Prevalence of nontuberculous mycobacteria and high efficacy of D-cycloserine and its synergistic effect with clarithromycin against Mycobacterium fortuitum and Mycobacterium abscessus

Abstract Objective Infections due to nontuberculous mycobacteria (NTM) is increasing globally and may present as drug-resistant tuberculosis (DRTB). In India, data on NTM prevalence and species diversity is limited. Present study was conducted to detect the prevalence and profile of NTM among patients suspected of DRTB using paraffin slide culture (PSC)and mycobacteria growth indicator tube (MGIT) culture methods for isolation of NTM. Material and Method A total of 2,938 samples suspected of TB/DRTB were cultured on PSC and MGIT960. Species identification of mycobacterial isolate was done by sequencing of 16s ribosomal RNA gene. Result Among 2938 samples, 35 (1.19%) were found positive for NTM by PSC and 9 (0.30%) were found positive by MGIT. The diversity of NTM species was high (13 species). Out of 35 NTM isolates by PSC, maximum 34.29% (12) isolates were found to be Mycobacterium fortuitum, followed by 11.43% (4) Mycobacterium abscessus and Mycobacterium chelonae, and 42.85% (15) were other species viz. 8.57% (3) were Mycobacterium intracellulare and Mycobacterium kansasii, 5.71% (2) were Mycobacterium peregrinum, and 2.85% (1) were Mycobacterium flavescens, Mycobacterium farcinogenes, Mycobacterium moriokanese, Mycobacterium wolinskyi, Mycobacterium simiae, Mycobacterium goodii, and Mycobacterium terrae each. Coinfection of Mycobacterium tuberculosis(MTB) and NTM was found in 60% (21) samples. Conclusion Prevalence of NTM was low among multidrug resistant tuberculosis/TB suspected patients, similar to other studies done in India. PSC was found better than MGIT for the isolation of NTM, though poor separation of NTM and MTB on subculture may have led to false negativity in cases of coinfection. About 13 species were isolated; M. fortuitum was the most common of all. Since coinfection of NTM and TB can also occur, samples of patients suspected of NTM should be cultured on PSC even if positive for MTB.

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Species Typing of Nontuberculous Mycobacteria by Use of Deoxyribozyme Sensors

Clinical Chemistry ◽

10.1373/clinchem.2018.295212 ◽

2019 ◽

Vol 65 (2) ◽

pp. 333-341 ◽

Cited By ~ 2

Author(s):

Hillary N Wood ◽

Ashelyn E Sidders ◽

Lauren E Brumsey ◽

Evgeny S Morozkin ◽

Yulia V Gerasimova ◽

...

Keyword(s):

Nontuberculous Mycobacteria ◽

Point Of Care ◽

Pcr Amplification ◽

Rapid Identification ◽

Mycobacterium Abscessus ◽

Mycobacterium Fortuitum ◽

Target Sequence ◽

Proof Of Concept ◽

Catalytic Core ◽

Point Of Care Diagnostics

Abstract BACKGROUND Nontuberculous mycobacteria (NTM) species are a rising threat, especially to patients living with pulmonary comorbidities. Current point-of-care diagnostics fail to adequately identify and differentiate NTM species from Mycobacterium tuberculosis (Mtb). Definitive culture- and molecular-based testing can take weeks to months and requires sending samples out to specialized diagnostic laboratories. METHODS In this proof-of-concept study, we developed an assay based on PCR amplification of 16S ribosomal RNA (rRNA) rrs genes by using universal mycobacterial primers and interrogation of the amplified fragments with a panel of binary deoxyribozyme (BiDz) sensors to enable species-level identification of NTM (BiDz-NTMST). Each BiDz sensor consists of 2 subunits of an RNA-cleaving deoxyribozyme, which form an active deoxyribozyme catalytic core only in the presence of the complimentary target sequence. The target-activated BiDz catalyzes cleavage of a reporter substrate, thus triggering either fluorescent or colorimetric (visually observed) signal depending on the substrate used. The panel included BiDz sensors for differentiation of 6 clinically relevant NTM species (Mycobacterium abscessus, Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium fortuitum, Mycobacterium kansasii, and Mycobacterium gordonae) and Mtb. RESULTS Using the fluorescent BiDz-NTMST assay, we successfully identified the species of 38 clinical isolates. In addition, a subset of strains was tested with visual BiDz sensors, providing proof-of-concept for species typing of NTM by the naked eye. CONCLUSIONS The BiDz-NTMST assay is a novel platform for rapid identification of NTM species. This method is highly specific and significantly faster than current tools and is easily adaptable for onsite diagnostic laboratories in hospitals or clinical laboratories.

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The Changing Pattern of Nontuberculous Mycobacterial Disease

Canadian Journal of Infectious Diseases ◽

10.1155/2003/323058 ◽

2003 ◽

Vol 14 (5) ◽

pp. 281-286 ◽

Cited By ~ 48

Author(s):

Joseph O Falkinham

Keyword(s):

Pulmonary Disease ◽

Nontuberculous Mycobacteria ◽

Mycobacterial Infection ◽

Mycobacterium Abscessus ◽

Mycobacterium Fortuitum ◽

Older Individuals ◽

Mycobacterial Disease ◽

Cervical Lymphadenitis ◽

Source Of Infection ◽

Increased Risk

Nontuberculous mycobacteria are human opportunistic pathogens whose source of infection is the environment. These include both slow-growing (eg,Mycobacterium kansasii and Mycobacterium avium) and rapid-growing (eg,Mycobacterium abscessusandMycobacterium fortuitum) species. Transmission is through ingestion or inhalation of water, particulate matter or aerosols, or through trauma. The historic presentation of pulmonary disease in older individuals with predisposing lung conditions and in children has been changing. Pulmonary disease in elderly individuals who lack the classic predisposing lung conditions is increasing. Pulmonary disease and hypersensitivity pneumonitis have been linked with occupational or home exposures to nontuberculous mycobacteria. There has been a shift fromMycobacterium scrofulaceumtoM aviumin children with cervical lymphadenitis. Further, individuals who are immunosuppressed due to therapy or HIV-infection are at a greatly increased risk for nontuberculous mycobacterial infection. The changing pattern of nontuberculous mycobacterial disease is due in part to the ability of these pathogens to survive and proliferate in habitats that they share with humans, such as drinking water. The advent of an aging population and an increase in the proportion of immunosuppressed individuals suggest that the prevalence of nontuberculous mycobacterial disease will increase.

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In Vitro Activity of Bedaquiline against Nontuberculous Mycobacteria in China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02627-16 ◽

2017 ◽

Vol 61 (5) ◽

Cited By ~ 39

Author(s):

Yu Pang ◽

Huiwen Zheng ◽

Yaoju Tan ◽

Yuanyuan Song ◽

Yanlin Zhao

Keyword(s):

Molecular Mechanisms ◽

Nontuberculous Mycobacteria ◽

Mycobacterium Abscessus ◽

Dilution Method ◽

Mycobacterium Fortuitum ◽

Nucleotide Substitutions ◽

Content Type ◽

Prevalent Species ◽

Broth Dilution

ABSTRACT The main goal of our study was to evaluate the in vitro bedaquiline susceptibility of six prevalent species of pathogenic nontuberculous mycobacteria (NTM) in China. In addition, we investigated the potential molecular mechanisms contributing to bedaquiline resistance in the different NTM species. Among slowly growing mycobacteria (SGM), bedaquiline exhibited the highest activity against Mycobacterium avium; the MIC50 and MIC90 values were 0.03 and 16 mg/liter, respectively. Among rapidly growing mycobacteria (RGM), Mycobacterium abscessus subsp. abscessus (M. abscessus) and Mycobacterium abscessus subsp. massiliense (M. massiliense) seemed more susceptible to bedaquiline than Mycobacterium fortuitum, with MIC50 and MIC90 values of 0.13 and >16 mg/liter, respectively, for both species. On the basis of bimodal distributions of bedaquiline MICs, we proposed the following epidemiological cutoff (ECOFF) values: 1.0 mg/liter for SGM and 2.0 mg/liter for RGM. Among M. avium, Mycobacterium intracellulare, Mycobacterium kansasii, M. abscessus, M. massiliense, and M. fortuitum isolates, 14 (29.8%), 41 (27.2%), 33 (39.3%), 44 (20.2%), 42 (25.8%), and 7 (31.8%), respectively, were resistant to bedaquiline. No significant differences in the proportions of bedaquiline resistance among these species were observed (P > 0.05). Genetic mutations were observed in 74 isolates (10.8%), with all nucleotide substitutions being synonymous. In conclusion, our data demonstrate that bedaquiline shows moderate in vitro activity against NTM species. Using the proposed ECOFF values, we could distinguish between bedaquiline-resistant and -susceptible strains with the broth dilution method. In addition, no nonsynonymous mutations in the atpE gene that conferred bedaquiline resistance in all six NTM species were identified.

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Decontamination Strategies Used for AFB Culture Significantly Reduce the Viability of Mycobacterium abscessus Complex in Sputum Samples from Patients with Cystic Fibrosis

Microorganisms ◽

10.3390/microorganisms9081597 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1597

Author(s):

Dominic Stephenson ◽

Audrey Perry ◽

Andrew Nelson ◽

Ali E. Robb ◽

Matthew F. Thomas ◽

...

Keyword(s):

Cystic Fibrosis ◽

Oxalic Acid ◽

Nontuberculous Mycobacteria ◽

Optimal Recovery ◽

Mycobacterium Abscessus ◽

Colony Count ◽

Respiratory Pathogens ◽

Quantitative Culture ◽

Mycobacterium Abscessus Complex ◽

Oxalic Acids

Nontuberculous mycobacteria are important respiratory pathogens in patients with cystic fibrosis (CF). For diagnosis, international guidelines recommend culture of sputum that has been decontaminated via chemical treatment. Fifty-six sputum samples from 32 patients known to be previously colonized or infected with NTM were subdivided, and the aliquots were subjected to six different decontamination strategies, followed by quantitative culture for NTM. Thirty sputum samples contained Mycobacterium abscessus complex (MABSC) and 11 contained Mycobacterium avium complex (MAC). Decontamination strategies included treatment with N-acetyl L-cysteine with 2% sodium hydroxide (NALC-NaOH), 4% NaOH, 1% chlorhexidine, 0.5 N sulfuric acid, 5% oxalic acid, double decontamination with NALC-NaOH, followed by 5% oxalic acid, and saline (0.85%) as a control. The samples were also cultured directly with no treatment. Treatment with NALC-NaOH resulted in an average reduction in colony count of 87% for MABSC when compared with direct culture. NaOH at 4% caused a 98.3% average reduction in colony count. All treatments that included NaOH resulted in colony counts that were statistically lower than those obtained from direct culture or the saline-treated control (p < 0.05). Standard treatments using sulfuric or oxalic acids were less deleterious, but still resulted in an average reduction in colony count of at least 30%. The viability of MAC was much less affected by most decontamination treatments. In conclusion, the viability of MABSC was severely compromised by standard decontamination regimens. This supports recent evidence showing that optimal recovery of MABSC is achieved by culture on an appropriate selective agar without decontamination of sputum samples.

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Effective Treatment of Mycobacterium avium subsp. hominissuis and Mycobacterium abscessus Species Infections in Macrophages, Biofilm, and Mice by Using Liposomal Ciprofloxacin

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00440-18 ◽

2018 ◽

Vol 62 (10) ◽

Cited By ~ 9

Author(s):

James D. Blanchard ◽

Valerie Elias ◽

David Cipolla ◽

Igor Gonda ◽

Luiz E. Bermudez

Keyword(s):

Effective Treatment ◽

Mouse Models ◽

Mycobacterium Avium ◽

Nontuberculous Mycobacteria ◽

Mycobacterium Abscessus ◽

Content Type ◽

Number Of Individuals ◽

Intranasal Instillation

ABSTRACT Nontuberculous mycobacteria (NTM) affect an increasing number of individuals worldwide. Infection with these organisms is more common in patients with chronic lung conditions, and treatment is challenging. Quinolones, such as ciprofloxacin, have been used to treat patients, but the results have not been encouraging. In this report, we evaluate novel formulations of liposome-encapsulated ciprofloxacin (liposomal ciprofloxacin) in vitro and in vivo. Its efficacy against Mycobacterium avium and Mycobacterium abscessus was examined in macrophages, in biofilms, and in vivo using intranasal instillation mouse models. Liposomal ciprofloxacin was significantly more active than free ciprofloxacin against both pathogens in macrophages and biofilms. When evaluated in vivo, treatment with the liposomal ciprofloxacin formulations was associated with significant decreases in the bacterial loads in the lungs of animals infected with M. avium and M. abscessus. In summary, topical delivery of liposomal ciprofloxacin in the lung at concentrations greater than those achieved in the serum can be effective in the treatment of NTM, and further evaluation is warranted.

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A Current Microbiological Picture of Mycobacterium Isolates from Istanbul, Turkey

Polish Journal of Microbiology ◽

10.33073/pjm-2020-021 ◽

2020 ◽

Vol 69 (2) ◽

pp. 185-191

Author(s):

BILGE SUMBUL ◽

MEHMET ZIYA DOYMAZ

Keyword(s):

Multidrug Resistant ◽

Mycobacterium Abscessus ◽

Diagnostic Methods ◽

Current Status ◽

Clinical Samples ◽

Mycobacterium Fortuitum ◽

Mycobacterium Species ◽

Full Spectrum ◽

Number Of Patients ◽

Lowenstein Jensen

Despite advances in diagnosis and treatment, tuberculosis (TB) continues to be one of the essential health problems throughout the world. Turkey is considered to be endemic for TB. In this study, we analyzed the distribution of Mycobacterium species, compare the diagnostic methods, and susceptibilities to anti-tuberculosis drugs of TB isolates. The aim was to document the current status and to provide a frame of reference for future studies. In this study, 278 Mycobacterium species isolated from 7,480 patients between September 2015 and June 2019 were included. Löwenstein-Jensen medium (LJ) and MGIT 960 were used for the isolation of strains. Susceptibility to 1st-line anti-tuberculosis drugs was determined. Positivity rates in clinical samples were as follows: 1.4% for direct microscopic acid-fast bacilli (AFB) detection, 3.4% for growth on the LJ, and 3.7% for growth on MGIT-960. Two hundred thirty-three isolates were identified as Mycobacterium tuberculosis complex (MTBC) and 45 were non-tuberculous mycobacteria (NTMs). Eleven of the NTMs (24.4%) were Mycobacterium fortuitum group isolates, and eight NTMs (17.7%) were Mycobacterium abscessus complex isolates. A number of patients diagnosed with tuberculosis peaked twice between the ages of 20–31 and 60–71. A hundred and eighty-two MTBC isolates (78.1%) were susceptible to all 1st-line anti-tuberculosis drugs, while 51 isolates (21.9%) were resistant to at least one drug tested. The multidrug-resistant tuberculosis rate was 13.7% among resistant strains and 3% in all strains. The liquid cultures were better for detection of both MTBC and NTMs isolates. The data demonstrate that MTBC continues to be challenge for this country and indicates the need for continued surveillance and full-spectrum services of mycobacteriology laboratory and infectious diseases.

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Opportunist Coinfections by Nontuberculous Mycobacteria and Fungi in Immunocompromised Patients

Antibiotics ◽

10.3390/antibiotics9110771 ◽

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.

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In Vitro Susceptibility of Mycobacterium abscessus and Mycobacterium fortuitum Isolates to 30 Antibiotics

BioMed Research International ◽

10.1155/2018/4902941 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Yaojie Shen ◽

Xuyang Wang ◽

Jialin Jin ◽

Jing Wu ◽

Xuelian Zhang ◽

...

Keyword(s):

Public Health Problem ◽

Drug Susceptibility ◽

Mycobacterium Abscessus ◽

Mycobacterium Fortuitum ◽

In Vitro Susceptibility ◽

Antitubercular Drugs ◽

Microdilution Method ◽

Susceptibility Tests ◽

Susceptibility Profiles

Objective. Nontuberculous mycobacteria (NTM) cause various diseases in humans and animals. Recently, the prevalence of NTM-related disease has been on the rise, becoming an emerging public health problem. The aim of this study was to determine the antibiotic susceptibility profiles of clinical isolates of Mycobacterium abscessus and Mycobacterium fortuitum. Methods. We performed susceptibility tests on 37 clinical NTM isolates to 30 antibiotics with the microdilution method recommended by the Clinical and Laboratory Standards Institute. Results. Both M. abscessus and M. fortuitum were highly resistant to antitubercular drugs such as isoniazid, rifampin, ethambutol, clofazimine, ethionamide, and rifabutin. M. abscessus showed the lowest resistant rates to cefoxitin (10%), azithromycin (10%), amikacin (10%), and clarithromycin (20%) and very high resistant to sulfamethoxazole, vancomycin, oxacillin, clindamycin, and all fluoroquinolones. M. fortuitum showed low resistance to tigecycline (0%), tetracycline (0%), cefmetazole (12%), imipenem (12%), linezolid (18%), and the aminoglycosides amikacin (0%), tobramycin (0%), neomycin (0%), and gentamycin (24%). Conclusion. Amikacin, cefoxitin, and azithromycin have the highest in vitro activity against M. abscessus. Isolates of M. fortuitum need to be individually evaluated for drug susceptibility before choosing an effective antimicrobial regimen for treatment of infections.

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