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Mycobacterium gordonae is a nontuberculous mycobacterium found in diverse environments and is considered an opportunistic pathogen in immunocompromised patients. We report the draft genome sequence of a Mycobacterium gordonae strain isolated from a free-living amoeba found in a nosocomial environment in Lima, Peru.

The list of clinically important nontuberculous mycobacteria (NTM) is growing as new species continue to be identified and older ones are found to be pathogenic. Molecular techniques such as real-time PCR and gene amplification and restriction length polymorphism are promising tools for rapid identification of NTM. Optimal therapy for a documented Mycobacterium gordonae infection remains undefined. The majority of isolates tested have been resistant in vitro to isoniazid and pyrazinamide, whereas many are susceptible to ethambutol, rifampin, clarithromycin, linezolid, and the fluoroquinolones. Unlike other nontuberculous mycobacteria, M. simiae produces niacin and thus may be confused with M. tuberculosis. M. simiae can colonize the respiratory tract, and the lung is the most commonly reported site of infection. The majority of reported infections have occurred in persons living near rivers or stagnant bodies of water. A recent open-label randomized trial conducted in Ghana compared two regimens for early, limited M. ulcerans infections. In this study, 73 of 76 patients who received streptomycin and rifampin for 8 weeks and 68 of 75 patients who received 4 weeks of streptomycin and rifampin followed by 4 weeks of rifampin and clarithromycin had healed lesions at 1 year after the start of treatment. Infections with M. xenopi have shown variable responses to drug therapy. Recommendations for initial therapy include isoniazid, a rifamycin, ethambutol, and clarithromycin with or without an initial course of streptomycin. Pyrazinamide and ciprofloxacin have been included in some successful regimens.

Tuberculosis (TB) continues to pose a significant public health problem worldwide. For mycobacteriology laboratories, it is important to be able to diagnose active cases and to make a differential diagnosis of non-tuberculous mycobacteria (NTM). In this study, it was aimed to retrospectively evaluate the epidemiological status of the Mycobacterium [Mycobacterium tuberculosis complex (MTC) and NTM] obtained from the clinical specimens of patients with TB suspicion, and the resistance rates of MTC isolates against anti-TB drugs. Various clinical samples of TB suspected patients sent to the Balikesir Ataturk City Hospital Mycobacteriology Laboratory between 2011 and 2019, were included in the study. Microscopy, culture procedures, and the first-line anti-TB drug susceptibility tests were performed according to the instructions. Identification of NTM at the species level could be made during four years including 2012, 2013, 2016, and 2017. In our study, acid fast bacillus (AFB) positivity rate was 4% (1.867/47.235); the culture positivity rate for MTC was 5.1% (1.576/31.017) and 1.1% (333/31.017) for NTM. AFB positivity was detected in 837 (53.1%) of the clinical specimens isolated from MTC. In the presence of AFB positivity, it was determined that bacterial growth was significantly higher in both liquid culture systems (LCS) and Lowenstein-Jensen (LJ) media. The isolation rate of MTC isolates from LCS was determined as 95.3% (1.503/1.576) and the isolation rate from LJ was 67.4% (1.063/1.576). The bacterial growth rate was found to be significantly higher in LCS. The average bacterial growth time (ABGT) of AFB negative samples were 21.79 ± 9.96 days; 13.74 ± 8.13 days for AFB positive samples, and ABGT was significantly shorter in the case of AFB positivity. As the severity of AFB positivity increased, ABGT wasshortened which was statistically significant. While 783 (78%) of the isolates were found to be sensitive to all the tested drugs, 221 (22%) were found to be resistant to at least one drug. Eleven of them (1%) were identified as multidrug resistant-TB (MDR-TB) isolates. In our study, 16 different species were identified among 112 typed NTM isolates. Mycobacterium gordonae (25.0%), Mycobacterium avium complex (17.0%) (Mycobacterium intracellulare-11.6%, Mycobacterium avium-5.4%) and Mycobacterium abscessus (13.3%) were the most frequently isolated NTM species. As a result, nine-year results of the mycobacteriology laboratory in our region were analyzed and the MTC and NTM epidemiological data were determined for the first time.

In this study, mycobacteria, which were previously identified as Mycobacterium tuberculosis complex (MTC), and mycobacteria other than tuberculosis (MOTT) with cord factor and the p‐nitro‐alpha‐acetyl‐amino‐beta‐hydroxypropiophenone (NAP) test were reanalysed using the polymerase chain reaction—restriction fragment length polymorphism (PCR‐RFLP) analysis method in order to confirm the identification, and at the same time, species accepted as MOTT were identified. Although the results of the NAP test were obtained within 3‐5 days, the PCR‐RFLP results were obtained in 1 day. Ten species identified as MTC with the NAP test and cord factor were confirmed with the PCR‐RFLP method. Fourteen species accepted as MOTT were identified as Mycobacterium species with the evaluation of the bands observed after the restriction of PCR product with the PCR‐RFLP method. These were as follows: three species Mycobacterium intracellulare type I, two species Mycobacterium phlei, two species Mycobacterium kansasii, one species Mycobacterium fortuitum type I, one species Mycobacterium gordonae type I, one species Mycobacterium abscessus type I, one species Mycobacterium scrofulaceum, one species Mycobacterium szulgai type I, one species Mycobacterium avium type II, and one species Mycobacterium terrae. Hence, the results of both the cord factor and the NAP test were confirmed with the molecular method, and at the same time, mycobacteria species identification was made by determining the fastest, easiest, and the most accurate result‐giving method. Because PCR‐RFLP is a very rapid method that provides exact identification of mycobacteria species, it can be performed in routine procedures.

L-asparaginase (E.C.3.5.1.1) is a well-known agent that prevents the formation of acrylamide both in the food industry and against childhood acute lymphoblastic leukemia in clinical settings. The disadvantages of L-asparaginase, which restrict its industrial application, include its narrow range of pH stability and low thermostability. In this study, a novel L-asparaginase from Mycobacterium gordonae (GmASNase) was cloned and expressed in Escherichia coli BL21 (DE3). GmASNase was found to be a tetramer with a monomeric size of 32 kDa, sharing only 32% structural identity with Helicobacter pylori L-asparaginases in the Protein Data Bank database. The purified GmASNase had the highest specific activity of 486.65 IU mg−1 at pH 9.0 and 50 °C. In addition, GmASNase possessed superior properties in terms of stability at a wide pH range of 5.0–11.0 and activity at temperatures below 40 °C. Moreover, GmASNase displayed high substrate specificity towards L-asparagine with Km, kcat, and kcat/Km values of 6.025 mM, 11,864.71 min−1 and 1969.25 mM−1min−1, respectively. To evaluate its ability to mitigate acrylamide, GmASNase was used to treat potato chips prior to frying, where the acrylamide content decreased by 65.09% compared with the untreated control. These results suggest that GmASNase is a potential candidate for applications in the food industry.

Nontuberculous mycobacteria (NTM) are environmental opportunistic pathogens of humans and animals that are emerging with a serious public health impact particularly in individuals with Acquired Immunodeficiency Syndromes. Recent scientific evidence is shifting from NTMs being known as traditional environmental organisms to serious pathogenic organisms in both animals and humans. In humans, factors attributable to this rise have been linked mainly to Human Immunodeficiency Virus and Acquired Immunodeficiency Syndrome pandemic. In recent years there has been an increase in multidrug resistant Tuberculosis in Zambia and it is thought that NTMs could possibly be the cause. This study was therefore formulated to review available information on the prevalence of NTM in humans, animals and the environment, species distribution, zoonotic potential and public health importance in Zambia. This review was conducted in accordance with PRISMA guidelines. A literature search was done in PubMed and Google scholar using predefined search terms such as ‘nontuberculous mycobacteria’, ‘atypical mycobacteria’, ‘mycobacteria other than mycobacterium tuberculosis’ and ‘Zambia’, in combination with Boolean operators (AND, OR). This particular systematic review draws findings based on literature search between 2000 and 2020. Through literature search 243 papers were identified, 23 duplicates were identified and removed and 206 articles were excluded as they did not meet the inclusion criteria. The full text of the remaining 14 articles were considered for this review. The overall prevalence of NTM in humans was 24.39%, in water 21.5%, in animals 16.05% of which the prevalence in cattle was 14.81% and Kafue Lechwe 1.23%. Mycobacterium intracellulare was the most common isolated nontuberculous mycobacteria in humans and cattle while Mycobacterium gordonae was the most common in water, and Mycobacterium stomatepiae sp Nov in Kafue Lechwe. Nontuberculous mycobacteria are an emerging public health threat in Zambia both in humans and animals and this calls for the need for molecular information on the zoonotic transmission of nontuberculous mycobacteria. Increased awareness of nontuberculous mycobacteria diseases among clinicians and laboratory personnel is crucial for patient management and an essential step for facilitating the identification of nontuberculous mycobacteria species in laboratories.

Made available in DSpace on 2022-04-28T17:22:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundacao Cearense de Apoio ao Desenvolvimento Cientifico e Tecnologico - FUNCAP Emerging infectious diseases in wild animals related to humans have received greater attention in recent years. Mycobacteriosis is a bacterial disease of animal and human importance. Mycobacterium gordonae infects the skin and internal organs of free-ranging amphibians and is considered the least pathogenic member of the Mycobacteriaceae to humans. However, information about its infection and pathogenesis in wild amphibians is still lacking. A total of 1306 amphibian specimens belonging to 6 families, 12 genera, and 21 species were collected and dissected during a helminthological survey of 7 municipalities in southern Ceara state, Caatinga (eco)region, northeast Brazil. Of these, 17 specimens (0.76%), belonging to 2 families and 4 species (Leptodactylus macrosternum, n = 2; L. vastus, n = 10; Pseudopaludicola pocoto, n = 2; Rhinella jimi, n = 3), presented infections that consisted of calcification nodules in the coelomic cavity, kidney, liver, lung, gut, and pancreas. The nodules were examined by histopathology and PCR. The bacteria were identified as M. gordonae by molecular analyses. Infected animals presented with hepatocellular vacuolar degeneration, karyolysis, and karyorrhexis, hepatic portal congestion, hemorrhage, mononuclear cellular infiltration, melanomacrophage center hyperplasia, and granulomas in varying stages of development with intralesional acid-fast bacilli. This study is the first report of M. gordonae in these amphibian species, in which results of molecular analyses confirmed the presence of M. gordonae in natural environments and histopathology confirmed the typical lesion of mycobacteriosis in amphibians from northeastern Brazil. Univ Fed Uberlandia UFU, Inst Ciencias Agr, BR-38500000 Monte Carmelo, MG, Brazil Univ Estadual Paulista UNESP, Dept Parasitol, Inst Biociencias, BR-18618970 Botucatu, SP, Brazil Univ Fed Ceara UFC, Ctr Reg Ophiol, BR-60455760 Fortaleza, Ceara, Brazil Univ Estadual Paulista UNESP, Dept Parasitol, Inst Biociencias, BR-18618970 Botucatu, SP, Brazil CNPq: 303622/2015-6 CNPq: 305988/2018-2 CNPq: 313241/2018-0 Fundacao Cearense de Apoio ao Desenvolvimento Cientifico e Tecnologico - FUNCAP: AEP-0128-00269.01.00/17 Fundacao Cearense de Apoio ao Desenvolvimento Cientifico e Tecnologico - FUNCAP: 05/2017

A slow-growing, scotochromogenic mycobacterial strain (24T) was isolated from the sputum of a Chinese male human. Phylogenetic analysis using the 16S rRNA gene assigned strain 24T to the Mycobacterium gordonae complex, which includes Mycobacterium gordonae and Mycobacterium paragordonae . The phenotypic characteristics, unique mycolic acid profile and the results of phylogenetic analysis based on hsp65 and rpoB sequences strongly supported the taxonomic status of strain 24T as a representative of a species distinct from the other members of the M. gordonae complex. The genomic G+C content of strain 24T was 65.40mol%. Genomic comparisons showed that strain 24T and M. gordonae ATCC 14470T had an average nucleotide identity (ANI) value of 81.00 % and a DNA–DNA hybridization (DDH) value of 22.80 %, while the ANI and DDH values between strain 24Tand M. paragordonae 49 061T were 80.98 and 22.80 %, respectively. In terms of phylogenetic, phenotypic and chemotaxonomic features, strain 24T is distinguishable from its closest phylogenetic relatives and represents a novel species of the genus Mycobacterium , therefore the name Mycobacterium vicinigordonae sp. nov. is proposed. The type strain is 24T (=CMCC 93559T=DSM 105979T).

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.

Background Nontuberculous mycobacterium (NTM) infection in a patient in an immunosuppressed state caused by increased use of immunosuppressive or biological agents is a serious clinical problem. Mycobacterium avium complex is the most common involved pathogen, followed by Mycobacterium abscessus (MABSC), while Mycobacterium kansasii is not a major concern. The rate of infection rate in lung transplant recipients is reported to range from 1.5–22.4%. Case presentation We report here four cases of NTM pulmonary infection and disease among 63 patients who underwent lung or heart-lung transplantation at our hospital. Those four occurred following living-donor transplantation in two patients, one with pulmonary arterial hypertension and one with bronchiectasia, and deceased donor lung transplantation in two patients, lymphangioleiomyomatosis and interstitial pneumonia, respectively. NTM was not detected in any of the patients prior to transplantation. The involved pathogens were Mycobacterium gordonae in one, MAC in one, and MABSC in two of these patients, which were isolated from broncho-alveolar lavage (BAL) in two and sputum in two. The one case of MAC and two of MABSC were symptomatic with consolidation shown in chest CT images indicating possible pneumonia, while the one with M. gordonae had no symptoms and was detected by surveillance BAL. Onset time from detection of NTM was greater than 3 years in the three with MABSC and M. gordonae and less than 3 years in the one with MAC. Each patient required a decrease in immunosuppressive agents according to their condition, while antibiotics therapy was performed in the three who were symptomatic. Sputum culture findings became negative after several months and were maintained thereafter in all. Conclusion An NTM infection leading to pulmonary disease can occur at any time following lung transplantation. Treatment should be considered depending on the involved pathogens, individual status, and disease severity.

In this study, we investigated the immune responses against Mycobacterium gordonae in ginbuna crucian carp. Cumulative mortality of ginbuna injected with 2.0 × 107 CFU of M. gordonae was 50% at 170 days post-infection. CD4-1, CD8α, T-bet and IFNγ2 gene expression levels were significantly upregulated in ginbuna injected with 1.9 × 108 CFU of M. gordonae at 21 and 28 days post-infection. The CD4-2 level did not change during the experiment. Granulomatous responses consisted of central macrophage accumulation and surrounding lymphocytes, and Ziehl-Neelsen-positive bacteria were observed in the trunk kidney of the challenged fish. Immunohistochemistry using anti-ginbuna IFNγs and anti-ginbuna CD4-1 polyclonal antibody revealed that the marginal lymphocytes were positive for CD4-1, and the IFNγ-producing cells surrounded the mycobacterial cell-laden phagocytes. These results suggest that CD4-1+ cells and IFNγ2 play important roles in the granulomatous inflammation against Mycobacterial infections in teleosts.

Background: Nontuberculous mycobacteria (NTM) have been identified in human pulmonary and extrapulmonary infections and are increasing globally, which makes it challenging to identify them. This article reports our experience with the laboratory identification of NTM in clinical practice among pulmonary and extrapulmonary samples received in our routine work. Methods: The study was conducted at the Universite Catholique de Louvain at the Cliniques Universitaires Saint-Luc, Brussels, Belgium, from 2015 to 2018. A total of 386 clinical samples were collected from patients suspected of having pulmonary or extrapulmonary mycobacterial infections. Routine laboratory methods phenotypic and molecular tests were performed. Results: The majority of NTM species were isolated from pulmonary samples (68%). The most prevalent species identified were Mycobacterium chimaera_intracellulare group (32%), followed by Mycobacterium avium complex (21%), Mycobacterium abscessus complex (18%), Mycobacterium gordonae (9%), and Mycobacterium chelonae (4%). In extrapulmonary samples, M. avium and M. chimaera_intracellulare were the most frequently isolated. Conclusion: The species diversity of NTM found in our setting suggests the importance of the use of new modern methods for accurate identification of NTM at species level and in some case at subspecies level for the proper treatment and management of patients.

A 46-year-old man visited our hospital with a fever and cough. The symptoms had started two months after continued use of an ultrasonic humidifier. He had hypoxemia on admission and late inspiratory crackles in both lungs on physical examination. The laboratory findings showed an increased white blood cell count and a C-reactive protein level, and his serum KL-6 level was slightly elevated, at 674 U/mL. Chest computed tomography showed diffuse ground-glass opacities, and histological examination of a transbronchial lung biopsy showed alveolitis without granulomas. The humidifier inhalation challenge test result was positive. Therefore, we diagnosed the patient with humidifier lung. His symptoms gradually improved after avoiding the humidifier without taking medication. The humidifier water was contaminated by various bacteria and fungi, as well as Mycobacterium gordonae and a high concentration of endotoxin. Unlike in those with typical hypersensitivity pneumonitis, the elevation of serum KL-6 levels in humidifier lung patients is mild, and granulomas are not apparent on histological examination, similar to our case. Furthermore, the endotoxin identified from the humidifier is one of the known pathogens of humidifier lung. Thus, humidifier lung seems to have different characteristics compared to other hypersensitivity pneumonitis phenotypes. The mechanism driven by the high concentration of endotoxin could be one of the main causes of humidifier lung.

Mastitis is a common disease in women with both infectious and noninfectious causes. Most cases occur during lactation and are caused by Staphylococcus aureus and Streptococcus species; parasites and Mycobacteria have rarely been reported to cause breast infections (Mandell, Douglas, and Bennett's principles and practice of infectious diseases (9th edn);2019, Am J Respir Crit Care Med. 2007;175:367). Nontuberculous mycobacteria (NTM) which are also referred to as atypical mycobacteria, mycobacteria other than tuberculosis (MOTT), or environmental mycobacteria are a large group of Mycobacteria which are becoming increasingly common cause of infection all over the world (Arch Dermatol. 2006;142:1287). NTM can cause infection diseases especially in immunocompromised patients, such as HIV-positive hosts, most commonly in the lungs, skin and soft tissue, lymph nodes or rarely spread with multiorgan dissemination (Arch Plast Surg. 2014;41:759). Mycobacterium gordonae (M. gordonae) is a slow-growing atypical mycobacterium that is considered the least pathogenic NTM. The organism is ubiquitous, and mostly isolated from soil and water. Despite its nonvirulent nature, clinically significant infections have been reported also in some immunocompetent patients (J Formosan Med Assoc. 2020, Clin Infect Dis. 1992;1229). We report the first documented case of breast infection in a young immunocompetent woman sustained by Mycobacterium Gordonae.

SUMMARY Objective The international outbreak of cardiac-surgery-associated Mycobacterium chimaera infections was traced back to infectious aerosols originating from contaminated water reservoirs of heater-cooler devices (HCDs). In general, non-tuberculous mycobacteria (NTM) frequently colonize water systems and can contaminate medical devices. Data on detection of NTM other than M. chimaera in samples gathered from HCDs are scarce. The present study summarizes prospective mycobacterial surveillance of five HCDs over more than 4 years. Methods Five LivaNova 3T (London, UK) HCDs, acquired factory-new in 2014, were followed prospectively. Until mid-April 2014, the HCDs were maintained according to the manufacturer's recommendations, and subsequently, they were maintained according to an intensified in-house protocol including exhaust air evacuation. Mycobacterial surveillance cultures consisted of monthly water samples gathered from patient and cardioplegia circuits, as well as airflow samples. Results Of 441 water samples, 170 (38.6%) revealed NTM growth. The most frequently detected NTM were M. chimaera [N=120 (67.4%)], Mycobacterium gordonae [N=35 (19.7 %)] and Mycobacterium paragordonae [N=17 (9.6%)]. Growth of NTM, M. chimaera and M. paragordonae was significantly more common in water samples derived from the patient circuit than the cardioplegia circuit of the HCD. Three (2.0%) of 150 air samples grew NTM. Conclusion Growth of NTM in HCD water samples was common. Diverse NTM species were detected, with M. chimaera being the most common. The majority of air samples remained negative. The relevance of NTM other than M. chimaera contaminating HCDs is poorly defined, but a recent report on an HCD-associated outbreak with Mycobacterium abscessus confirmed a potential threat.

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.

Acanthamoeba is an opportunistic protozoon, widespread in the aquatic environment, where it can be in endosymbiosis with over 30 pathogenic bacteria, including nontuberculous mycobacteria (NTM). Protozoa play a crucial role in mycobacterial pathogenesis and serve as a reservoir of infection. Since the first step in bacteria making contact with amoebae is adhesion, we were interested in investigating whether essential oils (EOs) can affect it. To that end we investigated the effects of juniper (Juniperus communis) and immortelle (Helichrysum italicum) EOs against Mycobacterium avium, M. intracellulare, and M. gordonae in tap water and against their adhesion to Acanthamoeba castellanii by combining them in synergistic EO concentrations. M. avium and M. intracellulare adhered to A. castellanii to a greater extent than M. gordonae. The adhesion of all NTMs was prevented by the subinhibitory concentrations of EOs. When comparing the effect of synergistic combinations of EOs and the effect of a single concentration from a combination, a higher percentage of adhesion inhibition in all synergistic combinations observed, except against M. gordonae. Neither oil was cytotoxic to A. castellanii. Our findings suggest that the EOs or their components weaken the contact of environmental NTMs and free-living amoebae and indirectly diminish their pathogenic potential, which could be of value in developing strategies for maintenance of water supply systems., Akantameba je oportunistička protozoa, široko rasprostranjena u vodenom okružju, gdje može kao endosimbionte sadržavati više od 30 različitih patogenih bakterija, uključujući netuberkulozne mikobakterije (NTM). Protozoe kao rezervoar infekcije imaju ključnu ulogu u mikobakterijskoj patogenezi. Sposobnost mikobakterija da se vežu, ulaze I umnožavaju se unutar protozoa vjerojatno im je omogućila da postanu intracelularni patogeni. Budući da je adhezija prvi korak u uspostavi kontakta bakterija s amebama, zanimalo nas je istražiti mogu li prirodni spojevi poput eteričnih ulja utjecati na taj kontakt. Cilj ove studije bio je istražiti učinak eteričnih ulja borovice (Juniperus communis) i smilja (Helichrysum italicum) prema NTM-ovima (M. avium, M. intracellulare i M. gordonae) u pitkoj vodi. Također, ispitana je mogućnost inhibicije adhezije tih NTM-ova na Acanthamoeba castellanii (A. castellanii) primjenom sinergijskih koncentracija eteričnih ulja. M. avium i M. intracellulare, u odnosu na M. gordonae, u većoj su mjeri adherirali na A. castellanii. Adhezija svih NTM-ova inhibirana je subinhibicijskim koncentracijama eteričnih ulja borovice i smilja. Kad se usporedi učinak sinergijskih kombinacija i učinka pojedine koncentracije iz sinergije, uočen je veći postotak inhibicije adhezije kod primjene svih sinergijskih kombinacija, osim jedne prema M. gordonae. Oba eterična ulja u ispitivanim koncentracijama nisu imala citotoksično djelovanje na stanice A. castellanii. Na taj su način primijenjene subinhibicijske koncentracije eteričnih ulja sa smanjenim toksičnim učinkom, uz zadržan antimikrobni i antiadhezivni učinak. Primjena eteričnih ulja ili njihovih komponenata u umjetnom vodenom okolišu mogla bi oslabiti kontakt NTM-ova i slobodno živućih ameba i posredno dovesti do smanjenja patogenoga potencijala okolišnih NTM-ova.

WOS: 000453790600009, PubMed: 30010392, The typing of non-tuberculous mycobacteria (NTM) is important from a clinical and epidemiological perspective. The polymerase chain reaction-restriction enzyme analysis (PRA) method and DNA sequence analysis method were utilized to target a gene region that codes the 65-kDa heat-shock protein for typing 150 suspected NTM samples isolated from the respiratory tract. Mycobacterium abscessus, Mycobacterium xenopi, Mycobacterium fortuitum, and Mycobacterium peregrinum were most frequently found by both methods. Six isolates that could not be defined by the PRA method were defined as Nocardia cyriacigeorgica, Nocardia abscessus, and Mycobacterium intracellulare by DNA sequence analysis. Discordance between the results of the two methods was observed for only one isolate. The isolate that was defined as Mycobacterium gordonae type 6 by the PRA method was defined as Mycobacterium senegalense by sequence analysis. The PRA method is simple and gives rapid results. Compared with DNA sequence analysis, it gives consistent and reliable results up to a ratio of 90%. DNA sequence analysis is the gold standard method in which all strains can be defined. However, given our laboratory conditions, its disadvantage is that it takes longer to reach a diagnosis than through the PRA method.

Background Ataxia telangiectasia (AT) is a rare, multi-systemic, genetic disorder. Mutations in the ATM gene cause dysfunction in cell-cycle, apoptosis and V (D) J recombination leading to neurodegeneration, cellular, humoral immunodeficiencies and predisposition to malignancies. Previous studies have suggested that a sub-group of AT patients with elevated IgM levels have a distinct and more severe phenotype. In the current study we aimed to better characterize this group of patients. Methods We performed a retrospective review of 46 patient records, followed from January 1986 to January 2015 at the Israeli National AT Center. Demographic, clinical, radiological, laboratory data was reviewed and compared between AT patients with elevated IgM levels (EIgM) and patients with normal IgM levels (NIgM). Results 15/46(32.6%) patients had significantly elevated IgM levels. This group had a unique phenotype characterized mainly by increased risk of infection and early mortality. Colonization of lower respiratory tract with Mycobacterium gordonae and Pseudomonas aeruginosa as well as viral skin infections were more frequent in EIgM patients. Patients with NIgM had a significantly longer survival as compared to patients with EIgM but had an increased incidence of fatty liver or cirrhosis. T-cell recombination excision circles and kappa-deleting element recombination circle levels were significantly lower in the EIgM group, suggesting an abnormal class switching in this group. Conclusions EIgM in AT patients are indicative of a more severe phenotype that probably results from a specific immune dysfunction. EIgM in AT should be considered a unique AT phenotype that may require different management. Electronic supplementary material The online version of this article (10.1186/s12887-018-1156-1) contains supplementary material, which is available to authorized users.

Previous studies have identified patients infected with Mycobacterium chimaera (M. chimaera) subsequent to cardiac surgery. Water tanks in heater-cooler units (HCUs) used cardiac heart surgery was traced as source. The aim was to investigate occurrence of M. chimaera and other microorganisms in HCUs and evaluate the silver-ion cleaning routine.Five HCUs were disinfected with silver-ions and examined for mycobacteria directly (15 min) after the disinfection procedures and later on three occasions (3, 6, 10 weeks). One HCU was selected for additional investigation of the presence of other microorganisms. In addition, tap water from five sinks in the surgical department was examined for the presence of mycobacteria and other microorganisms.M. chimaera grew in all the HCU water tanks and in 35 of the 40 HCU samples. Three of the samples also contained Mycobacterium gordonae. When the selected HCU tanks were analysed directly after the disinfection procedure bacteria and fungi were found but no non-fermenting Gram-negative rods. These HCU samples contained a doubled to 3 fold amount of bacteria compared to initial tap water samples. No mycobacteria were found in any sample from the five water taps.The silver-ion cleaning routine was insufficient and M. chimaera was found in all HCUs. However, no mycobacteria were found in any sample from the five water taps suggesting another source of colonization. It is probable that residual water and biofilm are of importance. Our results emphasize the need for improved disinfection procedures and improved construction of the HCUs.

Background Nontuberculous Mycobacteria (NTM) are environmental microorganisms that can affect human health. A 2009–2010 occurrence survey of NTM in potable tap water samples indicated an increased recovery rate for many clinically significant species such as M. avium (30%) and M. abscessus (12%). To determine if these trends by species were mirrored in human infections, isolation rates of NTM species identified in clinical laboratory reports from four states were evaluated. Method Clinical laboratory reports from the Mississippi, Missouri, Ohio, and Wisconsin Health Departments were used to investigate the species of NTM isolated from human specimens in 2014. The NTM positive specimen reports were tabulated for each species and complex/group. The number of reports by month were used to investigate seasonal trends. The 2014 isolation rates were compared to historic values to examine longitudinal trends. Results The positive rate of NTM specimens increased from 8.2 per 100,000 persons in 1994 to 16 per 100,000 persons in 2014 (or 13.3 per 100,000 after excluding Mycobacterium gordonae). Changes in NTM diversity were observed in complex/groups known to be clinically significant. Between 1994 and 2014 the rate implicating M. abscesses-chelonae group and M. avium complex increased by 322 and 149%, respectively. Conclusions Based on public health data supplied by the four State’s Health Departments and the 2014 U.S. population, 50,976 positive NTM specimen reports per year were projected for the nation; serving as an indicator for the national potential disease burden that year. Electronic supplementary material The online version of this article (10.1186/s12879-018-3043-7) contains supplementary material, which is available to authorized users.

Background: There is evidence that drinking water could be a source of infections with pathogenic nontuberculous mycobacteria (NTM) potentially risky to human health. The aim was to investigate the resistance of two NTM isolated from drinking water, Mycobacterium gordonae and Mycobacterium chubuense, at different concentrations of chlorine (as sodium hypochlorite), used in drinking water sanitation. Methods: The NTM were grown in suspension and in biofilms and were challenged with biocide for 10 and 60 min. Results: To obtain 7-log reduction from the initial population of M. chubuense, in the planktonic state, there were necessary 20 ppm of chorine and 60 min of exposure. The same effect was achieved in M. gordonae with 10 ppm for the same period. The maximum reduction of both NTM in biofilm was 3-log reduction and was achieved using 30 ppm for 60 min. The chlorine susceptibility of cells in biofilms was significantly lower than that of planktonic cells. The results highlight the resistance of both NTM to the concentrations used in routine water sanitation (0.2 ppm according to Argentine Food Code). Differences in chlorine resistance found between the two NTM in planktonic growth decrease when they are grown in biofilm. Conclusion: This suggests that current water disinfection procedures do not always achieve effective control of NTM in the public supply system, with the consequent health risk to susceptible population, and the need to take into account biofilms, because of their deep consequences in the way to analyze the survival of prokaryotic cells in different environments.

We evaluated PyroMark Q24 (QIAGEN) pyrosequencing as a method for the identification of mycobacteria, with potential application in clinical practice. Sequence data from the hypervariable region A of the 16S rRNA gene (43 and 35bp sequences) were obtained using PyroMark Q24, and a similarity search was performed automatically with PyroMark IdentiFire software. Of the 148 mycobacterial type strains tested, 138 (93.2%) were accurately identified to single or clade species level, including complex level. From the remaining 10 strains, 3 (Mycobacterium gilvum, Mycobacterium goodi, and Mycobacterium thermoresistible) showed poor sequencing quality of homopolymers. For 6 other strains (Mycobacterium cosmeticum, Mycobacterium flavescens, Mycobacterium pallens, Mycobacterium hodleri, Mycobacterium xenopi, and Mycobacterium crocinum), the sequences were unreadable from the middle, and Sanger sequencing indicated biallelic site. Finally, a 40bp sequence for Mycobacterium gordonae could not be obtained despite repeated attempts. PyroMark Q24 provided accurate identification of multiple mycobacterial strains isolated from common clinical settings, but additional gene sequencing is required to distinguish species identified as a group or complex.