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Adhesion and invasion attributes of Burkholderia pseudomallei are dependent on airway surface liquid and glucose concentrations in lung epithelial cells

Mariappan V, Thimma J, Vellasamy KM, Shankar EM, Vadivelu J

Environ Microbiol Rep, 2018 04;10(2):217-225.
PMID: 29393577 DOI: 10.1111/1758-2229.12624

Physiological constituents in airway surface liquids (ASL) appear to impact the adherence and invasion potentials of Burkholderia pseudomallei contributing to recrudescent melioidosis. Here, we investigated the factors present in ASL that is likely to influence bacterial adhesion and invasion leading to improved understanding of bacterial pathogenesis. Six B. pseudomallei clinical isolates from different origins were used to investigate the ability of the bacteria to adhere and invade A549 human lung epithelial cells using a system that mimics the physiological ASL with different pH, NaCl, KCl, CaCl2 and glucose concentrations. These parameters resulted in markedly differential adherence and invasion abilities of B. pseudomallei to the lung epithelial cells. The concentration of 20 mM glucose dramatically increased adherence and invasion by increasing the rate of pili formation in depiliated bacteria. Glucose significantly increased adherence and invasion of B. pseudomallei to A549 cells, and presence of NaCl, KCl and CaCl2 markedly ablated the effect despite the presence of glucose. Our data established a link between glucose, enhanced adhesion and invasion potentials of B. pseudomallei, hinting increased susceptibility of individuals with diabetes mellitus to clinical melioidosis.

Matched MeSH terms: Melioidosis/microbiology
A Case of Constrictive Pericarditis Associated with Melioidosis in an Immunocompetent Patient Treated by Pericardiectomy

Lu HT, Ramsamy G, Lee CY, Syed Hamid SRG, Kan FK, Nordin RB

Am J Case Rep, 2018 Mar 19;19:314-319.
PMID: 29551765

BACKGROUND Melioidosis is a rare tropical bacterial infection caused by the Gram-negative soil saprophyte, Burkholderia pseudomallei. Melioidosis can mimic a variety of diseases due to its varied presentation, and unless it is treated rapidly, it can be fatal. A rare case of melioidosis, with pericarditis and pericardial effusion, is described, which demonstrates the value of early diagnosis with echocardiography and pericardiocentesis. CASE REPORT A 38-year-old native (Iban) East Malaysian man presented with shortness of breath and tachycardia. Transthoracic echocardiography (TTE) showed cardiac tamponade. Urgent pericardiocentesis drained a large amount of purulent pericardial fluid that grew Burkholderia pseudomallei. Despite appropriate dose and duration of intravenous treatment with ceftazidime followed by meropenem, the patient developed recurrent pericardial effusion and right heart failure due to constrictive pericarditis. The diagnosis of constrictive pericarditis was confirmed by computed tomography (CT) and surgical exploration. Following pericardiectomy, his symptoms resolved, but patient follow-up was recommended for possible sequelae of constrictive pericarditis. CONCLUSIONS After the onset of melioidosis pericarditis, the authors recommend follow-up and surveillance for possible complication of constrictive pericarditis.

Matched MeSH terms: Melioidosis/microbiology
Fulltext Comparison by electron microscopy of intracellular events and survival of Burkholderia pseudomallei in monocytes from normal subjects and patients with melioidosis

Puthucheary SD, Nathan SA

Singapore Med J, 2006 Aug;47(8):697-703.
PMID: 16865211

Burkholderia pseudomallei (B. pseudomallei) has been shown to persist intracellularly in patients with melioidosis, until reactivated by decreasing immunocompetence. We have previously demonstrated by transmission electron microscopy, the internalisation of B. pseudomallei by human macrophages and the occurrence of phagosome-lysosome fusion.

Matched MeSH terms: Melioidosis/microbiology
Fulltext Sequence polymorphism and PCR-restriction fragment length polymorphism analysis of the flagellin gene of Burkholderia pseudomallei

Tay ST, Cheah PC, Puthucheary SD

J Clin Microbiol, 2010 Apr;48(4):1465-7.
PMID: 20089759 DOI: 10.1128/JCM.01131-09

Four flagellin allelic types (I to IV) of Burkholderia pseudomallei were identified based on their sequence variation and restriction fragment length polymorphism (RFLP) analysis of the amplified flagellin gene. Flagellin allelic type I was the most predominantly (75.0%) found among the 100 clinical isolates of B. pseudomallei investigated in this study.

Matched MeSH terms: Melioidosis/microbiology
Antimicrobial susceptibility patterns of Burkholderia pseudomallei among melioidosis cases in Kedah, Malaysia

Hassan MR, Vijayalakshmi N, Pani SP, Peng NP, Mehenderkar R, Voralu K, et al.

Southeast Asian J Trop Med Public Health, 2014 May;45(3):680-8.
PMID: 24974653

Burkholderia pseudomallei, the causative agent of melioidosis is an important cause of morbidity and mortality particularly among diabetics. We evaluated 228 isolates of B. pseudomallei for antimicrobial sensitivity during 2005-2010 using the disc diffusion technique, of which 144 were obtained from blood culture. More than 90% of the strains were susceptible to cefoperazone, ceftazidime, chloramphenicol and imipenem. Eighty-two percent of the isolates were susceptible to tetracycline and amoxicillin/clavulanate. The susceptibilities to ciprofloxacin was 78% and to trimethoprim-sulfamethoxezole was 47%. The susceptibilities to aminoglycoside antibiotics were low (21% to gentamicin and 6% to amikacin). The susceptibilities were similar between isolates from females and males, bacteremic and abacteremic cases, diabetics and non-diabetics, pneumonia and non-pneumonia cases and between those who died and those who survived. Our findings show antibiotic susceptibility patterns are not a major factor in determining outcomes of B. pseudomallei infection. Monitoring the drug susceptibilities among B. pseudomallei isolates needs to be conducted regularly to guide empiric therapy for melioidosis, as it causes high mortality, especially among diabetic cases.

Matched MeSH terms: Melioidosis/microbiology*
DNA fingerprinting of septicemic and localized Burkholderia pseudomallei isolates from Malaysian patients

Azura MN, Norazah A, Kamel AG, Zorin SA

Southeast Asian J Trop Med Public Health, 2011 Jan;42(1):114-21.
PMID: 21323173

We have analysed DNA fingerprinting patterns by pulsed-field gel electrophoresis (PFGE) of 52 unrelated Burkholderia pseudomallei strains isolated from septicemic and localized infections from Malaysian subjects. A total of 38 PFGE types were observed among 36 septicemic and 16 localized strains with no predominant pattern. Type 25 was seen in 2 epidemiologically related strains, suggesting human to human transmission. Twelve PFGE types were shared among 26 strains (21 septicemic and 5 localized) showing close genetic relatedness with coefficient of similarity of 0.81 to 1.0. The other 26 strains (15 septicemic and 11 localized) were unrelated as shown by the similarity coefficient of < 0.8. This study showed that our B. pseudomallei strains in Malaysia were mainly heterogenous with no predominant type both in septicemic or localized strains.

Matched MeSH terms: Melioidosis/microbiology*
Burkholderia thailandensis whole cell antigen cross-reacts with B. pseudomallei antibodies from patients with melioidosis in an immunofluorescent assay

Puthucheary SD, Anuar AS, Tee TS

Southeast Asian J Trop Med Public Health, 2010 Mar;41(2):395-400.
PMID: 20578523

An immunofluorescent assay (IFAT) using whole cell antigen derived from Burkholderia thailandensis used for detection of total antibodies to Burkholderia pseudomallei, was found to compare favorably with a previous published report on a B. pseudomallei IFAT assay. At a 1:20 cut-off titer, the assay had high sensitivity (98.9%) and satisfactory specificity (92.3%), when tested against sera from 94 patients suspected of melioidosis. Sera from 12 patients with culture proven melioidosis gave absolute concordance with the 2 test antigens. No sera from 50 blood donors had a titer of > or =20. Cross-reactivity with patients' sera positive for Chlamydia, Mycoplasma, Legionella and typhoid was not observed, except for 3 sera from typhus patients and one from a patient with leptospirosis. The major advantage of this assay is that the cultivation and preparation of B. thailandensis as antigen can be carried out in any laboratory with basic microbiological set-up. The serodiagnosis of melioidosis can be made safe for medical laboratory personnel, particularly in B. pseudomallei endemic regions.

Matched MeSH terms: Melioidosis/microbiology
Enhanced intracellular survival and epithelial cell adherence abilities of Burkholderia pseudomallei morphotypes are dependent on differential expression of virulence-associated proteins during mid-logarithmic growth phase

Al-Maleki AR, Mariappan V, Vellasamy KM, Shankar EM, Tay ST, Vadivelu J

J Proteomics, 2014 Jun 25;106:205-20.
PMID: 24742602 DOI: 10.1016/j.jprot.2014.04.005

Colony morphology variation is a characteristic of Burkholderia pseudomallei primary clinical isolates, associated with variations in expression of virulence factors. Here, we performed comparative investigations on adhesion, invasion, plaque-forming abilities and protein profiles of B. pseudomallei wild-type (WT) and a small colony variant (SCV). The percentage of SCV adherence to A549 cells was significantly higher (2.73%) than WT (1.91%). In contrast, WT was significantly more efficient (0.63%) than SCV (0.31%) in invasiveness and in inducing cellular damage. Using 2-DE and MALDI TOF/TOF, 263 and 258 protein spots were detected in WT and SCV, respectively. Comparatively, 49 proteins were differentially expressed in SCV when compared with WT. Of these, 31 proteins were up-regulated, namely, nucleoside diphosphate kinase (Ndk), phosphoglycerate kinase (Pgk), thioredoxin (TrxA), putative ferritin DPS-family DNA-binding protein (DPS) and oxidoreductase (AhpC) that are known to be involved in adhesion, intracellular survival and persistence. However, among the 18 down-regulated proteins, enolase (Eno), elongation factor (EF-Tu) and universal stress-related proteins were associated with invasion and virulence. Differences observed in these protein profiles provide ample clues to their association with the morphotypic and phenotypic characteristics of colony variants, providing additional insights into the potential association of B. pseudomallei colony morphotypes with disease pathogenesis.

Matched MeSH terms: Melioidosis/microbiology
Fulltext Cervical abscesses due to co-infection with Burkholderia pseudomallei, Salmonella enterica serovar Stanley and Mycobacterium tuberculosis in a patient with diabetes mellitus

Sulaiman H, Ponnampalavanar S, Mun KS, Italiano CM

BMC Infect Dis, 2013 Nov 09;13:527.
PMID: 24209898 DOI: 10.1186/1471-2334-13-527

BACKGROUND: Infections due to Mycobacterium tuberculosis, Burkholderia pseudomallei and non-typhoidal Salmonella cause significant morbidity and mortality throughout the world. These intracellular pathogens share some common predisposing factors and clinical features. Co-infection with two of these organisms has been reported previously but, to our knowledge, this is the first time that infection with all three has been reported in one person.
CASE PRESENTATION: In September 2010, a 58-year-old diabetic Malaysian male presented with fever and a fluctuant mass on the right side of his neck. B. pseudomallei was isolated from an aspirate of this lesion and there was radiological evidence of disseminated infection in the liver and spleen. The recurrence of clinical symptoms over ensuing months prompted further aspiration and biopsy of a cervical abscess and underlying lymph nodes. Salmonella enterica serovar Stanley and then M. tuberculosis were identified from these specimens by culture and molecular methods. The patient responded to targeted medical management of each of these infections.
CONCLUSION: In endemic settings, a high index of suspicion and adequate tissue sampling are imperative in identifying these pathogenic organisms. Diabetes was identified as a predisposing factor in this case while our understanding of other potential risk factors is evolving.

Matched MeSH terms: Melioidosis/microbiology*
Fulltext Potential immunogenic polypeptides of Burkholderia pseudomallei identified by shotgun expression library and evaluation of their efficacy for serodiagnosis of melioidosis

Puah SM, Puthucheary SD, Chua KH

Int J Med Sci, 2013;10(5):539-47.
PMID: 23532805 DOI: 10.7150/ijms.5516

The search for novel immunogenic polypeptides to improve the accuracy and reliability of serologic diagnostic methods for Burkholderia pseudomallei infection is ongoing. We employed a rapid and efficient approach to identify such polypeptides with sera from melioidosis patients using a small insert genomic expression library created from clinically confirmed local virulent isolates of B. pseudomallei. After 2 rounds of immunoscreening, 6 sero-positive clones expressing immunogenic peptides were sequenced and their identities were: benzoate 1,2-dioxygenase beta subunit, a putative 200 kDa antigen p200, phosphotransferase enzyme family protein, short chain dehydrogenase and 2 hypothetical proteins. These immunogens were then transferred to an ELISA platform for further large scale screening. By combining shotgun expression library and ELISA assays, we identified 2 polypeptides BPSS1904 (benzoate 1,2-dioxygenase beta subunit) and BPSL3130 (hypothetical protein), which had sensitivities of 78.9% and 79.4% and specificities of 88.1% and 94.8%, respectively in ELISA test, thus suggesting that both are potential candidate antigens for the serodiagnosis of infections caused by B. pseudomallei.

Matched MeSH terms: Melioidosis/microbiology*
Cases of melioidosis in a university teaching hospital in Malaysia

Raja NS

J Microbiol Immunol Infect, 2008 Apr;41(2):174-9.
PMID: 18473106

Melioidosis is an infectious disease caused by Burkholderia pseudomallei that is endemic in Southeast Asia and northern Australia and has also been reported from non-endemic areas of the world. Little is known about the antimicrobial susceptibility pattern and the demography of melioidosis patients in Malaysia.

Matched MeSH terms: Melioidosis/microbiology*
Burkholderia pseudomallei: in vitro susceptibility to some new and old antimicrobials

Karunakaran R, Puthucheary SD

Scand. J. Infect. Dis., 2007;39(10):858-61.
PMID: 17852912

The treatment of melioidosis currently involves the use of antimicrobials such as ceftazidime, trimethoprim-sulfamethoxazole, amoxicillin-clavulanate and doxycycline. Evaluation of other antimicrobials with activity against the organism continues to be pursued, however, as the causative organism, B. pseudomallei, may not always be susceptible to the above antimicrobials. This study aimed to test the susceptibility of Malaysian isolates of B. pseudomallei against imipenem, meropenem, ertapenem, moxifloxacin and azithromycin. 80 previously stocked clinical isolates collected between 1978 and 2003 from the UMMC, Kuala Lumpur were tested for in vitro susceptibility to these antimicrobials using the E-test minimum inhibitory concentration method. 100% of isolates were sensitive to imipenem and meropenem, 97.5% were sensitive to trimethoprim-sulfamethozaxole, 37.5% to moxifloxacin, and only a minority was sensitive to ertapenem (7.5%). Using breakpoints for Staphylococcus and Haemophilus, 5.0%-6.3% of isolates were sensitive to azithromycin. In conclusion, our findings support the in vitro efficacy of imipenem, meropenem and trimethoprim-sulfamethoxazole against B. pseudomallei. Moxifloxacin, ertapenem and azithromycin cannot be recommended for the treatment of melioidosis; however, further studies are needed to test the efficacy of azithromycin in combination with quinolones.

Matched MeSH terms: Melioidosis/microbiology*
Unrecognised infection in a cystic fibrosis patient

Asiah K, Hanifah YA, Norzila MZ, Hasniah L, Rusanida A

J Paediatr Child Health, 2006 Apr;42(4):217-8.
PMID: 16630326

We report a 17-year-old Malay boy with cystic fibrosis who over a 14-month period experienced worsening respiratory symptoms and deteriorating lung function. Burkholderia pseudomallei was eventually isolated from his sputum. He improved clinically following treatment for meliodosis and his lung function returned to normal.

Matched MeSH terms: Melioidosis/microbiology
Fulltext Global transcriptional analysis of Burkholderia pseudomallei high and low biofilm producers reveals insights into biofilm production and virulence

Chin CY, Hara Y, Ghazali AK, Yap SJ, Kong C, Wong YC, et al.

BMC Genomics, 2015;16:471.
PMID: 26092034 DOI: 10.1186/s12864-015-1692-0

Chronic bacterial infections occur as a result of the infecting pathogen's ability to live within a biofilm, hence escaping the detrimental effects of antibiotics and the immune defense system. Burkholderia pseudomallei, a gram-negative facultative pathogen, is distinctive in its ability to survive within phagocytic and non-phagocytic cells, to persist in vivo for many years and subsequently leading to relapse as well as the development of chronic disease. The capacity to persist has been attributed to the pathogen's ability to form biofilm. However, the underlying biology of B. pseudomallei biofilm development remains unresolved.

Matched MeSH terms: Melioidosis/microbiology
Case-control investigation on the risk factors of melioidosis in small ruminant farms in Peninsular Malaysia

Musa HI, Hassan L, Shamsuddin ZH, Panchadcharam C, Zakaria Z, Abdul Aziz S, et al.

J Appl Microbiol, 2015 Aug;119(2):331-41.
PMID: 25891038 DOI: 10.1111/jam.12830

Epidemiology of melioidosis is poorly understood because its occurrence is influenced by complex interaction of environmental, climatic, physicochemical and host factors. We investigated the potential risk factors for the exposure to Burkholderia pseudomallei in small ruminants' farms in Peninsular Malaysia.

Matched MeSH terms: Melioidosis/microbiology
Intracoronary blood sampling with a microcatheter for the diagnosis of giant infective coronary aneurysm: Melioidosis of coronary artery mycotic aneurysm

Yew KL, Choy CN, Kam JY, Kang Z

Int J Cardiol, 2015;187:530-1.
PMID: 25863294 DOI: 10.1016/j.ijcard.2015.04.013
Matched MeSH terms: Melioidosis/microbiology*
Localized melioidosis

Raja NS

J Pak Med Assoc, 2003 Aug;53(8):373-4.
PMID: 14558747
Matched MeSH terms: Melioidosis/microbiology
Diagnostic and prognostic value of an immunofluorescent assay for melioidosis

Vadivelu J, Puthucheary SD

Am J Trop Med Hyg, 2000 Feb;62(2):297-300.
PMID: 10813488

Melioidosis caused by Burkholderia pseudomallei is endemic in southeast Asia. The clinical manifestations range from wound infections to acute septicemia. In some cases, recurrence can also occur following complete recovery. Case fatality rates are high and a major factor is the delay in the culture and identification of the bacterium. An immunofluorescent assay (IFAT) using whole-cell antigen for the detection of total antibodies to B. pseudomallei was tested with 650 sera. Using a cut-off value of 1:80, 66 sera from culture-confirmed cases were positive with titers > or = 320. In another 523 sera from patients in which no other etiology could be found, 149 (23.4%) were positive. To monitor disease activity, persistence of antibody levels was investigated on 61 serial sera samples collected from 14 other confirmed cases on follow-up visits while on oral maintenance therapy. The IFAT demonstrated a reduction in titers in cases of localized infections, suggesting that either the infection was being resolved or arrested while septicemic patients maintained high IFAT titers on follow-up, suggesting the possibility of continuous sequestration of antigen from an intracellular source.

Matched MeSH terms: Melioidosis/microbiology
Characterization of Burkholderia pseudomallei isolated in Thailand and Malaysia

Radua S, Ling OW, Srimontree S, Lulitanond A, Hin WF, Yuherman, et al.

Diagn Microbiol Infect Dis, 2000 Nov;38(3):141-5.
PMID: 11109011

A total of 35 Burkholderia pseudomallei isolates from Thailand (16 clinical and eight soil isolates) and Malaysia (seven animal, two isolate each from clinical and soil) were investigated by their antimicrobial resistance, plasmid profiles and were typed by randomly amplified polymorphic DNA analysis. All isolates were found to be resistant to six or more of the 12 antimicrobial agents tested. Only two small plasmids of 1.8 and 2.4 megadalton were detected in two clinical isolates from Thailand. RAPD analysis with primer GEN2-60-09 resulted in the identification of 35 RAPD-types among the 35 isolates. The constructed dendrogram differentiated the 35 isolates into two main clusters and a single isolate. The wide genetic biodiversity among the 35 isolates indicate that RAPD-PCR can be a useful method to differentiate unrelated B. pseudomallei in epidemiological investigation.

Matched MeSH terms: Melioidosis/microbiology*
Fulltext Infected aneurysm after returning from Southeast Asia: think Burkholderia pseudomallei!

Auvens C, Neuwirth C, Piroth L, Blot M

BMJ Case Rep, 2019 May 22;12(5).
PMID: 31122956 DOI: 10.1136/bcr-2018-228856

Melioidosis is a protean disease which is endemic to Southeast Asia and northern Australia. Here, we report a case of infected aortic aneurysm due to Burkholderia pseudomallei in an immunocompetent man 6 months after a trip to northern Malaysia. This patient initially received inappropriate surgical and antibiotic treatment, leading to a peri-prosthetic aortic infection with lumbar spondylitis and contiguous psoas muscle abscess. This case highlights the difficulty of diagnosing melioidosis given its diverse clinical manifestations and the limits of routine microbiological methods to identify B. pseudomallei Melioidosis should be considered a possible diagnosis in individuals with unexplained fever subsequent to travel in an endemic area.

Matched MeSH terms: Melioidosis/microbiology

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