Identification and characterization of nontuberculous mycobacteria isolated from suspected pulmonary tuberculosis patients in eastern china from 2009 to 2019 using an identification array system

ObjectiveNontuberculous mycobacteria (NTM) species are increasingly being isolated and have become a key factor affecting public health by causing pulmonary diseases. Most NTM species do not respond to conventional tuberculosis (TB) drugs. This study aimed to identify NTM isolated from suspected pulmonary TB patients from the Zhejiang province and analyze their distribution in the region.MethodsA total of 1,113 NTM isolates from patients suspected to be suffering from acid-fast bacilli-positive tuberculosis were identified at the species level, using the CapitalBio Mycobacterium identification array and polymerase chain reaction amplification and sequencing of 16S-23S gene internal transcribed spacer (ITS), 16S rRNA, and hsp65.ResultsOf the 23,138 isolates, we identified 1,102 NTM (4.8%), mainly including Mycobacterium intracellulare (54.81%, 604/1,102), M. chelonae-M. abscessus (16.52%, 182/1,102), M. avium (13.16%, 145/1,102), M. kansasii (8.17%, 90/1,102), and M. gordonae (3.27%, 36/1,102).ConclusionThe distribution of NTM species observed in patients with suspected pulmonary tuberculosis provides guidance for the diagnosis and treatment of NTM pulmonary diseases.     

Regional differences of nontuberculous mycobacteria species in Ulsan,Korea

Background

In Korea recently, nontuberculous mycobacteria (NTM) have been more frequently isolated in respiratory specimens, while Mycobacterium tuberculosis (MTB) isolations have decreased. The major NTM lung disease species in Korea are M. intracellulare, M. avium, and M. abscessus, whereas M. kansasii is a rare species. This retrospective study was performed to determine if there are region-specific characteristics of lung disease-causing NTM species in Ulsan, a highly industrialized city in Korea.

Methods

Between January 2010 and July 2013, the results of all acid-fast bacilli (AFB) cultures of respiratory specimens performed at Ulsan University Hospital (Ulsan, Korea) were collected. NTM were identified and regional differences of NTM species were compared.

Results

AFB cultures were performed on 33,567 respiratory specimens, obtained from 10,208 patients, during the study period. Further, 10% of the specimens (3,287/33,567) were AFB culture-positive [MTB, 2,288/3,287 (70%); NTM 999/3,287 (30%)]. The proportion of NTM isolations gradually increased between 2010 and 2013, at 25% and 38%, respectively. The most common NTM species was M. intracellulare (356/999, 36%), followed by M. kansasii (295/999, 30%), M. avium (161/999, 16%), M. abscessus (117/999, 12%) and M. fortuitum (39/999, 4%). This trend was maintained throughout the study period.

Conclusions

In Ulsan, NTM isolation from respiratory specimens is increasing, consistent with previous studies performed in Korea. The distribution of respiratory NTM species, however, differed from previous studies that were performed in other regions of Korea: M. kansasii was the second most common NTM species in Ulsan. In Ulsan, there is a regional difference in the NTM species isolated.     

Genetic and serovar typing of clinical isolates of the Mycobacterium avium-intracellulare complex

Setting: One hundred and thirty-four Mycobacterium avium-intracellulare complex (MAC) isolates were obtained from 121 patients in the UK.Objective: To compare serotyping and genetic analysis for species identification of MAC isolates from patients with and without the acquired immunodeficiency syndrome (AIDS).Design: Clinical MAC isolates were cultured and analyzed by serotyping, the commercially available Accuprobe kit, hybridization with genes coding for the 19 kDa and 38 kDa antigens of M. tuberculosis and fingerprinting with the pMB22 probe derived from M. paratuberculosis.Results: Species classification on the basis of genetic analysis was similar to serovar typing, with only exceptional discrepancies. Serovar prevalence was different in the two groups of patients, and different from those reported in other countries. MAC isolates from AIDS patients were exclusively M. avium, whereas patients without AIDS had MAC infections with M. avium and M. intracellulare in about equal proportion. M. intracellulare clinical isolates were genetically more heterogeneous than M. avium. Only M. intracellulare hybridized with the 38 kDa gene probe.Conclusions: Serovars are strongly linked with species in clinical MAC isolates, confirming results previously obtained with reference strains. M. intracellulare can be easily identified by the presence of a 38 kDa gene.     

Mycobacterium avium‐intracellulare‐associated acute interstitial nephritis: a rare cause of renal allograft dysfunction

Abstract: Nontuberculous mycobacterium (NTM) infections are unusual in the renal transplant population. We present a case of disseminated Mycobacterium avium‐intracellulare in a renal transplant recipient who was negative for human immunodeficiency virus infection. Our patient developed renal allograft dysfunction in the setting of disseminated disease and reduced immunosuppression. Transplant biopsy showed acute interstitial nephritis with granulomas and acid‐fast bacilli. Acute renal failure resolved completely with further reductions in immunosuppression and anti‐mycobacterial therapy. Our patient demonstrates the challenges in diagnosis and treatment of this rare infectious complication.     

Non-tuberculous Mycobacterial Pseudo-outbreak of an Intestinal Culture Specimen Caused by a Water Tap in an Endoscopy Unit

Objective Gastrointestinal lesions of non-tuberculous mycobacteria (NTM) are regarded as opportunistic infections. A large number of positive specimens of NTM were identified in an intestinal fluid culture in the endoscopy unit and it was considered to be a pseudo-outbreak. Methods We reviewed the hospital, laboratory, and colonoscopy records of 263 consecutive patients whose intestinal fluids were analyzed for a mycobacterial culture by colonoscopy at St. Marianna University Hospital, between January 2009 and December 2018. The endoscopy reprocessing procedures were reviewed and samples of water used in the endoscopy unit were cultured. Results An intestinal fluid culture of 154 (58.6%) patients tested positive for NTM (M. intracellulare; 125 cases, M. gordonae; 14 cases, M. avium; 4 cases, M. abscessus; 3 cases, and 8 other cases). In 182 cases (69.2%), an intestinal mucosal culture was performed simultaneously with a fluid culture and tested positive for NTM in 2 cases. Next, we examined the endoscopy unit for any possible environmental contamination. NTM were detected in the tap water used to prepare the antifoaming solution in the endoscopy unit. The water faucets in the endoscopy unit were considered to be the source of the contamination of NTMs. Conclusion We observed that a large number of cases tested positive due to contaminated water that had been used in an endoscopy unit, thus leading to a pseudo-outbreak of NTM.     

Infecciones cutáneas y de partes blandas por micobacterias no tuberculosas

The frequency of isolation as well as the number of species of non-tuberculous mycobacteria (NTM) has increased in the last years. Nearly every pathogenic species of NTM may cause skin and soft tissue infections, but rapidly growing mycobacteria (Mycobacterium fortuitum, Mycobacterium chelonae and Mycobacterium abscessus), Mycobacterium marinum and Mycobacterium ulcerans are the most commonly involved. Many of these cutaneous mycobacteriosis, such as rapidly growing mycobacteria, M. marinum, Mycobacterium avium complex, Mycobacterium kansasii or Mycobacterium xenopi are world-wide distributed. In contrast, some others have a specific geographical distribution. This is the case of M. ulcerans, which causes a cutaneous diseases endemic of Central and West Africa (Buruli ulcer) and Australia (Bairnsdale ulcer), being the third mycobacterial infection after tuberculosis and leprosy. Cutaneous mycobacteriosis usually appear either after contact of traumatic or surgical wounds with water or other contaminated products, or, secondarily, as a consequence of a disseminated mycobacterial disease, especially among immunosuppressed patients. For an early diagnosis, it is necessary to maintain a high degree of suspicion in patients with chronic cutaneous diseases and a history of trauma, risk exposure and negative results of conventional microbiological studies. In general, individualized susceptibility testing is not recommended for most NTM infections, except for some species, and in case of therapeutic failure. Treatment includes a combination of different antimicrobial agents, but it must be taken into account that NTM are resistant to conventional antituberculous drugs. Severe cases or those with deep tissues involvement could also be tributary of surgical resection.     

Nontuberculous mycobacterial lung disease in patients without HIV infection: a retrospective analysis over 3 years

Introduction: Nontuberculous mycobacterial lung infections are relatively common in immunocompromised patients but are now increasingly being diagnosed in immunocompetent individuals. These organisms are not always pathogenic bacteria when isolated from human samples. The identification of which isolates are contaminants or colonizers is based on internationally accepted criteria. The clinical significance of the isolation of nontuberculous mycobacteria (NTM) from respiratory specimens in Italy is unknown. Objective: study was performed to evaluate the local epidemiology of NTM pulmonary infection in Naples in patients with positive respiratory specimens, and also to describe the clinical and radiological features of NTM pulmonary disease in immunocompetent patients with or without pre‐existing lung disease. Methods: Between December 2006 and September 2009, the clinical records and radiological examinations of 39 patients with 55 positive cultures for NTM species by sputum or bronchial wash or lavage were reviewed. Results: According to microbiological, clinical and radiological criteria, our study identified 16 patients with NTM lung infection as a ‘disease’ group and 23 patients in a ‘contamination’ group but without disease. M. intracellulare (n = 7, 41.2%), followed by M. kansasii (n = 5, 29.4%) were the most common NTM found in the ‘disease’ group. We detected a high number of M. gordonae isolates in respiratory samples obtained by fibrobronchoscopy. Conclusions: We evaluated the clinical significance of isolations in our reference centre in Naples. Forty‐one of all patients have ‘disease’, M. intracellulare and M. kansasii are mainly responsible. NTM species were analyzed in relation to their frequency. Assumptions were made about low pathogenic NTM isolations. Please cite this paper as: Del Giudice G, Iadevaia C, Santoro G, Moscariello E, Smeraglia R and Marzo C. Nontuberculous mycobacterial lung disease in patients without HIV infection: a retrospective analysis over 3 years. Clin Respir J 2011; 5:203–210.     

Infektionen mit nichttuberkul?sen Mykobakterien bei Patienten mit Immundefekten

Infections caused by nontuberculous mycobacteria (NTM) cause a variety of clinical pictures, like nodular or cavitary lung infiltrations, lymphadenitis or lesions of the skin and soft tissue. In patients with innate or acquired immune deficiencies, an increase of disseminated but also local, atypical disease manifestations is observed. Detailed knowledge about underlying immune defects and the current immune status of patients with suspected NTM infections is indispensable to verify the detection of NTM in clinical specimens which does not necessarily account for a direct disease association. Differences in the growth kinetics of bacteria from the M. avium complex (MAC) which primarily cause lung diseases in contrast to the rapidly growing M. fortuitum and M. chelonae (RGM) involved in skin and soft tissue infections have to be considered in the diagnostics of NTM infections. Emergence of treatment strategies including biologicals in chronic inflammatory diseases resulted in an increase of local and disseminated NTM infections in the past. The duration of NTM treatment may be prolonged in patients with underlying immune deficiencies and disseminated infections. NTM prophylaxis should be discussed in HIV/AIDS patients with severe immune deficiency (CD4 ?<?50/??l) starting with antiretroviral therapy (cART) as NTM infections presenting as lymphadenitis are frequently observed in patients with immune reconstitution inflammatory syndrome (IRIS).     

Clinical significance and epidemiologic analyses of Mycobacterium avium and Mycobacterium intracellulare lung disease from post-marketing surveillance

Background

In Japan, nontuberculous mycobacterial lung disease is mostly attributable to Mycobacterium avium complex (MAC), i.e., M. avium or M. intracellulare. However, clinical features of the disease caused by these two pathogens have not been studied sufficiently yet.

Nontuberculous mycobacterial pulmonary infections

Pulmonary infections due to nontuberculous mycobacteria (NTM) are increasingly recognized worldwide. Although over 150 different species of NTM have been described, pulmonary infections are most commonly due to Mycobacterium avium complex (MAC), Mycobacterium kansasii, and Mycobacterium abscessus. The identification of these organisms in pulmonary specimens does not always equate with active infection; supportive radiographic and clinical findings are needed to establish the diagnosis. It is difficult to eradicate NTM infections. A prolonged course of therapy with a combination of drugs is required. Unfortunately, recurrent infection with new strains of mycobacteria or a relapse of infection caused by the original organism is not uncommon. Surgical resection is appropriate in selected cases of localized disease or in cases in which the infecting organism is resistant to medical therapy. Additionally, surgery may be required for infections complicated by hemoptysis or abscess formation. This review will summarize the practical aspects of the diagnosis and management of NTM thoracic infections, with emphasis on the indications for surgery and the results of surgical intervention. The management of NTM disease in patients with human immunodeficiency virus (HIV) infections is beyond the scope of this article and, unless otherwise noted, comments apply to hosts without HIV infectionKEYWORDS : Nontuberculous mycobacterium (NTM), mycobacterium avium intracellulare (MAI), bronchiectasis, mycobacterium abscessus, hot tub lung     

Utilización de diferentes técnicas de biología molecular integradas en un algoritmo de identificación de micobacterias no tuberculosas

Introduction

The aim of the present work was to demonstrate the utility of a non-tuberculous mycobacteria (NTM) identification algorithm, which integrates different PCR-based techniques and basic phenotypic features. Moreover, the algorithm for pattern restriction analysis of hsp65 (hsp65 PRA) interpretation has been updated.

Methods

The workflow chosen consisted of the identification by a DNA hybridization probe method, followed by PCR-restriction enzyme analysis of hsp65 (hsp65 PRA) in those isolates that cannot be identified by hybridization probes. If necessary, 16S rRNA gene and hsp65 gene sequencing were used for speciation.

Results

A total of 236 NTM were collected, in which 102 (43.2%) isolates were identified by DNA specific probes and 76 (32.2%) isolates were identified with hsp65 PRA. Partial sequencing of the 16S rRNA gene was used for species identification of the remaining 58 (24.5%) isolates. Fifty-three (22.4%) were identified using this method. Five isolates (2.1%) were submitted for partial sequencing of hsp65 gene and one isolate was identified with this method. Four strains (1.7%) could not be identified at species level. Three new PRA patterns were found. Seven isolates tested positive with the AccuProbe Mycobacterium avium complex identification test but did not test positive with the M. avium or Mycobacterium intracellulare specific probes. Five and two of these isolates were identified as M. intracellulare and Mycobacterium colombiense, respectively.

Conclusion

This approach allowed us to identify almost all NTM isolates found in this study, including some recently described species.     

Identification of Mycobacterium avium complex strains belonging to serovars 21–28 by three commercial DNA probe tests

Various reference strains of Mycobacterium avium complex (MAC) belonging to serovars 21–28 were identified by three DNA probe tests, i. e., Gen-Probe ^®, AccuProbe^™ and SNAP^® tests. All of these DNA probe tests were in agreement for strains identified as M. aviumor M. intracellulare. The tested serovar strains involved M. avium, M. intracellulare, MAC reactive only with Probe X of SNAP test (‘Probe X-reactive MAC’), M. scrofulaceum reactive with Probe X of SNAP test (‘Probe X-reactive M. scrofulaceum’), and typical M. scrofulaceum which did not react with any of the probes. Both reference strains belonging to serovar 21 were M. avium, and none of the other serovars included this species. On the contrary, M. intracellulare was found in serovars 22, 25, 26, and 28. ‘Probe X-reactive MAC’ were also widely found in serovars 23, 24, 26, 27, and 28, while ‘Probe X-reactive M. scrofulaceum’ was seen only in serovar 22. These results confirm the usefulness of SNAP test to identify the MAC showing no reactivity to Gen-Probe and AccuProbe.     

Non tuberculosis mycobacteria isolates among new and previously treated pulmonary tuberculosis patients in Nigeria

ObjectiveTo determine the prevalence of non tuberculosis mycobacteria (NTM) among new and previously treated tuberculosis (TB) patients in Nigeria.MethodsIt was a retrospective study. A total of 102 sputum smear positive samples/culture isolates from pulmonary TB patients (41 new smear positive and 61 smear positive retreatment cases) were sent to the Institute of Tropical Medicine, Antwerp Belgium between 2007-2009. Data on patients' characteristics were retrieved from their treatment cards.ResultsAmong the 102 samples, 25 isolates results (20 were culture negative while 5 were contaminated) were excluded from the study. Data were available for 77 mycobacterium isolates. 70 (90.9%) were identified as Mycobacterium tuberculosis and 7 (9.1%) as atypical mycobacteria. Among the atypical mycobacteria, three of them were Mycobacterium fortuitum, two Mycobacterium intracellulare and two Mycobacterium chelonae. Of the seven isolates with atypical mycobacteria, 4 (57.1%) were from previously treated patients, while 3 (42.9%) were new sputum positive patients. There was no statistically significant difference in NTM infection between new and previously treated pulmonary TB patients (P =0.97).ConclusionsThe study shows the involvement of atypical mycobacterium in pulmonary infection in both new and previously treated TB patients. Therefore, there is a need to carry out culture and drug susceptibility testing in all pulmonary TB patients especially those who had failed conventional DOTS treatment to rule out NTM infections.     

Therapeutic effect of KRM-1648 with various antimicrobials against Mycobacterium avium complex infection in mice

A new benzoxazinorifamycin, KRM-1648 (KRM), was studied for its therapeutic efficacy in combination with other antimicrobials against Mycobacterium avium complex infections in mice. When M. intracellulare-infected (intravenously) mice were given KRM, clarithromycin (CAM), sparfloxacin (SPFX), or ethambutol (EB) each alone or in combination, by gavage, once daily 6 times per week (streptomycin [SM]was given subcutaneously twice per week) from day 1, KRM + CAM exhibited combined efficacy in terms of reducing the incidence of gross lung lesions and the bacterial loads in the lungs and spleens. The addition of either EB or EB + SPFX to KRM + CAM increased the efficacy. Moreover, the multi-drug regimen of KRM + CAM + EB + SPFX (or ofloxacin [OFLX]) was more efficacious than rifampicin (RMP) + CAM + EB + SPFX (or OFLX). In M. avium infection, KRM + clofazimine was the most efficacious among two-drug combinations tested followed by KRM + SM. KRM + CAM was considerably less effective against M. avium than against M. intracellulare infection. KRM + EB and KRM + OFLX failed to show such a combined effect.     

Increased risk of nontuberculous mycobacterial infection in asthmatic patients using long-term inhaled corticosteroid therapy

Background and objective: The risk of pneumonia is increased among COPD patients using inhaled corticosteroids (ICS). However, there is uncertainty regarding the association between long‐term use of ICS and exacerbations of respiratory tract infections among asthmatic patients. Methods: A case‐control nested cohort study was performed to assess the association of asthma with nontuberculous mycobacterium (NTM) infection. Results: Among this cohort of 464 asthmatic patients, 14 experienced complications due to NTM infections, of which eight were caused by Mycobacterium avium‐intracellulare complex, three by M. kansasii, one by M. terrae and the remaining two by unclassifiable scotochromogens. Asthmatic patients with NTM infections were older (67.1 ± 8.6 vs 58.8 ± 12.3 years, P < 0.01) and had more severe airflow limitation (FEV₁%, 60.6 ± 10.3 vs 72.3 ± 18.3, P < 0.03) than those without NTM infections. All except one had received ICS treatment for more than 5 years, and 12 of the 14 patients used inhaled fluticasone propionate daily (four patients at a dose of 400 µg/day and eight patients at a dose >800 µg/day). Conclusions: These findings suggest that the risk of NTM infection may be greater in asthmatic patients who are older, have more severe airflow limitation and receive higher doses of ICS therapy.     

Identification and Characteristics of Co-isolation of Multiple Nontuberculous Mycobacteria

Objective Although multiple nontuberculous mycobacteria (NTM) species can be isolated from the same patient, little has been reported on co-isolation. We clarified the trends and characteristics of the co-isolation of multiple NTM species. Methods To collect data on multiple NTM isolation, we first extracted all patients who visited our hospital from 2006 through 2015 with a diagnosis of NTM lung diseases other than Mycobacterium avium complex (MAC) and then reviewed their medical records to evaluate the co-isolation of multiple NTM species. Results Of 213 patients with non-MAC lung disease, the most common NTM species was M. gordonae (32%), followed by M. kansasii (20%) and M. abscessus (14%). Non-MAC NTM lung disease tended to be associated with middle age with a low body mass index and male predominance. Multiple NTM species were isolated from 55 (26%) of the 213 patients. The clinical characteristics associated with multiple NTM species isolation included female predominance, never smokers and the absence of cavity lesions in the lungs. The highest co-isolation rate was observed in patients with M. gordonae isolation (30%), followed by M. furtuitum isolation (26%) and M. abscessus isolation (20%). Only MAC was isolated when co-isolated with M. abscessus. Among M. szulgai, M. peregrinum and M. terrae isolation, no other NTM species were detected. Conclusion Co-isolation of multiple NTM species was not uncommon, with 26% of patients with non-MAC NTM lung diseases showing co-isolation with multiple NTM species. Each NTM species had distinct characteristics in terms of co-isolation.     

Six years' experience with the discontinuation of BCG vaccination: 4. Protective effect of BCG vaccination against the Mycobacterium avium intracellulare complex

Setting: In 1986, mass BCG vaccination of newborns was discontinued in an extensive territorial sample of neonates in the Czech Republic (30 000 infants annually). The non-vaccinated children have since been tuberculin tested at two-year intervals; those with continual or repeated intensive contact with animals in households or on farms were also tested with Mycobacterium avium intracellulare complex sensitin in addition to tuberculin.Objective: Within the frame work of the surveillance programme the incidence of infection and disease caused by M. avium intracellulare complex M. avium complex) was evaluated and the protective effect of BCG vaccination analysed.Design: In 1986–1993, out of 190 874 non-vaccinated children, 36 were found to be infected by M. avium complex; 27 of them developed disease, i.e. mycobacteriosis other than tuberculosis (MOTT).Results: The annual risk of infection with M. avium complex was 4.8/100 000 children per year, of whom 3.6/ 100 000 developed mycobacteriosis. 24 patients suffered from swelling of cervical lymph nodes, 2 of mediastinal lymph nodes and one child had the disease localized both in cervical and mediastinal lymph nodes. The disease was verified bacteriologically in 9 children. Most of the diseased children had impaired immunity; a marked skin reactivity of M. avium complex sensitin was present in all infected children.Animal sources infected by M. avium complex were detected in 5 cases. Another 14 children also had close contact with animals but without proven M. avium complex infection.Conclusion: In non-BCG vaccinated children the incidence of lymphadenitis caused by M. avium complex was considerably higher than in vaccinated children. BCG cells possess antigenic determinants which confer protective immunity probably both against M. tuberculosis and against M. avium complex infections. It may thus be assumed that BCG vaccination protects both against pathogenic tubercle bacilli and M. avium complex. This should be taken into consideration before recommending discontinuation of mass BCG vaccination of newborns in areas with a high prevalence of M. avium complex infection.     

Polymerase chain reaction for the differentiation of Mycobacterium intracellulare and Mycobacterium avium

Polymerase chain reaction (PCR) amplification was performed using DNA purified from 15 mycobacterial type strains and from 21 specimens isolated from patients suspected to have non-tuberculous mycobacterial diseases. Using a primer set of MTB1-MTB2,11 specimens out of 21 were Mycobacterium avium and 8 were M. intracellulare, which were verified by the Gen Probe Rapid Diagnostic System for the M. avium complex (MAC). One of the remaining 2 specimens which did not hybridize with the probe for the MAC was identified as M. kansasii and the other was not specifically identified by the conventional culture method. PCR amplification, using a primer set of TB1-TB3, was also performed for the specific identification of M. tuberculosis complex.     

Clinical and pathological characteristics of mycobacterial tenosynovitis and arthritis

Purpose

To investigate the clinical characteristics and pathological features of patients with mycobacterial tenosynovitis and arthritis.

Methods

All patients with tenosynovitis and arthritis caused by Mycobacterium tuberculosis (MTB) and nontuberculous mycobacteria (NTM) who were treated at a medical center in Taiwan from 2001 to 2010 were analyzed.

Results

Thirty-two patients with mycobacterial tenosynovitis and arthritis were identified. MTB was isolated exclusively from patients with arthritis of large joints (n = 11), while NTM were isolated from patients with arthritis of large joints (n = 4) and from those with tenosynovitis (n = 17). Among patients with tenosynovitis due to NTM, the most commonly found NTM were M. marinum (n = 7), M. intracellulare (n = 5), and M. abscessus (sensu stricto) (n = 2). Six of the seven patients with tenosynovitis due to M. marinum had suffered fishing-related injuries to the hands. All four patients with NTM arthritis had recurrent septic arthritis after surgery. NTM were isolated once from the debrided tissue specimens in three of these patients; the other patient died of systemic infection caused by M. intracellulare and multiple bacterial pathogens.

Conclusion

Mycobacterial tenosynovitis should be considered in patients who present with indolent symptoms of chronic tenosynovitis. Complete clinical information, including history of trauma or joint replacement surgery and underlying systemic disease, is helpful in establishing an early diagnosis of the disease.