative rod Burkholderia mallei, which has a straight or slightly curved shape and a characteristic granular structure. The bacterium has no spores and flagella, and secretes the endotoxin mallein. Bacillus develops in the temperature range from 20 to 45C (optimum – 37C), persists in soil and water for up to 1.5 months, in secretions from the respiratory tract and skin elements of patients, in animal corpses – up to several weeks. The causative agent of glanders is sensitive to heating, the action of ultraviolet light, disinfection agents.
The reservoir and source of the pathogen of glanders in nature are sick ungulates of the equine family (horses, donkeys, mules, mules, less often zebras), as well as camels. Donkeys suffer from glanders in an acute form, horses, usually, in a chronic form. Glanders can also infect predators (lions, tigers, leopards, lynxes) that eat the meat of sick animals. Susceptibility to infection in humans is low. Infection of a person with glanders occurs through direct contact with sick animals, disposal of glanders corpses, through secondary infected surrounding objects (harness, fodder, straw). The penetration of the glanders pathogen is possible by aerogenic means (in laboratory conditions), as well as by alimentary means. Transmission of glanders from person to person is unlikely.
The entrance gates are damaged skin, mucous membranes of the respiratory tract, less often the digestive tract. At the site of the introduction of the pathogen, typical glanders nodules (granulomas) appear. Lymphogenically and hematogenically, glanders rods spread throughout the body, causing a diffuse septic-pyemic process with the formation of secondary multiple abscesses on the skin, in muscles and internal parenchymal organs. Immunity after undergoing glanders is tense and short-lived.
Symptoms
Disease occurs in an acute or primary chronic form. Depending on the leading manifestations of infection, cutaneous, nasal and pulmonary glanders are distinguished. The incubation period of infection is from 2 to 5 days. The acute form of glanders is manifested by a prolonged septic fever (38-40C) with large daily temperature fluctuations; chills, sharp weakness, headache, myalgia and arthralgia.
At the site of the introduction of the glanders stick, a purple-red papule appears on the skin, which quickly builds up and opens, exposing a grayish-dirty ulcer with a greasy bottom and edematous uneven edges. The skin around swells, becomes covered with pustules, crusts and dead tissues. Regional lymphadenitis and lymphangitis are noted. On the 5-7 day after a short-term decrease in temperature, the infection is generalized according to the type of septicopiemia with repeated fever and a sharp deterioration in the general condition of patients. Granulomatous-purulent process with the formation of small multiple abscesses and foci of necrosis spreads to the skin and internal organs, more often the lungs, as well as muscles, cartilage and bones.
Polymorphic inflammatory rashes (spots, papules, hemorrhagic vesicles, pustules) appear on the skin, surrounded by infiltrates, painful and hot to the touch, soon disintegrating and ulcerating. Deep glanders ulcers are located mainly on open areas of the body (face and limbs) and contain thick, viscous greenish pus, sometimes with an admixture of blood. With intranasal penetration of the pathogen, ulcerating granulomas are most pronounced on the nasal mucosa and are accompanied by abundant, mucopurulent, fetid discharge of dirty red color, which dry up with crusts around the nostrils.
Lung damage in glanders is characterized by the formation of glanders nodules, abscesses, the development of small-focal, abscessing or draining pneumonia with persistent deep cough, mucosal-bloody-purulent sputum, chest pain, shortness of breath. Purulent arthritis (joint empyema), osteomyelitis, septic diarrhea may occur. Deep painful abscesses in the muscles (especially the calf) spontaneously open with the formation of characteristic fistulas. The spleen increases dramatically. The acute form of glanders lasts from 7 to 14 days, quickly leading to death.
The chronic form of glanders is characterized by slow development and prolonged (from several months to several years) the course with exacerbations and remissions. There is intoxication, intermittent fever, extensive, long-lasting ulcers and multiple cold-type abscesses in the subcutaneous tissue and muscles (more often limbs), migrating drain pneumonia involving the pleura. Complications of glanders are deep phlegmon, pleuropneumonia, bronchiectasis, pneumosclerosis, general amyloidosis, purulent meningitis, cachexia.
Diagnosis and treatment
The diagnosis of glanders is confirmed by specific clinical signs, detection of bacillus by smear microscopy, isolation and identification of the culture of the pathogen during sowing on nutrient media, positive results of serological reactions (IFT, AR), skin allergic and biological tests. The clinical material for research is purulent discharge of skin ulcers, nasal discharge, sputum, blood, the contents of abscesses obtained by puncture of lymph nodes and subcutaneous ulcers, pieces of cadaveric tissue. With the help of bacterial inoculation of the material on the microflora in the acute form of glanders, the characteristic growth of B.mallei culture is determined in the form of a slimy amber-brown plaque, gradually becoming cloudy and acquiring a reddish hue.
A biological test conducted on male guinea pigs reveals the high pathogenicity of glanders bacillus for laboratory animals and allows us to examine samples of various organs and tissues. From 2-3 weeks of the disease, a positive skin allergy test with mallein is manifested. The main serological method for the diagnosis of acute glanders is IFT, conducted in dynamics and determining the increase in the titer of specific antibodies. Chest X-ray in the pulmonary form of glanders reveals signs of small-focal or drain pneumonia with darkening of the lobe of the lung, as well as focal shadows and cavities during lung abscess. Disease must be differentiated from sepsis, plague, anthrax, smallpox, erysipelas, syphilis, abscess or tuberculosis of the lungs, pulmonary mycoses, melioidosis.
In case, isolation of the patient in an infectious hospital is mandatory. As an etiotropic treatment, antimicrobial drugs are prescribed – sulfonamides (usually sulfatiazole) alone or in combination with streptomycin, benzylpenicillin, aminoglycosides. Vitamin therapy, transfusion of blood substitutes, oxygen therapy are shown. Surgical drainage of the formed abscesses is performed. A positive effect in the treatment can be achieved by subcutaneous or intradermal administration of increasing doses of glycerin extract from bacilli. In the septic form, intensive care measures are needed to maintain the function of vital organs. Treatment of mild cases of glanders lasts at least 30 days, severe cases – longer.
Prognosis and prevention
The prognosis is quite serious. Mortality in the untreated acute form is approaching 100%, with chronic occurs in half or more cases. Timely treatment allows us to hope for more favorable prospects. In order to prevent glanders, veterinary control, early detection and slaughter of sick animals, compliance with the rules of personal protection when caring for animals with suspected glanders (wearing protective overalls, gloves, masks, glasses), disinfection of places where these animals are kept are organized. For persons who have been in contact with patients, a 21-day quarantine is established. Infected, but not yet infected with SAP patients, emergency prevention with sulfatiazole is performed.
