Difference between revisions of "Melioidosis"

Revision as of 09:44, 26 July 2010

(Pseudoglanders)

Caused by Pseudomonas (Malleomyces) pseudomallei, Closely related to P. mallei in horses
Causes disease in sheep, goats and pigs, occasionally other species
Starts as a pyemia and localises in varius tissues, including the lung as abscessation
- Encapsulated abscesses contain yellow, caseous or creamy pus

Pathogenesis:
- Infection via ingestion, inhalation or skin wounds from environment
- Exotoxin, dermonecrotic protease and lecithinase implicated in pathogenicity
- Strain virulence and host immunosuppression important
Clinical infections:
- Opportunistic infection with stress and immunosuppression predisposing to disease
- Abscesses develop in many organs including lungs, spleen, liver, joints, CNS, upper respiratory tract
- Chronic, debilitating, progressive disease with long incubation period
- Many animal species susceptible
- Referred to as pseudoglanders in horses
Diagnosis:
- Specimens: pus from abscesses, affected tissues, blood
- Fluorescent antibody technique on tissue smears
- Blood agar and MacConkey agar plates, incubated aerobically
- Colonies have musty smell
- Lactose fermentation on MacConkey
- Slide agglutination
- ELISA, complement fixation and indirect haemagglutination tests for serum antibodies
Treatment/control: slaughter of infected animals where exotic
Pneumonia and arthritis are the most common presentation

@@ Line 4: / Line 4: @@
 *Starts as a pyemia and localises in varius tissues, including the lung as abscessation
 **Encapsulated abscesses contain yellow, caseous or creamy pus
+*Pathogenesis:
+**Infection via ingestion, inhalation or skin wounds from environment
+**Exotoxin, dermonecrotic protease and lecithinase implicated in pathogenicity
+**Strain virulence and host immunosuppression important
+*Clinical infections:
+**Opportunistic infection with stress and immunosuppression predisposing to disease
+**Abscesses develop in many organs including lungs, spleen, liver, joints, CNS, upper respiratory tract
+**Chronic, debilitating, progressive disease with long incubation period
+**Many animal species susceptible
+**Referred to as pseudoglanders in horses
+*Diagnosis:
+**Specimens: pus from abscesses, affected tissues, blood
+**Fluorescent antibody technique on tissue smears
+**Blood agar and MacConkey agar plates, incubated aerobically
+**Colonies have musty smell
+**Lactose fermentation on MacConkey
+**Slide agglutination
+**ELISA, complement fixation and indirect haemagglutination tests for serum antibodies
+*Treatment/control: slaughter of infected animals where exotic
 *[[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|Pneumonia]] and arthritis are the most common presentation
 [[Category:Respiratory_Bacterial_Infections]][[Category:Sheep]]
+[[Category:To_Do_-_Clinical]]