Table 2. Common misconceptions and pitfalls in the identification of Burkholderia pseudomallei and diagnosis of melioidosis.

Misconception or pitfall	Comments
Melioidosis is endemic only to some parts of Asia and northern Australia.	Melioidosis is reported in many regions of the world, including regions of Central and South America, various Pacific and Indian Ocean islands, and some countries in Africa.
Melioidosis is not endemic to the area because B. pseudomallei has never been reported from the microbiological facilities.	B. pseudomallei can be misidentified as another Burkholderia species, Pseudomonas spp., or other organisms, especially by laboratory staff unfamiliar with B. pseudomallei.
Melioidosis is only an acute, septic illness.	10%–15% of patients have chronic disease that may mimic other conditions, including tuberculosis.
Lifetime travel history to non–melioidisos-endemic areas is not taken.	Melioidosis may appear many years after exposure.
Do not provide treatment for melioidosis unless any diagnostic test is positive.	Melioidosis is often fatal, and treatment effective against B. pseudomallei should be provided immediately if melioidosis is suspected.
Throat swab and urine specimens should be collected only from patients with symptoms of pharyngitis or urinary tract infection.	Swabs of throat (anterior fauces) or urine may be positive in patients without focal symptoms.
Culture is a sensitive method for diagnosing melioidosis.	As with most infections, the sensitivity of culture depends on the quality of the specimen, and deep, occult sites of infection are also possible.
Indirect hemagglutination assay is a reliable diagnostic test.	Sensitivity and specificity of indirect hemagglutination assay is poor.
B. pseudomallei can be a colonizing organism.	Although chronic infection after treatment has been described, isolation of B. pseudomallei from any body site should be regarded as indicative of disease.
Selective media for B. pseudomallei are not necessary.	Sensitivity of culture is lower and the diagnosis would be missed for many patients if selective media are not used for specimens from nonsterile sites.
The “safety pin” appearance is a reliable characteristic of gram-stained B. pseudomallei.	B. pseudomallei usually stains unevenly but is not always bipolar, whereas other organisms such as Eshcherichia coli or Klebsiella spp. may appear bipolar with gram stain.
Automated microbiology systems can reliably detect B. pseudomallei.	Although these systems are generally reliable, misidentification is not uncommon, particularly in regions where few strains are included in phenotypic databases.