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El-Raghi AA, El-Mezayen MM, Areda HA. Potential effects of probiotics (immunobacteryne; IMB) on growth performance, feed efficacy, blood biochemical, redox balance, nonspecific immunity and heat-shock protein expression of Nile tilapia (Oreochromis niloticus) fingerlings. J Anim Physiol Anim Nutr (Berl) 2024; 108:691-699. [PMID: 38226768 DOI: 10.1111/jpn.13923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 11/27/2023] [Accepted: 12/27/2023] [Indexed: 01/17/2024]
Abstract
The supplementation of aquafeed with probiotics is recommended for feasible aquaculture activities. Therefore, the aim of current study was to investigate the potential effects of probiotics on growth performance, feed utilization, biochemical attributes, redox status and immunity response as well as the transcription of heat-shock protein 70 (HSP70) and insulin-like growth factor-1 (IGF-1) genes of Nile tilapia (Oreochromis niloticus; n = 120). Fish with an initial weight of 8.17 ± 0.02 g/fish were randomly divided into four treatment groups and were fed diets containing 0, 0.5, 1 and 1.5 mg immunobacteryne (IMB)/kg diet respectively. Dietary IMB at 1.5 g/kg diet significantly improved the growth performance, feed consumption and growth hormone secretion of the experimental fish (p < 0.05). The 1 or 1.5 g IMB/kg diet boosted phagocytic activities and innate immune response. Serum total protein, total cholesterol, triglycerides and glucose were significantly increased in the groups that were fed 1 and 1.5 mg IMB/kg diet compared to the control (p < 0.05). Meanwhile, the levels of uric acid, creatinine, liver enzymes (aspartate transaminase and alanine transaminase) and cortisol hormone were significantly reduced in the aforementioned treated groups compared to the control (p < 0.05). All fish fed IMB-supplemented diet showed a significant increase in the expression of IGF-1 gene, while the transcription of HSP70 was significantly decreased (p < 0.05). In conclusion, the dietary inclusion of IMB (1 g/kg diet) enhanced growth promoters, feed efficacy, blood biochemical, redox balance and nonspecific immune responses in Nile tilapia fingerlings.
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Affiliation(s)
- Ali Ali El-Raghi
- Department of Animal, Poultry, and Fish Production, Faculty of Agriculture, Damietta University, Damietta, Egypt
| | | | - Hamada A Areda
- Department of Animal, Poultry, and Fish Production, Faculty of Agriculture, Damietta University, Damietta, Egypt
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2
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Fath El-Bab AF, Majrashi KA, Sheikh HM, Shafi ME, El-Ratel IT, Neamat-Allah ANF, El-Raghi AA, Elazem AYA, Abd-Elghany MF, Abdelnour SA, Abduh MS, Jaremko M, Naiel MAE. Dietary supplementation of Nile tilapia (Oreochromis niloticus) with β-glucan and/or Bacillus coagulans: Synergistic impacts on performance, immune responses, redox status and expression of some related genes. Front Vet Sci 2022; 9:1011715. [PMID: 36213404 PMCID: PMC9537821 DOI: 10.3389/fvets.2022.1011715] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 08/29/2022] [Indexed: 12/12/2022] Open
Abstract
A 14-week feeding study was conducted to assess the effects of feed supplementation with prebiotics β-glucan (BG group) and/or probiotics Bacillus coagulans (BC group) on O. niloticus growth performance, body analysis, intestinal structure, immunological response, and antioxidant status. The fish were equally divided into six groups, as follows: the fish group fed an un-supplemented diet served as a control group; the other fish groups were fed supplemented diets with 0.1 g β-glucan kg−1; 1 g Bacillus coagulans kg−1; 2 g B. coagulans kg−1; 0.1 g β-glucan combined with 1 g B. coagulans kg−1; 0.1 g β-glucan combined with 2 g B. coagulans kg−1. The findings revealed that supplementing B. coagulans and the β-glucan mixture improved growth performance and feed efficiency parameters (RGR and SGR) more than the other groups. The fish flesh analysis revealed increased crude protein and dry matter content and lower lipid and ash levels in the BG and BC supplemented groups than in the Control group. On the other hand, β-glucan and B. coagulans supplementation significantly boosted antioxidant activity and immunological responses in serum as determined by CAT, MDA, lysozyme, and phagocytic activity. Dietary β-glucan and B. coagulans supplementation remarkedly enhanced anterior intestine villus histomorphometry characteristics. Furthermore, B. coagulans, alone or in combination with β-glucan, could reduce HSP70 and IL-1β gene expression while increasing IL-8 and GH gene expression. According to the findings, B. coagulans and/or BG increased growth performance by increasing gut health and morphology. Furthermore, β-glucan and B. coagulans supplementation enhanced Tilapia's body composition, immunological responses, and antioxidant status.
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Affiliation(s)
- Ahmed F. Fath El-Bab
- Department of Animal Production, Faculty of Agriculture, Damietta University, Damietta, Egypt
| | - Kamlah A. Majrashi
- Biological Sciences Department, College of Science & Arts, King Abdulaziz University, Rabigh, Saudi Arabia
| | - Huda M. Sheikh
- Department of Biology, College of Science, University of Jeddah, Jeddah, Saudi Arabia
| | - Manal E. Shafi
- Department of Biological Sciences, Zoology, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ibrahim T. El-Ratel
- Department of Poultry Production, Faculty of Agriculture, Damietta University, Damietta, Egypt
| | - Ahmed N. F. Neamat-Allah
- Department of Clinical Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Ali A. El-Raghi
- Department of Animal Production, Faculty of Agriculture, Damietta University, Damietta, Egypt
| | - Amar Y. Abd Elazem
- Department of Animal Production, Faculty of Agriculture, Damietta University, Damietta, Egypt
| | - Mohamed F. Abd-Elghany
- Department of Animal Production, Faculty of Agriculture, Al-Azhar University, Cairo, Egypt
| | - Sameh A. Abdelnour
- Department of Animal Production, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
| | - Maisa S. Abduh
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
- Center of Excellence in Genomic Medicine Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mariusz Jaremko
- Smart-Health Initiative and Red Sea Research Center, Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Mohammed A. E. Naiel
- Department of Animal Production, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
- *Correspondence: Mohammed A. E. Naiel
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Hii SYF, Ali NA, Ahmad N, Amran F. Comparison of in-house IgM and IgG ELISAs for the serodiagnosis of melioidosis in Malaysia. J Med Microbiol 2017; 66:1623-1627. [PMID: 29048275 PMCID: PMC5845700 DOI: 10.1099/jmm.0.000611] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 09/28/2017] [Indexed: 12/19/2022] Open
Abstract
Melioidosis is an endemic infectious disease in Southeast Asia and northern Australia, caused by Burkholderia pseudomallei. However, the incidence rate in Malaysia is not well documented. The high mortality rate and broad range of clinical presentations require rapid and accurate diagnosis for appropriate treatment. This study compared the efficacy of in-house IgM and IgG ELISA methods using a local B. pseudomallei strain. The diagnostic accuracy of the in-house IgG ELISA was better than that of the IgM ELISA: sensitivity (IgG: 84.71 %, IgM: 76.14 %) and specificity (IgG: 93.64 %, IgM: 90.17 %); positive predictive value (IgG: 86.75 %, IgM: 79.76 %) and negative predictive value (IgG: 92.57 %, IgM: 89.66 %); likelihood ratio (LR) [IgG: 13.32, IgM: 7.75 (LR+); IgG: 0.16, IgM: 0.26 (LR-)], and was supported by the observation of the absorbance value in comparisons between culture and serology sampling. In-house IgG ELISA was shown to be useful as an early diagnostic tool for melioidosis.
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Affiliation(s)
- Shirley Yi Fen Hii
- Bacteriology Unit, Infectious Diseases Research Centre, Institute for Medical Research, 50588 Jalan Pahang, Kuala Lumpur, Malaysia
| | - Noor Azila Ali
- Bacteriology Unit, Infectious Diseases Research Centre, Institute for Medical Research, 50588 Jalan Pahang, Kuala Lumpur, Malaysia
| | - Norazah Ahmad
- Bacteriology Unit, Infectious Diseases Research Centre, Institute for Medical Research, 50588 Jalan Pahang, Kuala Lumpur, Malaysia
| | - Fairuz Amran
- Bacteriology Unit, Infectious Diseases Research Centre, Institute for Medical Research, 50588 Jalan Pahang, Kuala Lumpur, Malaysia
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Lowe CW, Satterfield BA, Nelson DB, Thiriot JD, Heder MJ, March JK, Drake DS, Lew CS, Bunnell AJ, Moore ES, O'Neill KL, Robison RA. A Quadruplex Real-Time PCR Assay for the Rapid Detection and Differentiation of the Most Relevant Members of the B. pseudomallei Complex: B. mallei, B. pseudomallei, and B. thailandensis. PLoS One 2016; 11:e0164006. [PMID: 27736903 PMCID: PMC5063335 DOI: 10.1371/journal.pone.0164006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 09/19/2016] [Indexed: 11/24/2022] Open
Abstract
The Burkholderia pseudomallei complex classically consisted of B. mallei, B. pseudomallei, and B. thailandensis, but has now expanded to include B. oklahomensis, B. humptydooensis, and three unassigned Burkholderia clades. Methods for detecting and differentiating the B. pseudomallei complex has been the topic of recent research due to phenotypic and genotypic similarities of these species. B. mallei and B. pseudomallei are recognized as CDC Tier 1 select agents, and are the causative agents of glanders and melioidosis, respectively. Although B. thailandensis and B. oklahomensis are generally avirulent, both display similar phenotypic characteristics to that of B. pseudomallei. B. humptydooensis and the Burkholderia clades are genetically similar to the B. pseudomallei complex, and are not associated with disease. Optimal identification of these species remains problematic, and PCR-based methods can resolve issues with B. pseudomallei complex detection and differentiation. Currently, no PCR assay is available that detects the major species of the B. pseudomallei complex. A real-time PCR assay in a multiplex single-tube format was developed to simultaneously detect and differentiate B. mallei, B. pseudomallei, and B. thailandensis, and a common sequence found in B. pseudomallei, B. mallei, B. thailandensis, and B. oklahomensis. A total of 309 Burkholderia isolates and 5 other bacterial species were evaluated. The assay was 100% sensitive and specific, demonstrated sensitivity beyond culture and GC methods for the isolates tested, and is completed in about an hour with a detection limit between 2.6pg and 48.9pg of gDNA. Bioinformatic analyses also showed the assay is likely 100% specific and sensitive for all 84 fully sequenced B. pseudomallei, B. mallei, B. thailandensis, and B. oklahomensis strains currently available in GenBank. For these reasons, this assay could be a rapid and sensitive tool in the detection and differentiation for those species of the B. pseudomallei complex with recognized clinical and practical significance.
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Affiliation(s)
- Chinn-Woan Lowe
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Benjamin A. Satterfield
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Daniel B. Nelson
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Joseph D. Thiriot
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Michael J. Heder
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Jordon K. March
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - David S. Drake
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Cynthia S. Lew
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Annette J. Bunnell
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Emily S. Moore
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Kim L. O'Neill
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Richard A. Robison
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
- * E-mail:
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Suttisunhakul V, Wuthiekanun V, Brett PJ, Khusmith S, Day NPJ, Burtnick MN, Limmathurotsakul D, Chantratita N. Development of Rapid Enzyme-Linked Immunosorbent Assays for Detection of Antibodies to Burkholderia pseudomallei. J Clin Microbiol 2016; 54:1259-68. [PMID: 26912754 PMCID: PMC4844749 DOI: 10.1128/jcm.02856-15] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 02/06/2016] [Indexed: 01/04/2023] Open
Abstract
Burkholderia pseudomallei, the causative agent of melioidosis, is an environmental bacillus found in northeast Thailand. The mortality rate of melioidosis is ∼40%. An indirect hemagglutination assay (IHA) is used as a reference serodiagnostic test; however, it has low specificity in areas where the background seropositivity of healthy people is high. To improve assay specificity and reduce the time for diagnosis, four rapid enzyme-linked immunosorbent assays (ELISAs) were developed using two purified polysaccharide antigens (O-polysaccharide [OPS] and 6-deoxyheptan capsular polysaccharide [CPS]) and two crude antigens (whole-cell [WC] antigen and culture filtrate [CF] antigen) of B. pseudomallei The ELISAs were evaluated using serum samples from 141 culture-confirmed melioidosis patients from Thailand along with 188 healthy donors from Thailand and 90 healthy donors from the United States as controls. The areas under receiver operator characteristic curves (AUROCC) using Thai controls were high for the OPS-ELISA (0.91), CF-ELISA (0.91), and WC-ELISA (0.90), while those of CPS-ELISA (0.84) and IHA (0.72) were lower. AUROCC values using U.S. controls were comparable to those of the Thai controls for all ELISAs except IHA (0.93). Using a cutoff optical density (OD) of 0.87, the OPS-ELISA had a sensitivity of 71.6% and a specificity of 95.7% for Thai controls; for U.S. controls, specificity was 96.7%. An additional 120 serum samples from tuberculosis, scrub typhus, or leptospirosis patients were evaluated in all ELISAs and resulted in comparable or higher specificities than using Thai healthy donors. Our findings suggest that antigen-specific ELISAs, particularly the OPS-ELISA, may be useful for serodiagnosis of melioidosis in areas where it is endemic and nonendemic.
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Affiliation(s)
- Vichaya Suttisunhakul
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Vanaporn Wuthiekanun
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Paul J Brett
- Department of Microbiology and Immunology, University of South Alabama, Mobile, Alabama, USA
| | - Srisin Khusmith
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Nicholas P J Day
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand Center for Tropical Medicine & Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Mary N Burtnick
- Department of Microbiology and Immunology, University of South Alabama, Mobile, Alabama, USA
| | - Direk Limmathurotsakul
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Narisara Chantratita
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
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Li D, March J, Bills T, Holt B, Wilson C, Lowe W, Tolley H, Lee M, Robison R. Gas chromatography-mass spectrometry method for rapid identification and differentiation of Burkholderia pseudomallei
and Burkholderia mallei
from each other, Burkholderia thailandensis
and several members of the Burkholderia cepacia
complex. J Appl Microbiol 2013; 115:1159-71. [DOI: 10.1111/jam.12310] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 07/07/2013] [Accepted: 07/18/2013] [Indexed: 10/26/2022]
Affiliation(s)
- D. Li
- Department of Chemistry and Biochemistry; Brigham Young University; Provo UT USA
| | - J.K. March
- Department of Microbiology and Molecular Biology; Brigham Young University; Provo UT USA
| | - T.M. Bills
- Department of Microbiology and Molecular Biology; Brigham Young University; Provo UT USA
| | - B.C. Holt
- Department of Statistics; Brigham Young University; Provo UT USA
| | - C.E. Wilson
- Department of Chemistry and Biochemistry; Brigham Young University; Provo UT USA
| | - W. Lowe
- Department of Microbiology and Molecular Biology; Brigham Young University; Provo UT USA
| | - H.D. Tolley
- Department of Statistics; Brigham Young University; Provo UT USA
| | - M.L. Lee
- Department of Chemistry and Biochemistry; Brigham Young University; Provo UT USA
| | - R.A. Robison
- Department of Microbiology and Molecular Biology; Brigham Young University; Provo UT USA
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Comparison of TaqMan PCR assays for detection of the melioidosis agent Burkholderia pseudomallei in clinical specimens. J Clin Microbiol 2012; 50:2059-62. [PMID: 22442327 DOI: 10.1128/jcm.06737-11] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Melioidosis is an emerging infectious disease caused by the soil bacterium Burkholderia pseudomallei. In diagnostic and forensic settings, molecular detection assays need not only high sensitivity with low limits of detection but also high specificity. In a direct comparison of published and newly developed TaqMan PCR assays, we found the TTS1-orf2 assay to be superior in detecting B. pseudomallei directly from clinical specimens. The YLF/BTFC multiplex assay (targeting the Yersinia-like fimbrial/Burkholderia thailandensis-like flagellum and chemotaxis region) also showed high diagnostic sensitivity and provides additional information on possible geographic origin.
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Evidence of Burkholderia pseudomallei-specific immunity in patient sera persistently nonreactive by the indirect hemagglutination assay. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2011; 18:1288-91. [PMID: 21677111 DOI: 10.1128/cvi.00077-11] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The indirect hemagglutination assay (IHA) is the most frequently used serological test to confirm exposure to Burkholderia pseudomallei. Patients with culture-confirmed disease often have a nonreactive IHA at presentation and occasionally fail to seroconvert on serial testing. We investigated whether using antigens derived from the cultured isolates of persistently IHA-nonreactive patient sera improved the sensitivity of the IHA. In addition, we assessed the antigen-specific lymphocyte response in this group of patients to a panel of B. pseudomallei antigens, including those derived from their own cultured isolates. Eleven patients with culture-proven melioidosis were identified as having persistently IHA-nonreactive sera. A modified IHA using erythrocytes sensitized with patient isolate-derived antigen tested against convalescent-phase serum was performed. The majority (82%) of sera showed a negative (≤ 1:5) result, one was borderline (1:20), and one was positive at the cutoff value (1:40). IHA-nonreactive sera were also tested by enzyme immunoassay (EIA), with 73% (8/11) demonstrating IgG positivity. In addition, lymphocytes isolated from persistently IHA-nonreactive patient sera demonstrated significantly increased proliferation in response to B. pseudomallei antigens compared to controls. These studies demonstrate the presence of B. pseudomallei-specific antibody by EIA and B. pseudomallei-specific lymphocytes in patient sera categorized as persistently nonreactive according to the IHA. New immunoassays are required and should incorporate B. pseudomallei antigens that are immunoreactive for this subset of IHA-nonreactive patient sera.
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Defining the true sensitivity of culture for the diagnosis of melioidosis using Bayesian latent class models. PLoS One 2010; 5:e12485. [PMID: 20830194 PMCID: PMC2932979 DOI: 10.1371/journal.pone.0012485] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Accepted: 08/09/2010] [Indexed: 11/23/2022] Open
Abstract
Background Culture remains the diagnostic gold standard for many bacterial infections, and the method against which other tests are often evaluated. Specificity of culture is 100% if the pathogenic organism is not found in healthy subjects, but the sensitivity of culture is more difficult to determine and may be low. Here, we apply Bayesian latent class models (LCMs) to data from patients with a single Gram-negative bacterial infection and define the true sensitivity of culture together with the impact of misclassification by culture on the reported accuracy of alternative diagnostic tests. Methods/Principal Findings Data from published studies describing the application of five diagnostic tests (culture and four serological tests) to a patient cohort with suspected melioidosis were re-analysed using several Bayesian LCMs. Sensitivities, specificities, and positive and negative predictive values (PPVs and NPVs) were calculated. Of 320 patients with suspected melioidosis, 119 (37%) had culture confirmed melioidosis. Using the final model (Bayesian LCM with conditional dependence between serological tests), the sensitivity of culture was estimated to be 60.2%. Prediction accuracy of the final model was assessed using a classification tool to grade patients according to the likelihood of melioidosis, which indicated that an estimated disease prevalence of 61.6% was credible. Estimates of sensitivities, specificities, PPVs and NPVs of four serological tests were significantly different from previously published values in which culture was used as the gold standard. Conclusions/Significance Culture has low sensitivity and low NPV for the diagnosis of melioidosis and is an imperfect gold standard against which to evaluate alternative tests. Models should be used to support the evaluation of diagnostic tests with an imperfect gold standard. It is likely that the poor sensitivity/specificity of culture is not specific for melioidosis, but rather a generic problem for many bacterial and fungal infections.
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Burkholderia pseudomallei infection in a cystic fibrosis patient from the Caribbean: a case report. Can Respir J 2008; 15:237-9. [PMID: 18716683 DOI: 10.1155/2008/290412] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Burkholderia pseudomallei is a pathogen identified with increasing frequency in the respiratory tracts of cystic fibrosis (CF) patients from endemic areas such as Southeast Asia and northern Australia. The following report describes the first known reported case in a CF patient from the Caribbean attending a North American CF clinic.
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11
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Cheng AC, Peacock SJ, Limmathurotsakul D, Wongsuvan G, Chierakul W, Amornchai P, Getchalarat N, Chaowagul W, White NJ, Day NPJ, Wuthiekanun V. Prospective evaluation of a rapid immunochromogenic cassette test for the diagnosis of melioidosis in northeast Thailand. Trans R Soc Trop Med Hyg 2005; 100:64-7. [PMID: 16168447 DOI: 10.1016/j.trstmh.2005.04.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2005] [Accepted: 04/08/2005] [Indexed: 11/22/2022] Open
Abstract
A prospective study was performed to compare a rapid immunochromogenic cassette test (ICT) with the indirect haemagglutination assay (IHA) and clinical rules for the diagnosis of melioidosis in an endemic area. The sensitivity and specificity of the IgG ICT was 86% and 47%, and the IgM ICT was 82% and 47%, respectively. These were similar to the results for IHA (sensitivity 73%, specificity 64%) and clinical rules (73% and 37%). ICT lacks clinical utility as a result of high background rates of positive Burkholderia pseudomallei serology in this population. Low sensitivity and specificity of clinical rules is consistent with the protean manifestations of melioidosis and clinical difficulty in identifying patients with melioidosis.
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Affiliation(s)
- Allen C Cheng
- Faculty of Tropical Medicine, Mahidol University, 420/6 Rajvithi Road, Bangkok, 10400, Thailand
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12
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Abstract
Melioidosis, caused by the gram-negative saprophyte Burkholderia pseudomallei, is a disease of public health importance in southeast Asia and northern Australia that is associated with high case-fatality rates in animals and humans. It has the potential for epidemic spread to areas where it is not endemic, and sporadic case reports elsewhere in the world suggest that as-yet-unrecognized foci of infection may exist. Environmental determinants of this infection, apart from a close association with rainfall, are yet to be elucidated. The sequencing of the genome of a strain of B. pseudomallei has recently been completed and will help in the further identification of virulence factors. The presence of specific risk factors for infection, such as diabetes, suggests that functional neutrophil defects are important in the pathogenesis of melioidosis; other studies have defined virulence factors (including a type III secretion system) that allow evasion of killing mechanisms by phagocytes. There is a possible role for cell-mediated immunity, but repeated environmental exposure does not elicit protective humoral or cellular immunity. A vaccine is under development, but economic constraints may make vaccination an unrealistic option for many regions of endemicity. Disease manifestations are protean, and no inexpensive, practical, and accurate rapid diagnostic tests are commercially available; diagnosis relies on culture of the organism. Despite the introduction of ceftazidime- and carbapenem-based intravenous treatments, melioidosis is still associated with a significant mortality attributable to severe sepsis and its complications. A long course of oral eradication therapy is required to prevent relapse. Studies exploring the role of preventative measures, earlier clinical identification, and better management of severe sepsis are required to reduce the burden of this disease.
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Affiliation(s)
- Allen C Cheng
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia
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13
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Cheng AC, Currie BJ. Melioidosis: epidemiology, pathophysiology, and management. Clin Microbiol Rev 2005. [PMID: 15831829 DOI: 10.1128/cmr.18.2.383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023] Open
Abstract
Melioidosis, caused by the gram-negative saprophyte Burkholderia pseudomallei, is a disease of public health importance in southeast Asia and northern Australia that is associated with high case-fatality rates in animals and humans. It has the potential for epidemic spread to areas where it is not endemic, and sporadic case reports elsewhere in the world suggest that as-yet-unrecognized foci of infection may exist. Environmental determinants of this infection, apart from a close association with rainfall, are yet to be elucidated. The sequencing of the genome of a strain of B. pseudomallei has recently been completed and will help in the further identification of virulence factors. The presence of specific risk factors for infection, such as diabetes, suggests that functional neutrophil defects are important in the pathogenesis of melioidosis; other studies have defined virulence factors (including a type III secretion system) that allow evasion of killing mechanisms by phagocytes. There is a possible role for cell-mediated immunity, but repeated environmental exposure does not elicit protective humoral or cellular immunity. A vaccine is under development, but economic constraints may make vaccination an unrealistic option for many regions of endemicity. Disease manifestations are protean, and no inexpensive, practical, and accurate rapid diagnostic tests are commercially available; diagnosis relies on culture of the organism. Despite the introduction of ceftazidime- and carbapenem-based intravenous treatments, melioidosis is still associated with a significant mortality attributable to severe sepsis and its complications. A long course of oral eradication therapy is required to prevent relapse. Studies exploring the role of preventative measures, earlier clinical identification, and better management of severe sepsis are required to reduce the burden of this disease.
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Affiliation(s)
- Allen C Cheng
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia
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