Melioidosis
Melioidosis is infection with Burkholderia pseudomallei, a CDC Class B bioterrorism agent endemic to Southeast and East Asia that presents in returning travelers as pneumonia or pyogenic hepatic abscess and is treated with IV ceftazidime or meropenem followed by oral trimethoprim-sulfamethoxazole.
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What this article covers
- Overview
Infection with Burkholderia pseudomallei, an organism classified by the Centers for Disease Control and Prevention (CDC) as a Class B bioterrorism agent, listed alongside glanders, Q fever, brucellosis, and tularemia in this category.
- Epidemiology
Endemic to Southeast and East Asia, the geographic region associated with Burkholderia pseudomallei in the same category as SARS and avian influenza as travel-related respiratory pathogens.
- Risk factors
Recent travel to Southeast Asia, the exposure explicitly linked to Burkholderia pseudomallei as a cause of visceral (hepatic) abscess.
- Pathophysiology
The mechanism of tissue invasion is not fully characterized for Burkholderia pseudomallei; its recognized clinical consequences are pyogenic visceral (hepatic) abscess formation and pneumonia…
- Clinical features
Pyogenic (hepatic) visceral abscess, presenting as one of the recognized causes of liver abscess, with the general pattern for pyogenic liver abscess of fever, abdominal pain, elevated white blood…
- Differential diagnosis
Glanders (Burkholderia mallei): a related Class B bioterrorism agent transmitted by contact with tissues or bodily fluids of infected mules or horses, producing pustules with suppurative localized…
- Diagnosis
Diagnosis is confirmed by isolation (culture) of Burkholderia pseudomallei from the relevant clinical specimen, following the same general pattern applied to other pyogenic organisms in this…
- Management
First, achieve source control of any visceral abscess: percutaneous aspiration of a hepatic abscess is both diagnostic and therapeutic and should be pursued alongside antimicrobial therapy.
- Complications
Visceral (hepatic) abscess formation, with the attendant risks of rupture or extension if not drained.
- Prognosis
Specific mortality and outcome figures are not well established for melioidosis; general principles from the related pyogenic-abscess and travel-pneumonia contexts apply, including the value of…
- Prevention
Elicit a detailed travel history in any patient presenting with fever, pneumonia, or a visceral abscess, specifically asking about Southeast or East Asia travel, since this exposure is the identified risk factor for this organism.
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