Burkholderia pseudomallei: Properties, Lab Diagnosis

By Acharya Tankeshwar •  Updated: 06/21/21 •  4 min read

Burkholderia pseudomallei causes a life-threatening disease known as meliodiosis (also called Whitmore’s disease). It is glanders (caused by B. mallei) like disease in animals and humans.

It affects both humans or animals (rats, rabbits, and guinea pigs). Meliodiosis is also called ‘Vietnamese time-bomb disease’ because of its long latent period (it can reactive many years after the primary infection). This organism can be used as a potential agent of biological warfare so CDC has grouped B. pseudomallei and B. mallei as category B bio-threat agents.

Burkholderia pseudomallei on Blood Agar
B.pseudomallei on Blood Agar


Flow diagram to rule out or refer B. mallei.
Image source: Laboratory Response Network (LRN)


Burkholderia is a saprophyte of soil and water. People acquire this infection mostly through

Person to person transmission can occur but rarely.

Virulence Factors

Known virulence factors are:

Clinical Manifestations

Meliodiosis is predominantly a disease of tropical climates especially in Southeast Asia (Thailand, Vietnam, Cambodia, Laos, Malaysia, Myanmar) and northern Australia.

The incubation period is not clearly defined but may range from 2 days to many years. Most infections are asymptomatic or present as a self-limited, flu-like illness. It shows a wide range of signs and symptom which ranges from localized abscess to disseminated infections with CNS manifestations. The mortality rate is approximately 95% in patients with acute disease, if not treated.

Acute Localized Infection: Infection is localized as a nodule and results from inoculation through a break in the skin. Patient generally present with:

Pulmonary Infection: This form of the disease can produce a clinical picture of mild bronchitis to severe pneumonia. Commonly seen signs/symptoms are:

Acute Bloodstream Infection: Patients with underlying illness such as HIV, renal failure, and diabetes may develop this type of infection. The symptoms generally include:

Chronic Suppurative Infection: Chronic melioidosis is a disseminated infection that involves various organs of the body such as joints, viscera, skin, brain, liver, lungs, bones, and spleen.

Laboratory Diagnosis


B. pseudomallei in Gram-stain (image source-Ian Martin, idmic-net).

Sample depends on the site of infection. Sputum and purulent discharge from lesion is commonly used.

Microscopy and Staining

Gram-negative bacilli that typically exhibit a bipolar or safety pin appearance, which is better appreciated when stained with methylene blue.


Burkholderia pseudomallei
Burkholderia pseudomallei on Ashdown’s medium
(image source: Gavin Koh ref-2)

It is an obligate aerobe that grows in various media, e.g. nutrient agar, blood agar and MacConkey agar. Colonies are typically rough and corrugated, similar to the colonies of Pseudomonas stutzeri. Ashdown’s medium is used as selective medium, where it produces wrinkled purple colonies.

Important properties that differentiate it from Pseudomonas stutzeri include

Latex agglutination test: Culture can be confirmed by latex agglutination test using specific antisera.

Antigen detection

Rapid agglutination tests for the detection of B. pseudomallei antigen in urine are available.


Antibodies against B. pseudomallei can be detected and measured in blood.

References and Further Readings

  1. Procop, G. W., & Koneman, E. W. (2016). Koneman’s Color Atlas and Textbook of Diagnostic Microbiology (Seventh, International edition). Lippincott Williams and Wilkins.
  2. Image source: By Gavin Koh – Own work, CC BY-SA 4.0, ttps://commons.wikimedia.org/w/index.php?curid=4975784

Acharya Tankeshwar

Hello, thank you for visiting my blog. I am Tankeshwar Acharya. Blogging is my passion. I am working as an Asst. Professor and Microbiologist at Department of Microbiology and Immunology, Patan Academy of Health Sciences, Nepal. If you want me to write about any posts that you found confusing/difficult, please email at microbeonline@gmail.com