scholarly journals Cas12a/Guide RNA-Based Platform for Rapid and Accurate Identification of Major Mycobacterium Species

2019 ◽  
Vol 58 (2) ◽  
Author(s):  
Guohui Xiao ◽  
Xing He ◽  
Su Zhang ◽  
Yaya Liu ◽  
Zhihang Liang ◽  
...  
Keyword(s):  
Clinical Symptoms ◽  
Cost Effective ◽  
Cross Reactivity ◽  
Mycobacterium Abscessus ◽  
Mycobacterium Fortuitum ◽  
Accurate Identification ◽  
Content Type ◽  
Guide Rna ◽  
Promising Tool ◽  
Species Specific

ABSTRACT Mycobacterium tuberculosis infection and nontuberculous mycobacteria (NTM) infections exhibit similar clinical symptoms; however, the therapies for these two types of infections are different. Therefore, the rapid and accurate identification of M. tuberculosis and NTM species is very important for the control of tuberculosis and NTM infections. In the present study, a Cas12a/guide RNA (gRNA)-based platform was developed to identify M. tuberculosis and most NTM species. By designing species-specific gRNA probes targeting the rpoB sequence, a Cas12a/gRNA-based platform successfully identified M. tuberculosis and six major NTM species (Mycobacterium abscessus, Mycobacterium intracellulare, Mycobacterium avium, Mycobacterium kansasii, Mycobacterium gordonae, and Mycobacterium fortuitum) without cross-reactivity. In a blind assessment, a total of 72 out of 73 clinical Mycobacterium isolates were correctly identified, which is consistent with previous rpoB sequencing results. These results suggest that the Cas12a/gRNA-based platform is a promising tool for the rapid, accurate, and cost-effective identification of both M. tuberculosis and NTM species.

scholarly journals Opportunist Coinfections by Nontuberculous Mycobacteria and Fungi in Immunocompromised Patients

Antibiotics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 771
Author(s):  
Ines Joao ◽  
Helena Bujdáková ◽  
Luisa Jordao
Keyword(s):  
Histoplasma Capsulatum ◽  
Opportunistic Infections ◽  
Clinical Symptoms ◽  
Nontuberculous Mycobacteria ◽  
Wide Spectrum ◽  
Case Reports ◽  
Fungal Species ◽  
Mycobacterium Abscessus ◽  
Accurate Identification ◽  
Patient Prognosis

Nontuberculous mycobacteria (NTM) and many fungal species (spp.) are commonly associated with opportunistic infections (OPIs) in immunocompromised individuals. Moreover, occurrence of concomitant infection by NTM (mainly spp. of Mycobacterium avium complex and Mycobacterium abscessus complex) and fungal spp. (mainly, Aspergillus fumigatus, Histoplasma capsulatum and Cryptococcus neoformans) is very challenging and is associated with poor patient prognosis. The most frequent clinical symptoms for coinfection and infection by single agents (fungi or NTM) are similar. For this reason, the accurate identification of the aetiological agent(s) is crucial to select the best treatment approach. Despite the significance of this topic it has not been sufficiently addressed in the literature. This review aims at summarizing case reports and studies on NTM and fungi coinfection during the last 20 years. In addition, it briefly characterizes OPIs and coinfection, describes key features of opportunistic pathogens (e.g., NTM and fungi) and human host predisposing conditions to OPIs onset and outcome. The review could interest a wide spectrum of audiences, including medical doctors and scientists, to improve awareness of these infections, leading to early identification in clinical settings and increasing research in the field. Improved diagnosis and availability of therapeutic options might contribute to improve the prognosis of patients’ survival.

scholarly journals GenSeizer: A Multiplex PCR-Based Targeted Gene Sequencing Platform for Rapid and Accurate Identification of Major Mycobacterium Species

2020 ◽  
Author(s):  
Bing Li ◽  
Liyun Xu ◽  
Qi Guo ◽  
Jianhui Chen ◽  
Yanan Zhang ◽  
...  
Keyword(s):  
Multiplex Pcr ◽  
Clinical Symptoms ◽  
Simultaneous Detection ◽  
Gene Sequencing ◽  
Large Data ◽  
Cross Reactivity ◽  
Accurate Identification ◽  
Data Set ◽  
Sequencing Platform ◽  
Targeted Gene Sequencing

Mycobacterium tuberculosis (MTB) and non-tuberculous mycobacteria (NTM) infections often exhibit similar clinical symptoms. Timely and effective treatment relies on the rapid and accurate identification of species and resistance genotypes. In this study, a new platform (GenSeizer), which combines bioinformatics analysis of a large data set and multiplex PCR-based targeted gene sequencing, was developed to identify 10 major Mycobacterium species that cause pulmonary, as well as extrapulmonary, human diseases. Simultaneous detection of certain resistance erm(41) and rrl genotypes in M. abscessus was also feasible. This platform was specific and sensitive, exhibited no cross-reactivity among reference strains and a detection limit of 5 DNA copies or 50 CFU Mycobacterium/ml. In a blinded comparison, GenSeizer and multigene sequencing showed 100% agreement in the ability to identify 88 clinical, Mycobacterium isolates. The resistance genotypes, confirmed by whole genome sequencing of 30 M. abscessus strains, were also correctly identified by GenSeizer 100% of the time. These results indicate that GenSeizer is an efficient, reliable platform for diagnosing major pathogenic Mycobacterium species.

scholarly journals Performance assessment of a multi-epitope chimeric antigen for the serological diagnosis of acute Mayaro fever

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Paloma Napoleão-Pêgo ◽  
Flávia R. G. Carneiro ◽  
Andressa M. Durans ◽  
Larissa R. Gomes ◽  
Carlos M. Morel ◽  
...  
Keyword(s):  
High Performance ◽  
Clinical Symptoms ◽  
Chimeric Protein ◽  
Cross Reactivity ◽  
Effective Control ◽  
Antigenic Determinants ◽  
Gene Encoding ◽  
Accurate Identification ◽  
Serological Tests ◽  
Mayaro Virus

AbstractMayaro virus (MAYV), which causes mayaro fever, is endemic to limited regions of South America that may expand due to the possible involvement of Aedes spp. mosquitoes in its transmission. Its effective control will require the accurate identification of infected individuals, which has been restricted to nucleic acid-based tests due to similarities with other emerging members of the Alphavirus genus of the Togaviridae family; both in structure and clinical symptoms. Serological tests have a more significant potential to expand testing at a reasonable cost, and their performance primarily reflects that of the antigen utilized to capture pathogen-specific antibodies. Here, we describe the assembly of a synthetic gene encoding multiple copies of antigenic determinants mapped from the nsP1, nsP2, E1, and E2 proteins of MAYV that readily expressed as a stable chimeric protein in bacteria. Its serological performance as the target in ELISAs revealed a high accuracy for detecting anti-MAYV IgM antibodies. No cross-reactivity was observed with serum from seropositive individuals for dengue, chikungunya, yellow fever, Zika, and other infectious diseases as well as healthy individuals. Our data suggest that this bioengineered antigen could be used to develop high-performance serological tests for MAYV infections.

scholarly journals Expression and Purification along with Evaluation of Serological Response and Diagnostic Potential of Recombinant Sap2 Protein from C. parapsilosis for Use in Systemic Candidiasis

2021 ◽  
Vol 7 (12) ◽  
pp. 999
Author(s):  
Manisha Shukla ◽  
Pankaj Chandley ◽  
Harsimran Kaur ◽  
Anup K. Ghosh ◽  
Shivaprakash M. Rudramurthy ◽  
...  
Keyword(s):  
Clinical Symptoms ◽  
Expression System ◽  
Cost Effective ◽  
Cross Reactivity ◽  
Serological Response ◽  
Systemic Candidiasis ◽  
E Coli ◽  
Diagnostic Potential ◽  
Prokaryotic Expression System ◽  
Secreted Aspartyl Proteinase

Systemic candidiasis is the fourth most common bloodstream infection in ICU patients worldwide. Although C. albicans is a predominant species causing systemic candidiasis, infections caused by non-albicans Candida (NAC) species are increasingly becoming more prevalent globally along with the emergence of drug resistance. The diagnosis of systemic candidiasis is difficult due to the absence of significant clinical symptoms in patients. We investigated the diagnostic potential of recombinant secreted aspartyl proteinase 2 (rSap2) from C. parapsilosis for the detection of Candida infection. The rSap2 protein was successfully cloned, expressed and purified using Ni-NTA chromatography under denaturing conditions using an E. coli-based prokaryotic expression system, and refolded using a multi-step dialysis procedure. Structural analysis by CD and FTIR spectroscopy revealed the refolded protein to be in its near native conformation. Immunogenicity analysis demonstrated the rSap2 protein to be highly immunogenic as evident from significantly high titers of Sap2-specific antibodies in antigen immunized Balb/c mice, compared to sham-immunized controls. The diagnostic potential of rSap2 protein was evaluated using immunoblotting and ELISA assays using proven candidiasis patient serum and controls. Immunoblotting results indicate that reactivity to rSap2 was specific to candidiasis patient sera with no cross reactivity observed in healthy controls. Increased levels of anti-Sap2-specific Ig, IgG and IgM antibodies were observed in candidiasis patients compared to controls and was similar in sensitivity obtained when whole Candida was used as coating antigen. In summary, the rSap2 protein from C. parapsilosis has the potential to be used in the diagnosis of systemic candidiasis, providing a rapid, convenient, accurate and cost-effective strategy.

Development of a nucleic acid chromatography assay for the detection of commonly isolated rapidly growing mycobacteria

2021 ◽  
Vol 70 (12) ◽  
Author(s):  
Yuriko Igarashi ◽  
Kinuyo Chikamatsu ◽  
Sotaro Sano ◽  
Shigehiko Miyamoto ◽  
Akio Aono ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Type Species ◽  
Target Genes ◽  
Mycobacterium Abscessus ◽  
Heat Denaturation ◽  
Mycobacterium Fortuitum ◽  
Mycobacterium Chelonae ◽  
Content Type ◽  
Rapidly Growing Mycobacteria ◽  
Link Type

Introduction. Non-tuberculosis mycobacterium infections are increasing worldwide, including those caused by rapidly growing mycobacteria (RGM). Gap Statement. The identification of the aetiological agent in the context of infections is essential for the adoption of an adequate therapeutic approach. However, the methods for the rapid distinction of different RGM species are less than optimal. Aim. To develop a nucleic acid chromatography kit to identify clinically common RGM. Methodology. We tried to develop a nucleic acid chromatography kit designed to detect four RGM species (including three subspecies) i.e. Mycobacterium abscessus subsp. abscessus , Mycobacterium abscessus subsp. bolletii (detected as M. abscessus/bolletii) Mycobacterium abscessus subsp. massiliense , Mycobacterium fortuitum , Mycobacterium chelonae and Mycobacterium peregrinum . The amplified target genes for each species/subspecies using multiplex PCR were analysed using a nucleic acid chromatography assay. Results. Among the 159 mycobacterial type strains and 70 RGM clinical isolates tested, the developed assay correctly identified all relevant RGM without any cross-reactivity or false-negatives. The limits of detection for each species were approximately 0.2 pg µl-1. Conclusion. The rapid and simple nucleic acid chromatography method developed here, which does not involve heat denaturation, may contribute to the rapid identification and treatment of RGM infections.

scholarly journals Defining Species-Specific Immunodominant B Cell Epitopes for Molecular Serology of Chlamydia Species

2015 ◽  
Vol 22 (5) ◽  
pp. 539-552 ◽  
Author(s):  
K. Shamsur Rahman ◽  
Erfan U. Chowdhury ◽  
Anil Poudel ◽  
Anke Ruettger ◽  
Konrad Sachse ◽  
...  
Keyword(s):  
B Cell ◽  
Cell Epitope ◽  
Cross Reactivity ◽  
Microbial Pathogens ◽  
B Cell Epitopes ◽  
Content Type ◽  
Peptide Antigens ◽  
Sequence Identity ◽  
B Cell Epitope ◽  
Species Specific

ABSTRACTUrgently needed species-specific enzyme-linked immunosorbent assays (ELISAs) for the detection of antibodies againstChlamydiaspp. have been elusive due to high cross-reactivity of chlamydial antigens. To identifyChlamydiaspecies-specific B cell epitopes for such assays, we ranked the potential epitopes of immunodominant chlamydial proteins that are polymorphic among allChlamydiaspecies. High-scoring peptides were synthesized with N-terminal biotin, followed by a serine-glycine-serine-glycine spacer, immobilized onto streptavidin-coated microtiter plates, and tested with mono-specific mouse hyperimmune sera against eachChlamydiaspecies in chemiluminescent ELISAs. For each of nineChlamydiaspecies, three to nine dominant polymorphic B cell epitope regions were identified on OmpA, CT618, PmpD, IncA, CT529, CT442, IncG, Omp2, TarP, and IncE proteins. Peptides corresponding to 16- to 40-amino-acid species-specific sequences of these epitopes reacted highly and with absolute specificity with homologous, but not heterologous,Chlamydiamonospecies-specific sera. Host-independent reactivity of such epitopes was confirmed by testing of sixC. pecorum-specific peptides from five proteins withC. pecorum-reactive sera from cattle, the natural host ofC. pecorum. The probability of cross-reactivity of peptide antigens from closely related chlamydial species or strains correlated with percent sequence identity and declined to zero at <50% sequence identity. Thus, phylograms of B cell epitope regions predict the specificity of peptide antigens for rational use in the genus-, species-, or serovar-specific molecular serology ofChlamydiaspp. We anticipate that these peptide antigens will improve chlamydial serology by providing easily accessible assays to nonspecialist laboratories. Our approach also lends itself to the identification of relevant epitopes of other microbial pathogens.

scholarly journals Molecular Mechanisms of Intrinsic Streptomycin Resistance in Mycobacterium abscessus

2017 ◽  
Vol 62 (1) ◽  
Author(s):  
Michael Dal Molin ◽  
Myriam Gut ◽  
Anna Rominski ◽  
Klara Haldimann ◽  
Katja Becker ◽  
...  
Keyword(s):  
Deletion Mutant ◽  
Molecular Mechanisms ◽  
Gene Deletion ◽  
Opportunistic Pathogen ◽  
Mycobacterium Abscessus ◽  
Streptomycin Resistance ◽  
Resistance Determinant ◽  
Mycobacterium Fortuitum ◽  
Content Type ◽  
Targeted Deletion

ABSTRACTStreptomycin, the first drug used for the treatment of tuberculosis, shows limited activity against the highly resistant pathogenMycobacterium abscessus. We recently identified two aminoglycoside-acetylating genes [aac(2′)andeis2] which, however, do not affect susceptibility to streptomycin. This suggests the existence of a discrete mechanism of streptomycin resistance.M. abscessusBLASTP analysis identified MAB_2385 as a close homologue of the 3″-O-phosphotransferase [APH(3″)] from the opportunistic pathogenMycobacterium fortuitumas a putative streptomycin resistance determinant. Heterologous expression ofMAB_2385inMycobacterium smegmatisincreased the streptomycin MIC, while the gene deletion mutantM. abscessusΔMAB_2385 showed increased streptomycin susceptibility. The MICs of other aminoglycosides were not altered inM. abscessusΔMAB_2385. This demonstrates thatMAB_2385encodes a specific and prime innate streptomycin resistance determinant inM. abscessus. We further explored the feasibility of applyingrpsL-based streptomycin counterselection to generate gene deletion mutants inM. abscessus. Spontaneous streptomycin-resistant mutants ofM. abscessusΔMAB_2385 were selected, and we demonstrated that the wild-typerpsLis dominant over the mutatedrpsLK43Rin merodiploid strains. In a proof of concept study, we exploited this phenotype for construction of a targeted deletion mutant, thereby establishing anrpsL-based counterselection method inM. abscessus.

scholarly journals Mycobacterium abscessus WhiB7 Regulates a Species-Specific Repertoire of Genes To Confer Extreme Antibiotic Resistance

2017 ◽  
Vol 61 (11) ◽  
Author(s):  
Kelley Hurst-Hess ◽  
Paulami Rudra ◽  
Pallavi Ghosh
Keyword(s):  
Antibiotic Resistance ◽  
Mycobacterium Abscessus ◽  
Specific Pattern ◽  
Lung Damage ◽  
Nontuberculous Mycobacterium ◽  
Content Type ◽  
Bronchopulmonary Infection ◽  
Typical Treatment ◽  
Species Specific ◽  
Cure Rates

ABSTRACT Mycobacterium abscessus causes acute and chronic bronchopulmonary infection in patients with chronic lung damage, of which cystic fibrosis (CF) patients are particularly vulnerable. The major threat posed by this organism is its high intrinsic antibiotic resistance. A typical treatment regimen involves a 6- to 12-month-long combination therapy of clarithromycin and amikacin, with cure rates below 50% and multiple side effects, especially due to amikacin. In the present work, we show that M. abscessus whiB7, a homologue of Mycobacterium tuberculosis and Mycobacterium smegmatis whiB7 with previously demonstrated effects on intrinsic antibiotic resistance, is strongly induced when exposed to clinically relevant antibiotics that target the ribosome: erythromycin, clarithromycin, amikacin, tetracycline, and spectinomycin. The deletion of M. abscessus whiB7 results in sensitivity to all of the above-mentioned antibiotics. Further, we have defined and compared the whiB7 regulon of M. abscessus with the closely related nontuberculous mycobacterium (NTM) M. smegmatis to demonstrate the induction of a species-specific repertoire of genes. Finally, we show that one such gene, eis2, is specifically induced in M. abscessus by whiB7 and contributes to its higher levels of intrinsic amikacin resistance. This species-specific pattern of gene induction might account for the differences in drug susceptibilities to other antibiotics and between different mycobacterial species.

scholarly journals Discovery of Human-Specific ImmunodominantChlamydia trachomatisB Cell Epitopes

mSphere ◽  
2018 ◽  
Vol 3 (4) ◽  
Author(s):  
K. Shamsur Rahman ◽  
Toni Darville ◽  
Ali N. Russell ◽  
Catherine M. O’Connell ◽  
Harold C. Wiesenfeld ◽  
...  
Keyword(s):  
B Cell ◽  
Cross Reactivity ◽  
Mouse Serum ◽  
Human Populations ◽  
Specific Detection ◽  
B Cell Epitopes ◽  
Content Type ◽  
Human Host ◽  
Peptide Antigens ◽  
Species Specific

ABSTRACTChlamydiaspecies-specific serology is compromised by cross-reactivity of the gold standard microimmunofluorescence (MIF) or commercial enzyme-linked immunosorbent assays (ELISAs). This study was conducted to discover novelC. trachomatis-specific peptide antigens that were recognized only by the antibody response of the natural human host. We evaluated a library of 271 peptide antigens from immunodominantC. trachomatisproteins by reactivity with 125C. trachomatisantibody-positive sera from women with PCR-confirmedC. trachomatisinfection and 17C. trachomatisantibody-negative sera from low-risk women never diagnosed withC. trachomatisinfection. TheseC. trachomatispeptide antigens had been predictedin silicoto contain B cell epitopes but had been nonreactive with mouse hyperimmune sera againstC. trachomatis. We discovered 38 novel human host-dependent antigens from 20 immunodominantC. trachomatisproteins (PmpD, IncE, IncG, CT529, CT618, CT442, TarP, CT143, CT813, CT795, CT223, PmpC, CT875, CT579, LcrE, IncA, CT226, CT694, Hsp60, and pGP3). Using these human sera, we also confirmed 10C. trachomatisB cell epitopes from 6 immunodominantC. trachomatisproteins (OmpA, PmpD, IncE, IncG, CT529, and CT618) as host species-independent epitopes that had been previously identified by their reactivity with mouse hyperimmune sera againstC. trachomatis. ELISA reactivities against these peptides correlated strongly with theC. trachomatismicroimmunofluorescence (MIF) text results (Pearson’s correlation coefficient [R] = 0.80;P< 10−6). TheseC. trachomatispeptide antigens do not cross-react with antibodies against otherChlamydiaspecies and are therefore suitable for species-specific detection of antibodies againstC. trachomatis. This study identified an extended set of peptide antigens for simpleC. trachomatis-specific ELISA serology.IMPORTANCECurrent serological assays for species-specific detection of anti-Chlamydiaspecies antibodies suffer from well-known shortcomings in specificity and ease of use. Due to the high prevalences of both anti-C. trachomatisand anti-C. pneumoniaeantibodies in human populations, species-specific serology is unreliable. Therefore, novel specific and simple assays for chlamydial serology are urgently needed. Conventional antigens are problematic due to extensive cross-reactivity withinChlamydiaspp. Using accurate B cell epitope prediction and a robust peptide ELISA methodology developed in our laboratory, we identified immunodominantC. trachomatisB cell epitopes by screening performed with sera fromC. trachomatis-infected women. We discovered 38 novel human host-dependent antigens from 20 immunodominantC. trachomatisproteins, in addition to confirming 10 host-independent mouse serum peptide antigens that had been identified previously. This extended set of highly specificC. trachomatispeptide antigens can be used in simple ELISA or multiplexed microarray formats and will provide high specificity and sensitivity to humanC. trachomatisserodiagnosis.

scholarly journals Non-tuberculous mycobacteria isolated from patients with suspected tuberculosis in Abidjan, Ivory Coast

2021 ◽  
Vol 22 (2) ◽  
pp. 304-309
Author(s):  
T. Ouassa ◽  
M.S. N’Guessan-Kacou ◽  
K.A. Kouakou
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Ivory Coast ◽  
Rapid Test ◽  
Mycobacterium Abscessus ◽  
University Hospital ◽  
Mycobacterium Fortuitum ◽  
Molecular Method ◽  
Test Reaction ◽  
Accurate Identification ◽  
Lowenstein Jensen

Background: Apart from tuberculosis caused by Mycobacterium tuberculosis complex (MTBc) species, there are many other  mycobacterial infections due to nontuberculous mycobacteria (NTM). These are rarely identified in many low resource settings in Africa because of the lack of accurate identification methods. The aim of the study is to identify NTM species involved in respiratory infections in Abidjan, Ivory Coast.Methodology: Isolates routinely identified as NTM by the detection of MPT64 antigen between 2015 and 2018 at the Centre for Diagnosis and Research on AIDS and other Infectious Diseases (CeDReS) of the University Hospital of Treichville, were included in the study. Bacterial strains were sub-cultured on three different Lowenstein-Jensen media in order to determine their cultural characteristics, and molecular identification of the strains was performed first by polymerase chain reaction (PCR) assay followed by reverse hybridization (GenoType Mycobacterium CM and AS kits, Hain Lifescience, Germany). The Cohen’s kappa statistical coefficientwas used to evaluate the degree of agreement of the phenotypic with the molecular method.Results: Of 62 NTM isolates tested with the molecular method, 54 (87.1%) tested positive and the main species identified were Mycobacterium fortuitum (52%), followed by Mycobacterium abscessus (13%) alone or in combination with other species. Thirty-six (58.1%) of the 62 NTM isolates were identified phenotypically, out of which 31 (86.1%) were correctly identified by molecular method. The comparison of molecular and phenotypic methods revealed a good concordance, allowing the use of cultural patterns as identification tests in resource limited settings. However, MTBc isolates were identified among the NTM isolates, indicating that even if the rapid test for detection of MPT64 antigen is quite accurate, it could lack sensitivity and specificity in some cases.Conclusion: Mycobacterium fortuitum and M. abscessus were identified as the main NTM species circulating in Abidjan but there is need for additional evaluation of MPT64 antigen detection assay for MTBc. Keywords: non-tuberculous mycobacteria, identification, PCR, GenoType CM/AS, culture   French Title: Mycobactéries non tuberculeuses isolées chez des patients suspects de tuberculose à Abidjan, Côte d'Ivoire Contexte: Outre la tuberculose causée par les espèces du complexe Mycobacterium tuberculosis (MTBc), il existe de nombreuses autres infections mycobactériennes dues à des mycobactéries non tuberculeuses (MNT). Ceux-ci sont rarement identifiés dans de nombreuses régions à ressources limitées, notamment en Afrique en raison du manque de méthodes d'identification précises. Le but de l'étude était d'identifier les espèces de MNT impliquées dans les infections respiratoires à Abidjan, en Côte d'Ivoire.Méthodologie: Des isolats identifiés en routine comme étant des MNT par la détection de l'antigène MPT64 entre  Non-tuberculous mycobacteria in Ivory Coast  2015 et 2018 au Centre de diagnostic et de recherche sur le sida et autres maladies infectieuses (CeDReS) sis au sein du CHU de Treichville, ont été inclus dans l'étude. Les souches bactériennes ont été réisolées sur trois milieux de Lowenstein-Jensen différents afin de déterminer leurs caractéristiques culturales, et l'identification moléculaire des souches a d'abord été réalisée par un test réaction de polymérisation en chaîne (PCR) suivi d'une hybridation inverse (kits GenoType Mycobacterium CM et AS, Hain Lifescience, Allemagne). Le test statistique kappa de Cohen a été utilisé pour évaluer le degré d’accord entre le phénotype et la méthode moléculaire.Résultats: Sur 62 isolats de NTM testés avec la méthode moléculaire, 54 (87,1%) ont été trouvés positifs les principales espèces identifiées étant Mycobacterium fortuitum (52%), suivi de Mycobacterium abscessus (13%) seul ou en association avec d'autres espèces. Trente-six (58,1%) des 62 isolats de MNT ont été identifiés phénotypiquement, parmi lesquels 31 (86,1%) ont été correctement identifiés par la méthode moléculaire. La comparaison des méthodes moléculaires et phénotypiques a révélé une bonne concordance, permettant l'utilisation de caractères culturaux comme tests d'orientation dans des zones à ressources limitées. Cependant, des isolats de MTBc ont été identifiés parmi les isolats de MNT, indiquant que même si le test rapide de détection de l'antigène MPT64 est assez précis, il pourrait manquer de sensibilité et de spécificité dans certains cas. Conclusion: Mycobacterium fortuitum et M. abscessus ont été identifiés comme les principales espèces de MNT circulant à Abidjan mais il est nécessaire de procéder à une évaluation supplémentaire du test de détection de l'antigène MPT64 pour l'identification des MTBc. Mots clés: mycobactéries non tuberculeuses, identification, PCR, GenoType CM/AS, culture

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