Comparison of Culture Methods for Isolation of Nontuberculous Mycobacteria from Surface Waters

ABSTRACT The environment is the likely source of most nontuberculous mycobacteria (NTM) involved in human infections, especially pulmonary, skin, and soft tissue infections. In order to measure the prevalence of NTM in different aquatic ecosystems, we tried to standardize the culture methods used for surface water testing since many procedures have been described previously. Cultivation of mycobacteria requires long-term incubation in rich media and inactivation of rapidly growing microorganisms whose growth impedes observation of mycobacterial colonies. Consequently, the two criteria used for evaluation of the methods examined were (i) the rate of inhibition of nontarget microorganisms and (ii) the efficiency of recovery of mycobacteria. We compared the competitive growth of Mycobacterium chelonae and M. avium with nontarget microorganisms on rich Middlebrook 7H11-mycobactin medium after treatment by several chemical decontamination methods that included acids, bases, detergent, or cetylpyridinium chloride (CPC) with and without an antibiotic cocktail, either PANTA (40 U/ml polymyxin, 4 μg/ml amphotericin B, 16 μg/ml nalidixic acid, 4 μg/ml trimethoprim, and 4 μg/ml azlocillin) or PANTAV (PANTA plus 10 μg/ml vancomycin). Our results showed that treatment for 30 min with CPC (final concentration, 0.05%) of water concentrated by centrifugation, followed by culture on a rich medium supplemented with PANTA, significantly decreased the growth of nontarget microorganisms (the concentrations were 6.2 Ã¯Â¿Â½ 0.4 log10 CFU/liter on Middlebrook 7H11j medium and 4.2 Ã¯Â¿Â½ 0.2 log10 CFU/liter on Middlebrook 7H11j medium containing PANTA [P < 0.001]), while the effect of this procedure on NTM was not as great (the concentrations of M. chelonae on the two media were 7.0 Ã¯Â¿Â½ 0.0 log10 CFU/liter and 6.9 Ã¯Â¿Â½ 0.0 log10 CFU/liter, respectively, and the concentrations of M. avium were 9.1 Ã¯Â¿Â½ 0.0 log10 CFU/liter and 8.9 Ã¯Â¿Â½ 0.0 log10 CFU/liter, respectively). We propose that this standardized culture procedure could be used for detection of NTM in aquatic samples.

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Profile of Nontuberculous Mycobacteria in Patients Suspected of Tuberculosis and Drug-Resistant Tuberculosis

Journal of Laboratory Physicians ◽

10.1055/s-0040-1721160 ◽

2020 ◽

Vol 12 (03) ◽

pp. 203-211

Author(s):

Megha Sharma ◽

Bharti Malhotra ◽

Jitendra Tiwari ◽

Shipra Bhargava

Keyword(s):

Nontuberculous Mycobacteria ◽

Multidrug Resistant ◽

Mycobacterium Abscessus ◽

Mycobacterium Fortuitum ◽

Drug Resistant ◽

Culture Methods ◽

Mycobacterium Chelonae ◽

Drug Resistant Tuberculosis ◽

Indicator Tube ◽

Resistant Tuberculosis

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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Long-term survival of Streptococcus pyogenes in rich media is pH-dependent

Microbiology ◽

10.1099/mic.0.054478-0 ◽

2012 ◽

Vol 158 (6) ◽

pp. 1428-1436 ◽

Cited By ~ 4

Author(s):

Dragutin J. Savic ◽

William M. McShan

Keyword(s):

Streptococcus Pyogenes ◽

Term Survival ◽

Long Term Survival ◽

Rich Media ◽

Ph Dependent

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DisseminatedMycobacterium chelonaeInfection Presenting as Progressive Multifocal Osteomyelitis: Report of Two Cases and a Review of the Literature

Canadian Journal of Infectious Diseases ◽

10.1155/1994/801012 ◽

1994 ◽

Vol 5 (1) ◽

pp. 28-32 ◽

Cited By ~ 5

Author(s):

David A Oelberg ◽

Jack Mendelson ◽

Mark A Miller ◽

Andre Dascal

Keyword(s):

Hospitalized Patients ◽

Review Of The Literature ◽

Mycobacterium Chelonae ◽

Bony Destruction ◽

Osseous Involvement ◽

Multifocal Osteomyelitis

Two long term hospitalized patients developed disseminated infections caused byMycobacterium chelonae,subspecies chelonae, over an eight-month period. In both cases, the disease was characterized by cutaneous and osseous involvement. The infections were indolent and marked by progressive bony destruction. These cases and a review of the literature are presented.

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Effect of on-farm interventions in the aftermath of an outbreak of hypervirulent verocytotoxin-producing Escherichia coli O157:H7 in Sweden

Veterinary Record ◽

10.1136/vr.104223 ◽

2018 ◽

Vol 182 (18) ◽

pp. 516-516 ◽

Cited By ~ 1

Author(s):

Lena-Mari Tamminen ◽

Helena Fransson ◽

Madeleine Tråvén ◽

Anna Aspán ◽

Stefan Alenius ◽

...

Keyword(s):

Escherichia Coli ◽

Control Measures ◽

Processing Plant ◽

Escherichia Coli O157 ◽

Meat Processing ◽

Cattle Farm ◽

Human Infections ◽

On Farm

In 2007, human infections with a hypervirulent strain of verocytotoxin-producing Escherichia coli O157:H7 increased in Sweden and especially in the Halland County. A connection between the cases and a local beef cattle farm with an on-farm abattoir and meat processing plant was established. In this observational study the control measures implemented on the infected farm and the dynamics of infection in the herd are described. In May 2008, when measures were initiated and animals put to pasture, the prevalence of positive individuals was 40 per cent and 18 carcasses out of 24 slaughtered animals were contaminated. During summer the monthly prevalence of positive carcasses varied between 8 and 41 per cent and at turning-in 22 out of 258 individually sampled animals were shedding the pathogen. After January 2009 no positive carcasses were found at slaughter and follow-up samplings of environment and individuals remained negative until the study period ended in May 2010. The results indicate that on-farm measures have potential to reduce the prevalence of the pathogen in a long-term perspective. However, as self-clearance cannot be excluded the effectiveness of the suggested measures needs to be confirmed.

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Identification of nontuberculous mycobacteria isolated from hospital water by sequence analysis of the hsp65 and 16S rRNA genes

Journal of Water and Health ◽

10.2166/wh.2017.046 ◽

2017 ◽

Vol 15 (5) ◽

pp. 766-774 ◽

Cited By ~ 4

Author(s):

Mehdi Roshdi Maleki ◽

Hossein Samadi Kafil ◽

Naser Harzandi ◽

Seyyed Reza Moaddab

Keyword(s):

Sequence Analysis ◽

16S Rrna ◽

Distribution Systems ◽

Water Distribution ◽

Nontuberculous Mycobacteria ◽

Cetylpyridinium Chloride ◽

Water Distribution Systems ◽

Single Species ◽

16S Rrna Genes ◽

Rrna Genes

Nontuberculous mycobacteria (NTM) have emerged as an important cause of opportunistic nosocomial infections. NTM has frequently been isolated from hospital water distribution systems. The aim of this study was to survey the risk of NTM infections and determine the prevalence of NTM species in the hospital water distribution systems in Tabriz, Iran. One hundred and twenty samples of water from different sources of Tabriz hospitals were collected. The samples were filtered through 0.45-µm pore size membranes and decontaminated with 0.01% cetylpyridinium chloride. The sediment was inoculated onto Lowenstein–Jensen medium and incubated for 8 weeks. For identification to the species level, partial sequence analysis of the hsp65 and 16S rRNA genes were used. NTM were detected in 76 (63.3%) of 120 samples. Potentially pathogenic mycobacteria and saprophytic mycobacteria were isolated. Mycobacterium gordonae was the only single species that was present in all types of water. The prevalence of NTM in Tabriz hospitals' water compared with many investigations on hospital waters was high. This indicates that the immunocompromised patients and transplant recipients are at risk of contamination which necessitates considering decontamination of water sources to prevent such potential hazards.

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STRATEGIE INNOVATIVE PER IL CONTROLLO DI ZANZARE, VETTORI DI ORGANISMI PATOGENI

Istituto Lombardo - Accademia di Scienze e Lettere - Rendiconti di Scienze ◽

10.4081/scie.2017.602 ◽

2020 ◽

Author(s):

Giuliano Gasperi

Keyword(s):

Reproductive Behaviour ◽

Pest Species ◽

Gene Drive ◽

West Nile Fever ◽

Environmentally Safe ◽

Safe Control ◽

Human Infections ◽

Species Being ◽

Harmful Species

Mosquitoes are the most dangerous insect species being the vectors of the pathogens causing the most widespread diseases as Malaria, Dengue fever, Chikungunya, West Nile fever, Yellow fever, Zika. Several species of the Anopheles, Aedes and Culex are responsable for millions of human infections causing hundreds of thousands of deaths per year. This causes dramatic socio-economic and health consequences, especially in developing countries. Harmful insects are controlled using chemical insecticides which cause insecticide resistance and environmental pollution, due to long term use. In the second half of the 20th century, new insect environmentally safe control stategies were been developed, based on the insect’s reproductive behaviour. Notably, the Sterile Insect Technique (SIT) has been successfully applied against some dipteran pest species in several regions of the World. It drived several research efforts to increase our knowledge of the biology of the harmful species. SIT improvements have been also achieved with several molecular biology approaches and transgene technologies such as the innovative RIDL, cytoplasmic incompatibility (CI) and gene drive.

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A survey of feline trichomonosis suggests a low incidence of Tritrichomonas blagburni among cats in the Czech Republic

Veterinární Medicína ◽

10.17221/106/2016-vetmed ◽

2017 ◽

Vol 62 (No. 5) ◽

pp. 269-273 ◽

Cited By ~ 2

Author(s):

V. Ceplecha ◽

V. Svobodova ◽

C. Lendon ◽

R. Husnik ◽

K. Horackova ◽

...

Keyword(s):

Czech Republic ◽

Single Case ◽

Risk Groups ◽

Species Differentiation ◽

Culture Methods ◽

The Czech Republic ◽

Pcr Screening ◽

Low Incidence ◽

Medium Method

Tritrichomonas blagburni (previously called T. foetus) has been implicated as an aetiological agent of long-term large-bowel diarrhoea in cats in many countries worldwide. The aim of this study was to determine the presence of, and risk factors for T. blagburni among a cohort of cats living in different conditions in the Czech Republic. Samples were collected from 170 cats living in different environments. The InPouch™ TF-Feline medium method was used for diagnosis of feline trichomonosis. A single case (0.6%) with motile trichomonads identified as Pentatrichomonas hominis was found in a cat from a multi-cat household. Our study suggests that trichomonads and in particular, T. blagburni, infection may be much less common in the Czech Republic than in neighbouring countries, despite the inclusion of cats that were likely to be from higher-risk groups. A review of studies of the association of trichomonads and feline diarrhoea carried out in different countries revealed variation in the frequency of trichomonads detected. Different combinations of PCR or culture methods for screening or confirmation have been utilised, with or without species differentiation; however, this could not solely account for the variation in the occurrence between countries. From those studies where differentiation was performed, we calculated from the combined studies that T. blagburni occurred in six cats without diarrhoea (1.1%) and 47 cases with diarrhoea (5%). This finding supports an association with diarrhoea as well as the occurrence of asymptomatic cases. We note that in many studies, including our own, the occurrence of T. blagburni may well be underestimated and suggest that future studies use a combination of PCR screening of both faeces and faecal cultures, with differentiation of trichomonad species.

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