Glanders
Synonym: Farcy, malleus
Definition
- It is a contagious disease of horses, mules and donkeys (solipeds), usually chronic in nature characterised by formation of nodules and ulcers of upper air passages, lungs and cutaneous tissue.
Aetiology
- Pseudomonas mallei (Actinobacillus mallei )
Incidence
- Horses, mules, donkeys, highly susceptible and man is moderately susceptible
- Sheep and goats may be infected.
- The disease is also transmissible to human beings
Transmission
- Ingestion ,inhalation and through skin invasion
Pathogenesis
- Infection is by ingestion and inhalation of organisms
- Penetrating the pharyngeal and intestinal mucosa
- Enters the general circulation and reach pulmonary capillaries
- Septicaemic phase with high temperature
- Forming emboli in the pulmonary capillaries
- Acute inflammatory reaction in the perialveolar and peribronchiolar area
- Serous exudate in the connective tissue
- Penetrate the bronchial wall and enter lumen voided along with secretions
- Aspirate into alveoli produce bronchopneumonia
- Neutrophils undergo degeneration- karyorrhexis and fragments of nucleus seen as scattered manner - Characteristics of glanders in stained smears
- Organisms enters circulation and localized in various organs produce nodules and ulcers in skin
Clinical signs
- Acute: septicaemia with fever
- Chronic : Two forms
- Pulmonary- Chronic cough, pneumonic signs, purulent oily discharge
- Cutaneous form- ulcers, oily pus discharge, coiled tortuous lymphatics
Gross lesions
Lungs
- Miliary nodules
- Pleurisy – fibrinous deposits
- Ulcers in trachea and larynx (punched out)
Lymphatic glands
- Swollen edematous with yellowish grey centers
- Thick tortuous cords of lymph vessels (farcy cords)
- Nodule formation in the lymph vessels (farcy buds)
- Nodules may open and discharge oily pus with persistent ulcers
Microscopic lesions
- The pulmonary lesions are granulomatous with caseous necrotic centre surrounded by epitheliod cells, giant cells and lymphocytes
- Lymphangitis and lymphadenitis of the hind limbs in the form of thick tortuous cords of lymph vessels and nodule formation in lymph vessels.
- The vessels are dilated and tightly packed with leucocytes.
- Leucocytes infiltrate focally into the walls also giving them a beaded appearance. They nodules may open and discharge oily pus
Diagnosis
- Lesions
- Serological tests- CFT
- Guinea pig inoculation (Straus test- male - suppurative orchitis within 4 to 5 days) and confirmation by intradermal mallein test
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Last modified: Wednesday, 21 March 2012, 8:31 AM