1
|
Ditommaso S, Giacomuzzi M, Memoli G, Garlasco J, Curtoni A, Iannaccone M, Zotti CM. A New Culture Method for the Detection of Non-Tuberculous Mycobacteria in Water Samples from Heater-Cooler Units and Extracorporeal Membrane Oxygenation Machines. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:10645. [PMID: 36078363 PMCID: PMC9518321 DOI: 10.3390/ijerph191710645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/20/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
The isolation of non-tuberculous mycobacteria (NTM) from cultures is particularly laborious due to the potential overgrowth of coexisting non-acid fast bacilli. To reduce the overgrowth of these non-mycobacterial organisms, a decontamination step with NaOH or cetylpyridinium chloride is highly recommended before plating the samples on the culture medium. However, due to their toxicity, decontamination solutions tend to decrease NTM recovery from clinical and environmental samples. Here, we tested an alternative method for NTM recovery based on the use of NTM Elite agar, a selective medium that does not require a decontamination step. Using NTM Elite agar, we were able to detect non-tuberculous mycobacteria in 27.7% (30/108) of water samples analyzed. The average time to NTM detection was 18 days, but some strains required longer to grow, perhaps due to the stressful environmental conditions (periodical disinfection of devices). NTM Elite agar's effectiveness in inhibiting background flora was proven by the isolation of NTM from samples with and without background flora, showing no statistically significant differences in detection rates for different total viable counts of background flora (p = 0.4989). In conclusion, our findings indicate that effective NTM recovery from HCU- and ECMO-derived water samples can be achieved via filtration and direct culture of the filters on NTM Elite agar. This simple procedure can speed up laboratory work and provide an improved method, successfully resulting in low contamination and high detection rate, in addition to being less time-consuming. Its sensitivity and lack of a decontamination step make this protocol particularly useful for monitoring the effectiveness of device disinfection in hospital settings, even in the presence of low NTM loads. Reading timeframes should probably be extended to 7 weeks (i.e., well beyond the standard 4 weeks advised by the manufacturer), in order to isolate even the slow-growing mycobacteria. However, an extended incubation period is not necessary for exclusion of M. chimaera contamination of the devices, as M. chimaera isolation times do not generally exceed 3 weeks.
Collapse
Affiliation(s)
- Savina Ditommaso
- Department of Public Health and Pediatrics, University of Turin, 10126 Torino, Italy
| | - Monica Giacomuzzi
- Department of Public Health and Pediatrics, University of Turin, 10126 Torino, Italy
| | - Gabriele Memoli
- Department of Public Health and Pediatrics, University of Turin, 10126 Torino, Italy
| | - Jacopo Garlasco
- Department of Public Health and Pediatrics, University of Turin, 10126 Torino, Italy
| | - Antonio Curtoni
- Microbiology and Virology Unit, University Hospital Città della Salute e della Scienza di Torino, 10126 Torino, Italy
| | - Marco Iannaccone
- Microbiology and Virology Unit, University Hospital Città della Salute e della Scienza di Torino, 10126 Torino, Italy
| | - Carla M. Zotti
- Department of Public Health and Pediatrics, University of Turin, 10126 Torino, Italy
| |
Collapse
|
2
|
Rojas-Ponce G, Sauvageau D, Zemp R, Barkema HW, Evoy S. Use of uncoated magnetic beads to capture Mycobacterium smegmatis and Mycobacterium avium paratuberculosis prior detection by mycobacteriophage D29 and real-time-PCR. METHODS IN MICROBIOLOGY 2022; 197:106490. [PMID: 35595085 DOI: 10.1016/j.mimet.2022.106490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/11/2022] [Accepted: 05/11/2022] [Indexed: 11/25/2022]
Abstract
Uncoated tosyl-activated magnetic beads were evaluated to capture Mycobacterium smegmatis and Mycobacterium avium subspecies paratuberculosis (MAP) from spiked feces, milk, and urine. Centrifugation and uncoated magnetic beads recovered more than 99% and 93%, respectively, of 1.68 × 107 CFU/mL, 1.68 × 106 CFU/mL and 1.68 × 105 CFU/mL M. smegmatis cells resuspended in phosphate buffer saline. The use of magnetic beads was more efficient to concentrate cells from 1.68 × 104 CFU/mL of M. smegmatis than centrifugation. Likewise, the F57-qPCR detection of MAP cells was different whether they were recovered by beads or centrifugation; cycle threshold (Ct) was lower (p < 0.05) for the detection of MAP cells recovered by beads than centrifugation, indicative of greater recovery. Magnetic separation of MAP cells from milk, urine, and feces specimens was demonstrated by detection of F57 and IS900 sequences. Beads captured no less than 109 CFU/mL from feces and no less than 104 CFU/mL from milk and urine suspensions. In another detection strategy, M. smegmatis coupled to magnetic beads were infected by mycobacteriophage D29. Plaque forming units were observed after 24 h of incubation from urine samples containing 2 × 105 and 2 × 103 CFU/mL M. smegmatis. The results of this study provide a promising tool for diagnosis of tuberculosis and Johne's disease.
Collapse
Affiliation(s)
- Gabriel Rojas-Ponce
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB, Canada.
| | - Dominic Sauvageau
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada
| | - Roger Zemp
- Department of Electrical and Computer Engineering, Biomedical Engineering, University of Alberta, Edmonton, AB, Canada
| | - Herman W Barkema
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Stephane Evoy
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
3
|
Mtetwa HN, Amoah ID, Kumari S, Bux F, Reddy P. The source and fate of Mycobacterium tuberculosis complex in wastewater and possible routes of transmission. BMC Public Health 2022; 22:145. [PMID: 35057793 PMCID: PMC8781043 DOI: 10.1186/s12889-022-12527-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 01/06/2022] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND The Mycobacterium tuberculosis complex (MTBC) consists of causative agents of both human and animal tuberculosis and is responsible for over 10 million annual infections globally. Infections occur mainly through airborne transmission, however, there are possible indirect transmissions through a faecal-oral route which is poorly reported. This faecal-oral transmission could be through the occurrence of the microbe in environments such as wastewater. This manuscript, therefore, reviews the source and fate of MTBC in the wastewater environment, including the current methods in use and the possible risks of infections. RESULTS The reviewed literature indicates that about 20% of patients with pulmonary TB may have extra-pulmonary manifestations such as GITB, resulting in shedding in feaces and urine. This could potentially be the reason for the detection of MTBC in wastewater. MTBC concentrations of up to 5.5 × 105 (±3.9 × 105) copies/L of untreated wastewater have been reported. Studies have indicated that wastewater may provide these bacteria with the required nutrients for their growth and could potentially result in environmental transmission. However, 98.6 (± 2.7) %, removal during wastewater treatment, through physical-chemical decantation (primary treatment) and biofiltration (secondary treatment) has been reported. Despite these reports, several studies observed the presence of MTBC in treated wastewater via both culture-dependent and molecular techniques. CONCLUSION The detection of viable MTBC cells in either treated or untreated wastewater, highlights the potential risks of infection for wastewater workers and communities close to these wastewater treatment plants. The generation of aerosols during wastewater treatment could be the main route of transmission. Additionally, direct exposure to the wastewater containing MTBC could potentially contribute to indirect transmissions which may lead to pulmonary or extra-pulmonary infections. This calls for the implementation of risk reduction measures aimed at protecting the exposed populations.
Collapse
Affiliation(s)
- Hlengiwe N Mtetwa
- Department of Community Health Studies, Faculty of Health Sciences, Durban University of Technology, PO Box 1334, Durban, 4000, South Africa
- Institute for Water and Wastewater Technology (IWWT), Durban University of Technology, PO Box 1334, Durban, 4000, South Africa
| | - Isaac D Amoah
- Institute for Water and Wastewater Technology (IWWT), Durban University of Technology, PO Box 1334, Durban, 4000, South Africa
| | - Sheena Kumari
- Institute for Water and Wastewater Technology (IWWT), Durban University of Technology, PO Box 1334, Durban, 4000, South Africa
| | - Faizal Bux
- Institute for Water and Wastewater Technology (IWWT), Durban University of Technology, PO Box 1334, Durban, 4000, South Africa
| | - Poovendhree Reddy
- Department of Community Health Studies, Faculty of Health Sciences, Durban University of Technology, PO Box 1334, Durban, 4000, South Africa.
| |
Collapse
|
4
|
Ditommaso S, Giacomuzzi M, Memoli G, Garlasco J, Curtoni A, Iannaccone M, Zotti CM. Chemical susceptibility testing of non-tuberculous mycobacterium strains and other aquatic bacteria: Results of a study for the development of a more sensitive and simple method for the detection of NTM in environmental samples. J Microbiol Methods 2022; 193:106405. [PMID: 34990646 DOI: 10.1016/j.mimet.2021.106405] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/30/2021] [Accepted: 12/30/2021] [Indexed: 12/27/2022]
Abstract
The methods employed to detect non-tuberculous mycobacteria on environmental samples are essentially those classically used in clinical microbiology, which envisage a decontamination step to reduce the overgrowth of non-mycobacterial organisms before plating them on the culture medium. The aim of this study was to propose alternative culture techniques to improve non-tuberculous mycobacteria detection in environmental samples. We used artificially contaminated samples to compare the membrane filter washing procedure against direct plating of membrane filters on culture media in relation to M.chimaera and M.chelonae recovery efficiency. Moreover, we compared the efficacy of NTM Elite agar in inhibiting the growth of aquatic bacteria with that of cetylpyridinium chloride and N-acetyl-L-cysteine sodium hydroxide decontamination treatments. The washing procedure yielded a low release of both mycobacterium strains (6.6% for Mycobacterium chimaera and 7.5% for Mycobacterium chelonae) from the membrane filters; on the contrary, direct plating of membrane filters led to a 100% cell recovery. Water sample pretreatment with N-acetyl-L-cysteine sodium hydroxide (1%), despite achieving complete suppression of non-acid fast bacilli, caused a reduction in mycobacteria growth. Decontamination with cetylpyridinium chloride (0.005%) was found to be ineffective against Methylobacterium spp. and Burkholderia multivorans. NTM Elite agar was ineffective against B. multivorans, but it inhibited the growth of all other aquatic bacteria. Our results indicate that NTM Elite agar provides a valid alternative method of recovering non-tuberculous mycobacteria from environmental samples. It does not involve a decontamination step and provides greater recovery efficiency by skipping the washing step and directly plating the filters on the media.
Collapse
Affiliation(s)
- Savina Ditommaso
- Department of Public Health and Pediatrics, University of Turin, Italy.
| | - Monica Giacomuzzi
- Department of Public Health and Pediatrics, University of Turin, Italy
| | - Gabriele Memoli
- Department of Public Health and Pediatrics, University of Turin, Italy
| | - Jacopo Garlasco
- Department of Public Health and Pediatrics, University of Turin, Italy
| | - Antonio Curtoni
- Microbiology and Virology Unit, University Hospital Citta della Salute e della Scienza di Torino, Turin, Italy
| | - Marco Iannaccone
- Microbiology and Virology Unit, University Hospital Citta della Salute e della Scienza di Torino, Turin, Italy
| | - Carla Maria Zotti
- Department of Public Health and Pediatrics, University of Turin, Italy
| |
Collapse
|
5
|
Ulmann V, Modrá H, Babak V, Weston RT, Pavlik I. Recovery of Mycobacteria from Heavily Contaminated Environmental Matrices. Microorganisms 2021; 9:microorganisms9102178. [PMID: 34683499 PMCID: PMC8538195 DOI: 10.3390/microorganisms9102178] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 11/22/2022] Open
Abstract
For epidemiology studies, a decontamination method using a solution containing 4.0% NaOH and 0.5% tetradecyltrimethylammonium bromide (TDAB) represents a relatively simple and universal procedure for processing heavily microbially contaminated matrices together with increase of mycobacteria yield and elimination of gross contamination. A contamination rate only averaging 7.3% (2.4% in Cluster S; 6.9% in Cluster R and 12.6% in Cluster E) was found in 787 examined environmental samples. Mycobacteria were cultured from 28.5% of 274 soil and water sediments samples (Cluster S), 60.2% of 251 samples of raw and processed peat and other horticultural substrates (Cluster R), and 29.4% of 262 faecal samples along with other samples of animal origin (Cluster E). A total of 38 species of slow and rapidly growing mycobacteria were isolated. M. avium ssp. hominissuis, M. fortuitum and M. malmoense were the species most often isolated. The parameters for the quantitative detection of mycobacteria by PCR can be significantly refined by treating the sample suspension before DNA isolation with PMA (propidium monoazide) solution. This effectively eliminates DNA residue from both dead mycobacterial cells and potentially interfering DNA segments present from other microbial flora. In terms of human exposure risk assessment, the potential exposure to live non-tuberculous mycobacteria can be more accurately determined.
Collapse
Affiliation(s)
- Vit Ulmann
- Public Health Institute in Ostrava, Partyzanske Nam. 7, 702 00 Ostrava, Czech Republic;
| | - Helena Modrá
- Faculty of Regional Development and International Studies, Mendel University in Brno, Tr. Generala Piky 7, 613 00 Brno, Czech Republic;
| | - Vladimir Babak
- Veterinary Research Institute, v.v.i., Hudcova 70, 621 00 Brno, Czech Republic;
| | - Ross Tim Weston
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Melbourne, VIC 3086, Australia;
| | - Ivo Pavlik
- Faculty of Regional Development and International Studies, Mendel University in Brno, Tr. Generala Piky 7, 613 00 Brno, Czech Republic;
- Correspondence: ; Tel.: +420-773-491-836
| |
Collapse
|
6
|
Algammal AM, Hashem HR, Al-Otaibi AS, Alfifi KJ, El-Dawody EM, Mahrous E, Hetta HF, El-Kholy AW, Ramadan H, El-Tarabili RM. Emerging MDR-Mycobacterium avium subsp. avium in house-reared domestic birds as the first report in Egypt. BMC Microbiol 2021; 21:237. [PMID: 34445951 PMCID: PMC8393820 DOI: 10.1186/s12866-021-02287-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 07/26/2021] [Indexed: 12/01/2022] Open
Abstract
Background Avian tuberculosis is a chronic and zoonotic disease that affects a wide variety of birds, mammals, and humans. This study aimed to estimate the frequency of Mycobacterium avium subsp. avium in some domestic birds based on molecular diagnosis, antibiogram profile, and PCR-based detection of inhA, rpoB, rpsL, and otrB antibiotic resistance-related genes. Methods A total of 120 fecal samples were collected from small flocks of house-reared domestic birds at Ismailia Governorate, Egypt. The collected samples were processed and subjected to the bacteriological examination. The antimicrobial susceptibility testing of the recovered isolates was performed using the broth microdilution method for the detection of minimum inhibitory concentrations (MICs). The genetic detection of the IS901confirmatory gene, inhA, rpoB, rpsL, and otrB genes was carried out using PCR. Results The frequency of M. avium subsp. avium was 4.1% (5/120); 10% (4/40) in ducks, and 2.5% (1/10) in geese. The identification of the recovered isolates was confirmed using PCR, where all the tested isolates were positive for IS901confirmatory gene. The results of the broth microdilution method revealed that most of the recovered isolates exhibited multidrug resistance (MDR) to isoniazid, rifampicin, streptomycin, oxytetracycline, and doxycycline, and harbored the inhA, rpoB, rpsL, and otrB genes. Conclusion In brief, to the best of our knowledge this is the first report that emphasized the emergence of avian tuberculosis in house-reared domestic birds in Egypt. The emergence of MDR- M. avium subsp. avium is considered a public health threat. Emerging MDR-M. avium subsp. avium in domestic birds are commonly harbored the IS901, inhA, rpoB, rpsL, and otrB genes. Azithromycin and clofazimine revealed a promising in-vitro antibacterial activity against M. avium subsp. avium.
Collapse
Affiliation(s)
- Abdelazeem M Algammal
- Department of Bacteriology, Immunology and Mycology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, 41522, Egypt.
| | - Hany R Hashem
- Department of Microbiology and Immunology, Faculty of Pharmacy, Fayoum University, Fayoum, 63514, Egypt
| | - Amenah S Al-Otaibi
- Biology Department, College of Sciences, Tabuk University, Tabuk, 71491, Saudi Arabia
| | - Khyreyah J Alfifi
- Biology Department, College of Sciences, Tabuk University, Tabuk, 71491, Saudi Arabia
| | | | - Eman Mahrous
- Animal Health Research Institute, Dokki, Giza, 12618, Egypt
| | - Helal F Hetta
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assuit University, Assuit, 71515, Egypt
| | - Ali W El-Kholy
- Department of Bacteriology, Immunology and Mycology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, 41522, Egypt
| | - Hazem Ramadan
- Hygiene and Zoonoses Department, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt
| | - Reham M El-Tarabili
- Department of Bacteriology, Immunology and Mycology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, 41522, Egypt
| |
Collapse
|
7
|
ISOLATION AND ANTIMICROBIAL SUSCEPTIBILITIES OF NONTUBERCULOUS MYCOBACTERIA FROM WILDLIFE IN JAPAN. J Wildl Dis 2021; 56:851-862. [PMID: 32402237 DOI: 10.7589/2019-10-261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 02/25/2020] [Indexed: 11/20/2022]
Abstract
Nontuberculous mycobacteria (NTM) are opportunistic pathogens of humans and animals and are transmitted among the environment, wildlife, livestock, and humans. The aim of this study was to investigate the rate of isolation and antimicrobial susceptibility of NTM in wildlife. In total, 178 samples of feces (n=131) and tissues (n=47) were collected from 11 wildlife species in Gifu Prefecture and Mie Prefecture, Japan, between June 2016 and October 2018. We isolated NTM from 15.3% (20/ 131) of fecal samples using Ogawa medium, and isolates were identified by sequencing the rpoB and hsp65 genes. The rpoB sequences were compared with those from other strains of human and environmental origin. The NTM isolates were obtained from sika deer (Cervus nippon), wild boar (Sus scrofa), Japanese monkey (Macaca fuscata), raccoon dog (Nyctereutes procyonoides), masked palm civet (Paguma larvata), and Japanese weasel (Mustela itatsi) and were classified as rapidly growing mycobacteria (RGM) and slowly growing mycobacteria (SGM). The 12 RGM identified were Mycolicibacterium peregrinum (n=5), Mycolicibacterium fortuitum (n=3), Mycolicibacterium septicum (n=3), and Mycolicibacterium thermoresistibile (n=1), and the eight SGM were Mycobacterium paraense (n=4), Mycolicibacter arupensis (n=2), Mycolicibacter virginiensis (n=1), and Mycobacterium nebraskense (n=1). The NTM from wildlife showed ≥99% similarity with strains from different sources including humans. The RGM were susceptible to the antimicrobial agents tested except for M. fortuitum, which was resistant to azithromycin and clarithromycin. The SGM showed multiple drug resistance qualities but were susceptible to amikacin, clarithromycin, and rifabutin. These results indicate that wildlife may be reservoir hosts of NTM in Japan. The presence of antimicrobial-resistant NTM in wildlife suggests that the trends of NTM antimicrobial susceptibility in wildlife should be monitored.
Collapse
|
8
|
Zoccola R, Di Blasio A, Bossotto T, Pontei A, Angelillo M, Dondo A, Goria M, Zoppi S. Validation of a Novel Diagnostic Approach Combining the VersaTREK™ System for Recovery and Real-Time PCR for the Identification of Mycobacterium chimaera in Water Samples. Microorganisms 2021; 9:microorganisms9051031. [PMID: 34064701 PMCID: PMC8150998 DOI: 10.3390/microorganisms9051031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/03/2021] [Accepted: 05/09/2021] [Indexed: 11/16/2022] Open
Abstract
Mycobacterium chimaera is an emerging pathogen associated with endocarditis and vasculitis following cardiac surgery. Although it can take up to 6-8 weeks to culture on selective solid media, culture-based detection remains the gold standard for diagnosis, so more rapid methods are urgently needed. For the present study, we processed environmental M. chimaera infected simulates at volumes defined in international guidelines. Each preparation underwent real-time PCR; inoculates were placed in a VersaTREK™ automated microbial detection system and onto selective Middlebrook 7H11 agar plates. The validation tests showed that real-time PCR detected DNA up to a concentration of 10 ng/µL. A comparison of the isolation tests showed that the PCR method detected DNA in a dilution of ×102 CFU/mL in the bacterial suspensions, whereas the limit of detection in the VersaTREK™ was <10 CFU/mL. Within less than 3 days, the VersaTREK™ detected an initial bacterial load of 100 CFU. The detection limit did not seem to be influenced by NaOH decontamination or the initial water sample volume; analytical sensitivity was 1.5 × 102 CFU/mL; positivity was determined in under 15 days. VersaTREK™ can expedite mycobacterial growth in a culture. When combined with PCR, it can increase the overall recovery of mycobacteria in environmental samples, making it potentially applicable for microbial control in the hospital setting and also in environments with low levels of contamination by viable mycobacteria.
Collapse
Affiliation(s)
- Roberto Zoccola
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, 10154 Torino, Italy; (R.Z.); (T.B.); (A.P.); (M.A.); (A.D.); (M.G.); (S.Z.)
| | - Alessia Di Blasio
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, 10154 Torino, Italy; (R.Z.); (T.B.); (A.P.); (M.A.); (A.D.); (M.G.); (S.Z.)
- Azienda Sanitaria Locale TO3 S.C. Sanità Animale, Pinerolo, 10064 Torino, Italy
- Correspondence: ; Tel.: +39-0121-235489
| | - Tiziana Bossotto
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, 10154 Torino, Italy; (R.Z.); (T.B.); (A.P.); (M.A.); (A.D.); (M.G.); (S.Z.)
| | - Angela Pontei
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, 10154 Torino, Italy; (R.Z.); (T.B.); (A.P.); (M.A.); (A.D.); (M.G.); (S.Z.)
| | - Maria Angelillo
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, 10154 Torino, Italy; (R.Z.); (T.B.); (A.P.); (M.A.); (A.D.); (M.G.); (S.Z.)
| | - Alessandro Dondo
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, 10154 Torino, Italy; (R.Z.); (T.B.); (A.P.); (M.A.); (A.D.); (M.G.); (S.Z.)
| | - Maria Goria
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, 10154 Torino, Italy; (R.Z.); (T.B.); (A.P.); (M.A.); (A.D.); (M.G.); (S.Z.)
| | - Simona Zoppi
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, 10154 Torino, Italy; (R.Z.); (T.B.); (A.P.); (M.A.); (A.D.); (M.G.); (S.Z.)
| |
Collapse
|
9
|
Sattar A, Zakaria Z, Abu J, Aziz SA, Rojas-Ponce G. Isolation of Mycobacterium avium and other nontuberculous mycobacteria in chickens and captive birds in peninsular Malaysia. BMC Vet Res 2021; 17:13. [PMID: 33413380 PMCID: PMC7791791 DOI: 10.1186/s12917-020-02695-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 11/24/2020] [Indexed: 11/30/2022] Open
Abstract
Background Mycobacterium avium complex (MAC) causes a chronic infectious in the birds known as avian mycobacteriosis. Almost all species of the birds are susceptible to MAC which consists of two closely related species of mycobacteria, that is, M. avium and M. intracellulare. This study aimed to determine the occurrence of Mycobacterium avium subsp. avium (MAA) in chickens and captive birds in selected states of Peninsular Malaysia. Results A 300 fecal samples were collected from village chickens (n = 100), layer chickens (n = 100) and captive birds (n = 100). Fecal samples were split into two aliquots for microbiological and molecular detection of MAA. Microbiology detection consisted of microscopy (Ziehl-Neelsen staining) and culture of samples decontaminated with 1% Cetylperidinium chloride and vancomycin, nalidixic acid and amphotericin B (VNA) antibiotic cocktail [vancomycin (VAN) 100 μg/ml, nalidixic acid (NAL) 100 μg/ml and amphotericin B (AMB) 50 μg/ml] onto Löwenstein-Jensen (L-J). Molecular detection (PCR-IS901) was performed to detect MAA DNA from the feces and PCR-16S rRNA and IS901 for identification of genus Mycobacterium and Mycobacterium avium sub species avium isolated onto L-J. All samples (296) were AFB negative smear. M. avium was isolated in 0.3% (1/296) samples by culture and detected in 2.5% (6/242) samples by PCR (IS901). Other mycobacteria were found in 1.7% (5/296) chickens. Of five isolates, two were identified as Mycobacterium terrae and M. engbaekii and remaining isolates were not sequenced. Birds positive for M. avium included White Pelican (n = 1) Black Hornbill (n = 1), Macaw (n = 2), Cockatoo (n = 2) and village chicken (n = 1). Conclusion It is concluded that chickens and birds were infected with M. avium in selected areas of Peninsular Malaysia. Although, PCR is rapid, reliable and cost effective method for detection of M. avium in a subclinical stage, the culture of the avian feces should still be used as a reference test for the diagnosis of avian tuberculosis.
Collapse
Affiliation(s)
- Abdul Sattar
- Faculty of Veterinary and Animal Sciences, Lasbela University of Agriculture, Water and Marine Sciences, Uthal, Balochistan, 90150, Pakistan.,Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia UPM, 43400, Serdang, Selangor, Malaysia
| | - Zunita Zakaria
- Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia UPM, 43400, Serdang, Selangor, Malaysia. .,Institute of Bioscience, Universiti Putra Malaysia, 43400-UPM, Serdang, Selangor, Malaysia.
| | - Jalila Abu
- Department of Clinical Studies, Faculty of Veterinary Medicine, Universiti Putra Malaysia UPM, 43400, Serdang, Selangor, Malaysia
| | - Saleha A Aziz
- Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia UPM, 43400, Serdang, Selangor, Malaysia
| | - Gabriel Rojas-Ponce
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, T6G 2V4, Canada
| |
Collapse
|
10
|
Babazadeh D, Asasi K. EFFECTS OF IN OVO SYNBIOTIC INJECTION ON GROWTH PERFORMANCE, INTESTINAL BACTERIAL LOAD AND ANTIBODY TITRES IN BROILER CHICKENS VACCINATED AGAINST INFECTIOUS BURSAL DISEASE. BULGARIAN JOURNAL OF VETERINARY MEDICINE 2021. [DOI: 10.15547/bjvm.2298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The present study investigated the efficacy of a synbiotic (Lactobacillus delbrueckii subsp. bulgar-icus, Streptococcus salivarius subsp. thermophilus, and mannan oligosaccharide) along with an infectious bursal disease (IBD) vaccine in Cobb 500 broilers. A total of 1200 embryonated chicken eggs were randomly allocated in 10 groups with eight replicates. The first group did not receive any treatment. The second group was vaccinated post-hatch (PV), the third group was vaccinated in ovo (IV), the fourth group received dietary synbiotic and in ovo vaccination (DS+IV), the fifth group was treated in ovo with synbiotic (IS), the sixth group received in ovo and dietary synbiotic (IS+DS), the seventh group received in ovo synbiotic plus post-hatch vaccination (IS+PV) and the eighth group in ovo and dietary synbiotic and post-hatch vaccination (IS+DS+PV). In the ninth group, the synbiotic and the vaccine were administered in ovo (IS+IV) while the tenth group re-ceived in ovo and dietary synbiotic, plus in ovo vaccine (IS+DS+IV). The in ovo treatment with the synbiotic in combination with DS, IV or PV had a positive effect on weekly weight gain. The sixth group provided a better feed conversion ratio at the end of fourth week. The synbiotic appli-cation, individually in sixth group or along with PV or IV treatment in eighth and tenth groups, elevated feed intake in fifth and sixth weeks respectively.The antibody titre of IBD was higher for groups which received IV along with IS. It is concluded that the application of synbiotic along to IBD vaccine improved growth performance and had positive effects on IBD antibody titres.
Collapse
Affiliation(s)
- D. Babazadeh
- Poultry Diseases Research Center, Clinical Sciences Section, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
| | - K. Asasi
- Poultry Diseases Research Center, Clinical Sciences Section, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
| |
Collapse
|
11
|
Lekko YM, Ooi PT, Omar S, Mazlan M, Ramanoon SZ, Jasni S, Jesse FFA, Che-Amat A. Mycobacterium tuberculosis complex in wildlife: Review of current applications of antemortem and postmortem diagnosis. Vet World 2020; 13:1822-1836. [PMID: 33132593 PMCID: PMC7566238 DOI: 10.14202/vetworld.2020.1822-1836] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 07/16/2020] [Indexed: 12/31/2022] Open
Abstract
Tuberculosis (TB) is a chronic inflammatory and zoonotic disease caused by Mycobacterium tuberculosis complex (MTBC) members, which affects various domestic animals, wildlife, and humans. Some wild animals serve as reservoir hosts in the transmission and epidemiology of the disease. Therefore, the monitoring and surveillance of both wild and domestic hosts are critical for prevention and control strategies. For TB diagnosis, the single intradermal tuberculin test or the single comparative intradermal tuberculin test, and the gamma-interferon test, which is regarded as an ancillary test, are used. Postmortem examination can identify granulomatous lesions compatible with a diagnosis of TB. In contrast, smears of the lesions can be stained for acid-fast bacilli, and samples of the affected organs can be subjected to histopathological analyses. Culture is the gold standard test for isolating mycobacterial bacilli because it has high sensitivity and specificity compared with other methods. Serology for antibody detection allows the testing of many samples simply, rapidly, and inexpensively, and the protocol can be standardized in different laboratories. Molecular biological analyses are also applicable to trace the epidemiology of the disease. In conclusion, reviewing the various techniques used in MTBC diagnosis can help establish guidelines for researchers when choosing a particular diagnostic method depending on the situation at hand, be it disease outbreaks in wildlife or for epidemiological studies. This is because a good understanding of various diagnostic techniques will aid in monitoring and managing emerging pandemic threats of infectious diseases from wildlife and also preventing the potential spread of zoonotic TB to livestock and humans. This review aimed to provide up-to-date information on different techniques used for diagnosing TB at the interfaces between wildlife, livestock, and humans.
Collapse
Affiliation(s)
- Yusuf Madaki Lekko
- Department of Veterinary Clinical Studies, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.,Department of Veterinary Medicine, Faculty of Veterinary Medicine, University of Maiduguri, 1069 PMB, Maiduguri, Borno State, Nigeria
| | - Peck Toung Ooi
- Department of Veterinary Clinical Studies, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Sharina Omar
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Mazlina Mazlan
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Siti Zubaidah Ramanoon
- Department of Farm and Exotic Animal Medicine and Surgery, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Sabri Jasni
- Department of Paraclinical, Faculty of Veterinary Medicine, Universiti Malaysia Kelantan, Pengkalan Chepa, 16100 Kota Bharu, Kelantan, Malaysia
| | - Faez Firdaus Abdullah Jesse
- Department of Veterinary Clinical Studies, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Azlan Che-Amat
- Department of Veterinary Clinical Studies, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| |
Collapse
|
12
|
Pereira AC, Ramos B, Reis AC, Cunha MV. Non-Tuberculous Mycobacteria: Molecular and Physiological Bases of Virulence and Adaptation to Ecological Niches. Microorganisms 2020; 8:microorganisms8091380. [PMID: 32916931 PMCID: PMC7563442 DOI: 10.3390/microorganisms8091380] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 09/06/2020] [Accepted: 09/07/2020] [Indexed: 12/15/2022] Open
Abstract
Non-tuberculous mycobacteria (NTM) are paradigmatic colonizers of the total environment, circulating at the interfaces of the atmosphere, lithosphere, hydrosphere, biosphere, and anthroposphere. Their striking adaptive ecology on the interconnection of multiple spheres results from the combination of several biological features related to their exclusive hydrophobic and lipid-rich impermeable cell wall, transcriptional regulation signatures, biofilm phenotype, and symbiosis with protozoa. This unique blend of traits is reviewed in this work, with highlights to the prodigious plasticity and persistence hallmarks of NTM in a wide diversity of environments, from extreme natural milieus to microniches in the human body. Knowledge on the taxonomy, evolution, and functional diversity of NTM is updated, as well as the molecular and physiological bases for environmental adaptation, tolerance to xenobiotics, and infection biology in the human and non-human host. The complex interplay between individual, species-specific and ecological niche traits contributing to NTM resilience across ecosystems are also explored. This work hinges current understandings of NTM, approaching their biology and heterogeneity from several angles and reinforcing the complexity of these microorganisms often associated with a multiplicity of diseases, including pulmonary, soft-tissue, or milliary. In addition to emphasizing the cornerstones of knowledge involving these bacteria, we identify research gaps that need to be addressed, stressing out the need for decision-makers to recognize NTM infection as a public health issue that has to be tackled, especially when considering an increasingly susceptible elderly and immunocompromised population in developed countries, as well as in low- or middle-income countries, where NTM infections are still highly misdiagnosed and neglected.
Collapse
Affiliation(s)
- André C. Pereira
- Centre for Ecology, Evolution and Environmental Changes (cE3c), Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal; (A.C.P.); (B.R.); (A.C.R.)
- Biosystems & Integrative Sciences Institute (BioISI), Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Beatriz Ramos
- Centre for Ecology, Evolution and Environmental Changes (cE3c), Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal; (A.C.P.); (B.R.); (A.C.R.)
- Biosystems & Integrative Sciences Institute (BioISI), Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Ana C. Reis
- Centre for Ecology, Evolution and Environmental Changes (cE3c), Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal; (A.C.P.); (B.R.); (A.C.R.)
- Biosystems & Integrative Sciences Institute (BioISI), Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Mónica V. Cunha
- Centre for Ecology, Evolution and Environmental Changes (cE3c), Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal; (A.C.P.); (B.R.); (A.C.R.)
- Biosystems & Integrative Sciences Institute (BioISI), Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Correspondence: ; Tel.: +351-217-500-000 (ext. 22461)
| |
Collapse
|
13
|
Hassan AA, Khan IUH, Ganz S, Wehrend A, Failing K, Eisenberg T, Abdulmawjood A, Bülte M. Assessing efficacy of N-Acetyl-l-Cysteine-Sodium Hydroxide on bacterial viability and enhanced recovery of Mycobacterium avium subsp. paratuberculosis from bovine colostrum. J Microbiol Methods 2020; 175:105968. [PMID: 32479871 DOI: 10.1016/j.mimet.2020.105968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 05/28/2020] [Accepted: 05/28/2020] [Indexed: 10/24/2022]
Abstract
The standard procedure for the improved cultural recovery of viable Mycobacterium spp. from diverse samples mainly depends on reducing the viability of background microbiota using different chemical compounds. This study was designed to i) evaluate the efficacy and comparison between N-Acetyl-l-Cysteine-Sodium hydroxide (NALC-2% NaOH) and hexadecylpyridinium chloride (0.75% HPC) treatment and exposure time on reducing the viability of undesirable microorganisms with minimal impact on colostrum consistency; and ii) assess the impact of NALC-2% NaOH on improved and enhanced recovery of Mycobacterium avium subsp. paratuberculosis (MAP) in spiked postpartum colostrum samples and consistency of colostrum. A total of 40 samples, each treated with NALC-2% NaOH for 15 min or 0.75% HPC for 5 h, were investigated for total mesophilic aerobic bacteria (MAB) and enterobacteria (EB) (CFU mL-1). The results showed that treatment of colostrum samples with NALC-2% NaOH completely eliminated EB and significantly reduced MAB (3.6 log10 CFU mL-1). Conversely, samples treated with 0.75% HPC produced a complex mixture following interaction with the colostrum protein and showed non-significant and variable results. In addition, the spiked colostrum treated with NALC-2% NaOH for 15 min revealed recovery of viable MAP cells with a minimum limit of detection of 1.36 log10 CFU 10 mL-1 where no change in the consistency of colostrum was observed. In conclusion, 15-min NALC-2% NaOH treatment of colostrum may significantly reduce the viability of undesirable microorganisms and help to enhance the efficient recovery of MAP without impacting the consistency of high quality postpartum colostrum. This rapid procedure is suitable for efficient recovery and early detection of MAP as well as preventing its transmission to neonates and young calves in MAP infected herds.
Collapse
Affiliation(s)
- Abdulwahed Ahmed Hassan
- Institute of Veterinary Food Science, Justus-Liebig-University Gießen, Frankfurter Street 92, D-35392 Gießen, Germany; Department of Veterinary Public Health (DVPH), College of Veterinary Medicine, Mosul University, Mosul, Iraq.
| | - Izhar U H Khan
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, ON K1A 0C6, Canada
| | - Sebastian Ganz
- Klinik für Geburtshilfe, Gynäkologie und Andrologie der Groß- und Kleintiere mit Tierärztlicher Ambulanz, Justus-Liebig-University Gießen, Frankfurter Str. 106, D-35392 Gießen, Germany
| | - Axel Wehrend
- Klinik für Geburtshilfe, Gynäkologie und Andrologie der Groß- und Kleintiere mit Tierärztlicher Ambulanz, Justus-Liebig-University Gießen, Frankfurter Str. 106, D-35392 Gießen, Germany
| | - Klaus Failing
- Biomathematik und Datenverarbeitung, Justus-Liebig-University Gießen, Frankfurter Str. 95, D-35392 Gießen, Germany
| | - Tobias Eisenberg
- Landesbetrieb Hessisches Landeslabor, Schubertstr. 60, 35392 Gießen, Germany
| | - Amir Abdulmawjood
- Institute of Food Quality and Food Safety, Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany
| | - Michael Bülte
- Institute of Veterinary Food Science, Justus-Liebig-University Gießen, Frankfurter Street 92, D-35392 Gießen, Germany
| |
Collapse
|
14
|
Akter M, Islam MS, Islam MA, Sobur MA, Jahan MS, Rahman S, Nazmul Hussain Nazir KHM, Rahman MT. Migratory birds as the potential source for the transmission of Aspergillus and other fungus to Bangladesh. J Adv Vet Anim Res 2020; 7:338-344. [PMID: 32607367 PMCID: PMC7320803 DOI: 10.5455/javar.2020.g427] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/18/2020] [Accepted: 04/26/2020] [Indexed: 11/03/2022] Open
Abstract
Objectives Migratory birds play a major role in the transmission of pathogens globally, but still their role in the transmission of fungi in Bangladesh is not known. The present study was carried out for the isolation and molecular detection of fungi including Aspergillus from migratory birds traveling to Bangladesh. Materials and methods A total of 50 fecal samples were collected from BaojaniBaor, Magura, and areas close to Jahangirnagar University, Savar. The isolation of fungus was based on culture on Potato Dextrose Agar (PDA), followed by staining, morphology, and molecular detection using polymerase chain reaction (PCR). Results Among 50 samples, 40 showed positive for fungal growth on PDA, of which 30 yield only yeast-like colonies, five only molds, and five yielded both yeast and molds. The isolated molds produced various pigmented colonies, namely, black, whitish, grayish, olive green, and yellow. Among 10 molds, six were confirmed as fungi by PCR using genus-specific primers such as ITS1 and ITS4. Later, of these six fungi, five were confirmed as Aspergillus by PCR with primers such as ASAP1 and ASAP2 specific for Aspergillus genus. Therefore, the overall occurrence of Aspergillus was 10% (5/50). PCR specific for Aspergillus fumigatus and Aspergillus niger failed to produce specific PCR amplicon, suggesting that the isolated Aspergillus belongs to other groups. Conclusion This is the first report describing the isolation and molecular detection of Aspergillus from fecal samples of migratory birds in Bangladesh. The present findings confirm that migratory birds are potential source for Aspergillus and other fungus in Bangladesh.
Collapse
Affiliation(s)
- Mily Akter
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Md Saiful Islam
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Md Amirul Islam
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Md Abdus Sobur
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Md Salim Jahan
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Saifur Rahman
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - K H M Nazmul Hussain Nazir
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| | - Md Tanvir Rahman
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
| |
Collapse
|
15
|
Ditommaso S, Giacomuzzi M, Memoli G, Cavallo R, Curtoni A, Avolio M, Silvestre C, Zotti CM. Reduction of turnaround time for non-tuberculous mycobacteria detection in heater-cooler units by propidium monoazide-real-time polymerase chain reaction. J Hosp Infect 2019; 104:365-373. [PMID: 31628958 DOI: 10.1016/j.jhin.2019.10.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 10/08/2019] [Accepted: 10/10/2019] [Indexed: 11/17/2022]
Abstract
BACKGROUND Invasive non-tuberculous mycobacteria (NTM) infections are emerging worldwide in patients undergoing open-chest cardiac bypass surgery exposed to contaminated heater-cooler units (HCUs). Although this outbreak has been investigated by culturing bacteria isolated from HCU aerosol and water samples, these conventional methods have low-analytic sensitivity, high rates of sample contamination, and long turnaround time. AIM To develop a simple and effective method to detect NTM in HCUs by real-time polymerase chain reaction (PCR), with a short laboratory turnaround time and reliable culture results. METHODS A total of 281 water samples collected from various HCUs at seven Italian hospitals were simultaneously screened for NTM by a propidium monoazide (PMA)-PCR assay and by conventional culture testing. The results were analysed with culture testing as the reference method. FINDINGS (i) The agreement between culture testing and PMA-PCR was 85.0% with a cycle threshold (CT) cut-off value of <38 vs 80.0% with a CT of <43, with a moderate Cohen's κ-coefficient; (ii) the CT cut-off value of <42 was deemed more suitable for predicting positive specimens; (iii) given the low concentration of target DNA in water samples, the minimum volume to be tested was 1 L. CONCLUSION The use of PMA-PCR for fast detection of NTM from environmental samples is highly recommended in order to ascertain whether HCUs may represent a potential source of human exposure to NTM. This reliable and simple method reduces laboratory turnaround time compared to conventional methods (one to two days vs eight weeks, respectively), thereby improving control strategies and effective management of HCUs.
Collapse
Affiliation(s)
- S Ditommaso
- Department of Public Health and Pediatrics, University of Turin, Turin, Italy.
| | - M Giacomuzzi
- Department of Public Health and Pediatrics, University of Turin, Turin, Italy
| | - G Memoli
- Department of Public Health and Pediatrics, University of Turin, Turin, Italy
| | - R Cavallo
- Department of Public Health and Pediatrics, University of Turin, Turin, Italy; Microbiology and Virology Unit, University Hospital Città della Salute e della Scienza di Torino, Turin, Italy
| | - A Curtoni
- Microbiology and Virology Unit, University Hospital Città della Salute e della Scienza di Torino, Turin, Italy
| | - M Avolio
- Microbiology and Virology Unit, University Hospital Città della Salute e della Scienza di Torino, Turin, Italy
| | - C Silvestre
- AOU Città della salute e della Scienza, Turin, Italy
| | - C M Zotti
- Department of Public Health and Pediatrics, University of Turin, Turin, Italy
| |
Collapse
|