Skip to content
How It Works
Explore
Resources Ask a Question
Who It's For
Patients Caregivers Providers
Log In Ask a Question
PubMed This is a summary of 22 peer-reviewed journal articles Updated
Infectious Disease

Understanding Your Lab Results and Diagnosis

At a Glance

Melioidosis is highly difficult to diagnose because standard automated hospital lab tests frequently misidentify the bacteria. The most accurate way to confirm a diagnosis is through a specialized bacterial culture using Ashdown's agar, or advanced molecular tests like PCR and MALDI-TOF MS.

Deciphering laboratory reports for melioidosis can be frustrating because the diagnosis is notoriously difficult to secure. In many cases, the bacteria responsible for your illness may have been misidentified or overlooked by standard hospital tests [1][2]. Understanding the “gold standard” of diagnosis will help you advocate for the most accurate information regarding your condition.

The Gold Standard: Bacterial Culture

The most reliable way to diagnose melioidosis is through a bacterial culture [3]. This involves taking samples of your blood, sputum, urine, or pus from an abscess and attempting to grow the bacteria (Burkholderia pseudomallei) in a laboratory setting [3][4].

Because B. pseudomallei can grow slowly and be crowded out by other common bacteria, specialized labs often use Ashdown’s agar [3]. This is a “selective” growth medium specifically designed to allow this bacterium to thrive while stopping the growth of others [5]. Under a microscope, these bacteria sometimes have a unique appearance called bipolar staining, which can look like tiny “safety pins” [5].

The Problem with Automated Systems

A major hurdle in diagnosing melioidosis is the reliance on automated commercial identification systems (such as VITEK 2, Phoenix, or API 20NE) [6][7]. These machines are commonly used in hospitals to quickly identify bacteria, but they frequently fail when it comes to B. pseudomallei [6].

The machines often misidentify melioidosis as:

  • Burkholderia cepacia complex (Bcc): A group of related bacteria that are generally less dangerous [8][9].
  • Pseudomonas species: Common bacteria that require very different treatment [6].
  • Burkholderia thailandensis: A “cousin” of the melioidosis bacteria that rarely causes disease [10][11].

If your lab report initially showed one of these names and then “changed” to melioidosis, it is usually because a laboratory professional performed a manual check or a more advanced test [12][6].

What to Look for on Your Lab Report

When reviewing your pathology results, look for these specific methods that provide a higher level of certainty:

  • MALDI-TOF MS: A high-tech laser test that “fingerprints” bacterial proteins. It is much more accurate than automated chemical tests for identifying this species [13][14].
  • PCR (Polymerase Chain Reaction): A molecular test that looks for the actual DNA of the bacteria. It is highly specific and can provide rapid confirmation [15][16].
  • Manual Biochemical Tests: Traditional “bench” tests performed by a microbiologist to verify the results of a machine [3][17].

Why It is Often Misdiagnosed

Because the symptoms of melioidosis are so varied, it is frequently mistaken for other conditions before the lab results come back. It is most commonly misidentified as:

  1. Tuberculosis (TB): Due to similar lung imaging and chronic fever [18][19].
  2. Community-Acquired Pneumonia: Standard lung infections caused by more common bacteria [20].
  3. Pyrexia of Unknown Origin (PUO): A medical term for a persistent fever that doctors cannot initially explain [21].

If you are in a region where melioidosis is rare, ensure your doctors know about any history of travel to tropical areas or the Gulf Coast, as this information is vital for the lab to use the correct diagnostic protocols [1][22].

Return to the Home Page

Common questions in this guide

What is the gold standard test for diagnosing melioidosis?
The most reliable way to diagnose melioidosis is through a bacterial culture. This involves taking samples of blood, sputum, urine, or pus and growing the bacteria in a lab, often using a specialized medium called Ashdown's agar to prevent other bacteria from hiding it.
Why do hospitals often misdiagnose melioidosis?
Standard automated testing machines used in many hospitals frequently misidentify the bacteria that causes melioidosis as other, less dangerous bacteria. In addition, the infection's varied symptoms often lead doctors to initially suspect more common conditions like tuberculosis or pneumonia.
What advanced tests are used to confirm a melioidosis diagnosis?
To provide a higher level of certainty, laboratories may use advanced tests like MALDI-TOF MS, which fingerprints bacterial proteins, or PCR testing, which looks for the actual DNA of the bacteria. These methods are much more accurate than automated chemical tests.
Why does my doctor need to know my travel history for lab tests?
Melioidosis is rare in many regions but more common in tropical areas and the Gulf Coast. Telling your doctor about travel to these areas or exposure to soil and water alerts the laboratory to use the specific diagnostic protocols needed to find the bacteria.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Was this diagnosis confirmed using a manual culture or molecular test rather than just an automated system?
  2. 2.Did the lab use selective media like Ashdown’s agar to ensure other bacteria didn't hide the B. pseudomallei?
  3. 3.Could my symptoms have been initially mistaken for tuberculosis or a common pneumonia?
  4. 4.Does the lab that processed my sample have experience identifying this specific bacterium?
  5. 5.Were my samples sent to a state public health laboratory or the CDC for confirmation?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (22)
  1. 1

    Whole Genome Sequencing and Comparative Genomics of the Emerging Pathogen Burkholderia pseudomallei Isolated from Two Travel-Related Infections in Hungary.

    Henczkó J, Tóth Á, Knausz M, et al.

    Pathogens (Basel, Switzerland) 2025; (14(11)) doi:10.3390/pathogens14111108.

    PMID: 41305346
  2. 2

    Multi-systemic melioidosis.

    Nagoba BS, Dhotre SV, Rayate AS, et al.

    World journal of clinical cases 2024; (12(28)):6151-6154 doi:10.12998/wjcc.v12.i28.6151.

    PMID: 39371552
  3. 3

    Comprehensive approaches for the detection of Burkholderia pseudomallei and diagnosis of melioidosis in human and environmental samples.

    Oslan SNH, Yusoff AH, Mazlan M, et al.

    Microbial pathogenesis 2022; (169()):105637 doi:10.1016/j.micpath.2022.105637.

    PMID: 35710088
  4. 4

    Burkholderia pseudomallei and melioidosis.

    Meumann EM, Limmathurotsakul D, Dunachie SJ, et al.

    Nature reviews. Microbiology 2024; (22(3)):155-169 doi:10.1038/s41579-023-00972-5.

    PMID: 37794173
  5. 5

    Phylogenetic and phenotypic characterization of Burkholderia pseudomallei isolates from Ghana reveals a novel sequence type and common phenotypes.

    Schully KL, Voegtly LJ, Rice GK, et al.

    Frontiers in microbiology 2024; (15()):1401259 doi:10.3389/fmicb.2024.1401259.

    PMID: 39044950
  6. 6

    Misidentification of Burkholderia pseudomallei, China.

    Wu B, Tong X, He H, et al.

    Emerging infectious diseases 2021; (27(3)):964-966 doi:10.3201/eid2703.191769.

    PMID: 33622484
  7. 7

    Influence of Biochemical Features of Burkholderia pseudomallei Strains on Identification Reliability by Vitek 2 System.

    Zakharova IB, Lopasteyskaya YA, Toporkov AV, Viktorov DV

    Journal of global infectious diseases 2018; (10(1)):7-10 doi:10.4103/jgid.jgid_39_17.

    PMID: 29563716
  8. 8

    Workflow for Identification of Burkholderia pseudomallei Clinical Isolates in Myanmar.

    Aung NM, Su KK, Chantratita N, Tribuddharat C

    Japanese journal of infectious diseases 2023; (76(2)):106-112 doi:10.7883/yoken.JJID.2022.508.

    PMID: 36450576
  9. 9

    Possible misidentification of species in the Pseudomonas fluorescens lineage as Burkholderia pseudomallei and Francisella tularensis, and emended descriptions of Pseudomonas brenneri,Pseudomonas gessardii and Pseudomonas proteolytica.

    van den Beld MJC, Reinders E, Notermans DW, Reubsaet FAG

    International journal of systematic and evolutionary microbiology 2016; (66(9)):3420-3425 doi:10.1099/ijsem.0.001206.

    PMID: 27259517
  10. 10

    Evaluation of the Bruker Biotyper Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry System for Identification of Clinical and Environmental Isolates of Burkholderia pseudomallei.

    Wang H, Chen YL, Teng SH, et al.

    Frontiers in microbiology 2016; (7()):415 doi:10.3389/fmicb.2016.00415.

    PMID: 27092108
  11. 11

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for the identification of Burkholderia pseudomallei from Asia and Australia and differentiation between Burkholderia species.

    Suttisunhakul V, Pumpuang A, Ekchariyawat P, et al.

    PloS one 2017; (12(4)):e0175294 doi:10.1371/journal.pone.0175294.

    PMID: 28384252
  12. 12

    A simple laboratory algorithm for diagnosis of melioidosis in resource-constrained areas: a study from north-central Vietnam.

    Trinh TT, Hoang TS, Tran DA, et al.

    Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases 2018; (24(1)):84.e1-84.e4 doi:10.1016/j.cmi.2017.07.029.

    PMID: 28780059
  13. 13

    Identification of Burkholderia pseudomallei by Use of the Vitek Mass Spectrometer.

    Gassiep I, Armstrong M, Norton RE

    Journal of clinical microbiology 2019; (57(5)) doi:10.1128/JCM.00081-19.

    PMID: 30842230
  14. 14

    Evaluation of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for identifying Burkholderia pseudomallei and Burkholderia thailandensis isolates.

    Li J, Hu W, Zhang F, et al.

    European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology 2019; (38(1)):191-196 doi:10.1007/s10096-018-3415-3.

    PMID: 30426332
  15. 15

    Diagnosis of melioidosis: the role of molecular techniques.

    Gassiep I, Burnard D, Bauer MJ, et al.

    Future microbiology 2021; (16()):271-288 doi:10.2217/fmb-2020-0202.

    PMID: 33595347
  16. 16

    Synchronous detection of Burkholderia pseudomallei and its ceftazidime resistance mutation based on RNase-HII hydrolysis combined with lateral flow strip assay.

    Yao J, Zhang Z, Tian S, et al.

    Microbiology spectrum 2023; (11(6)):e0112523 doi:10.1128/spectrum.01125-23.

    PMID: 37815337
  17. 17

    Generation of Distinct Differentially Culturable Forms of Burkholderia following Starvation at Low Temperature.

    Auty JM, Jenkins CH, Hincks J, et al.

    Microbiology spectrum 2022; (10(1)):e0211021 doi:10.1128/spectrum.02110-21.

    PMID: 34985335
  18. 18

    Pulmonary Melioidosis Masquerading As Tuberculosis: A Case Report Presenting a Rare Medical Condition From Western India.

    Gaikwad N, Makashir PA, Kelkar R, et al.

    Cureus 2025; (17(10)):e95272 doi:10.7759/cureus.95272.

    PMID: 41287745
  19. 19

    Burkholderia pseudomallei infection presenting with a lung abscess and osteomyelitis in an adult man: A case report.

    Huang L, Yang Z, Zhou XP, Wu JR

    Medicine 2018; (97(35)):e12145 doi:10.1097/MD.0000000000012145.

    PMID: 30170455
  20. 20

    Laboratory Investigations in Patients with Community Acquired Sepsis and/or Pneumonia Caused by Burkholderia pseudomallei.

    Behera B, Radhakrishnanan A, Mishra B, et al.

    The American journal of tropical medicine and hygiene 2022;.

    PMID: 35344934
  21. 21

    Melioidosis: misdiagnosed in Nepal.

    Shrestha N, Adhikari M, Pant V, et al.

    BMC infectious diseases 2019; (19(1)):176 doi:10.1186/s12879-019-3793-x.

    PMID: 30782129
  22. 22

    Clinical presentation and treatment of melioidosis in the head and neck region.

    Mahawerawat K, Kasemsiri P

    The Journal of laryngology and otology 2018; (132(9)):827-831 doi:10.1017/S0022215118001391.

    PMID: 30180912

This page explains melioidosis laboratory tests for educational purposes only. Always consult your infectious disease specialist or primary care doctor to interpret your specific pathology report and diagnosis.

Get notified when new evidence is published on Melioidosis.

We monitor PubMed for new peer-reviewed studies on this topic and email a short summary when something meaningful changes.