Radiologic types of Mycobacterium xenopi pulmonary disease: different patients with similar short-term outcomes.

Mycobacterium xenopi pulmonary disease (Mxe-PD) is common among nontuberculous mycobacterial infections in Europe and Canada. Associations between radiological pattern and clinical features and outcomes are inadequately studied in Mxe-PD. We sought to investigate clinical characteristics and outcomes according to the dominant radiological pattern among patients with Mxe-PD. We retrospectively studied patients with Mxe-PD seen in our clinic, categorizing their predominant CT pattern as nodular bronchiectasis, fibrocavitary, or unclassifiable, and compared clinical characteristics, treatment, and outcomes between radiologic groups. Of 94 patients with Mxe-PD, CT patterns comprised nodular bronchiectasis (40/94, 42.6%), fibrocavitary (37/94, 39.4%), and unclassifiable (17/94, 18.1%). Compared with fibrocavitation, patients with nodular bronchiectasis were female dominant, less often had COPD, less often had AFB smear-positive sputum, and more frequently had co-isolation of Pseudomonas. Patients with nodular bronchiectasis were less often treated (65% versus 91.9%) and when treated, they received fewer anti-mycobacterial drugs (on average 3 versus 4). Outcomes did not differ significantly by radiological pattern. Nodular bronchiectasis was common among Mxe-PD patients in our clinic. Compared with fibrocavitary disease, patients with nodular bronchiectasis had features suggestive of milder disease and were less often treated. Among treated patients, outcomes did not differ by radiologic pattern.

Mycobacterium xenopi y carcinoma pulmonar de células escamosas / Mycobacterium xenopi and squamous cell carcinoma of the lung

No disponible

Factors which influence treatment initiation for pulmonary non-tuberculous mycobacterium infection in HIV negative patients; a multicentre observational study.

BACKGROUND: Clinical, radiological and microbiological criteria inform diagnosis of pulmonary Non-Tuberculous Mycobacteria (NTM) disease and treatment decisions. This multicentre, review aims to characterise NTM disease meeting ATS/IDSA criteria and define factors associated with initiation of treatment. METHODS: Sputum samples growing NTM from 5 London hospitals between 2010 and 2014 were identified. Data for HIV-negative individuals meeting ATS/IDSA guidelines for pulmonary NTM disease were extracted. Associations between clinical variables and treatment decision were investigated using Chi-squared, Fishers-exact or Mann Whitney tests. Factors associated with treatment in univariate analysis (p < 0.150) were included in a multivariate logistic regression model. RESULTS: NTM were identified from 817 individuals' sputum samples. 108 met ATS/IDSA criteria. 42/108 (39%) were initiated on treatment. Median age was 68 (56-78) in the cohort. On multivariate analysis, factors significantly associated with treatment of pulmonary NTM infection were: Cavitation on HRCT (OR: 6.49; 95% CI: 2.36-17.81), presenting with night sweats (OR 4.18; 95% CI: 1.08-16.13), and presenting with weight loss (OR 3.02; 95% CI: 1.15-7.93). Of those treated, 18(43%) have completed treatment, 9(21%) remain on treatment, 10(24%) stopped due to side effects, 5(12%) died during treatment. Mortality was 31% (n = 13) in treated versus 21% (n = 14) in the non-treated cohort. Subgroup analysis of individual NTM species did not observe any differences in treatment initiation or outcomes between groups. DISCUSSION: Decision to treat pulmonary NTM infection requires clinical judgement when interpreting clinical guidelines. Factors independently associated with decision to treat in this HIV-negative cohort include cavitation on HRCT and presenting with night sweats or weight loss.

Miliary pulmonary nodules due to Mycobacterium xenopi in a steroid-induced immunocompromised patient successfully treated with chemotherapy: a case report.

BACKGROUND: Mycobacterium xenopi-infected patients have a high prevalence of pulmonary cavities and nodules. However, the clinical course for patients with miliary nodules due to M. xenopi has not yet been reported. CASE PRESENTATION: We encountered a case of miliary nodules with gradually worsening coughing and sputum production in a 44-year-old male who had renal dysfunction due to glomerulosclerosis with a decade-long history of steroid therapy. Although we started anti-tuberculosis treatment on clinical suspicion of miliary tuberculosis, cultures of sputum and bronchial lavage were both positive for M. xenopi. The patient was successfully treated with rifampin, ethambutol and clarithromycin, without fibrosis. It was unclear whether the miliary pattern was induced by hematogenous or endobronchial spread of the M. xenopi infection. CONCLUSION: Even when clinical and radiological disease manifestations are similar to those of miliary tuberculosis, M. xenopi infection should be considered in the differential diagnosis of miliary nodules.

A Case of Lung Cancer Originating from Cavitary Mycobacterium xenopi Infection.

Coexistence of Mycobacterium xenopi with lung cancer has been reported. However, lung cancer originating within a pre-existing cavity caused by M. xenopi has not. A 55-y-old woman with a history of smoking presented with complaints of chronic dry cough, night sweats, and weight loss for several months. Computed tomography (CT) scanning revealed a 3.5-cm irregular thick-walled cavity in the right lung apex. Cultures obtained from a CT-guided biopsy grew M. xenopi. The patient received standard treatment, and her clinical symptoms improved, and the radiographic lesion stabilized. However, 2 y later, a repeat chest x-ray showed the original right upper lobe cavity with an interval development of a mass adjoining the cavity. A CT-guided needle biopsy of the new mass demonstrated squamous cell carcinoma. Whenever there is a change in the radiological appearance of a cavity, a repeat biopsy should be performed to exclude lung cancer.

Non-tuberculous mycobacterial infections at San Francisco General Hospital.

BACKGROUND AND AIMS: The epidemiology of non-tuberculous mycobacteria (NTM) infection is not well defined. We evaluated the trends in incidence of NTM infections at San Francisco General Hospital (SFGH), a large metropolitan county hospital. METHODS: We performed a retrospective review of microbiologic and clinical records of all patients with a positive NTM culture reported from 1993 to 2001. NTM infection was defined by the isolation of >1 NTM from any clinical specimen. Patients were stratified by human immunodeficiency virus (HIV) status. Univariate and multivariate logistic regression were used to identify factors that were independently associated with NTM infection. Trends over time were assessed using Poisson test for trend. RESULTS: During the study period, 25 736 samples from 7395 patients were cultured for mycobacteria. Of these samples, 2853 (11.1%) from 1345 patients (18.2%) were culture positive for NTM. Patient characteristics associated with infection included younger age (P < 0.001), male gender (P < 0.001), White ethnicity compared with Asian and Hispanic (P < 0.001 and P = 0.01, respectively), and HIV positivity (P < 0.001). Overall, NTM infection at SFGH decreased significantly from 319 cases in 1993 to 59 in 2001 (P < 0.001). Mycobacterium avium was predominant in both HIV-positive and HIV-negative populations (74.5% and 44.6% of isolates, respectively), and Mycobacterium kansasii was the second most common NTM species isolated. The proportion of other NTM species isolated in these groups differed. CONCLUSION: In contrast to other published studies, time-series analyses show that NTM isolation rates decreased during the study period at SFGH, where NTM was most strongly associated with HIV infection.

Isolation of non-tuberculous mycobacteria among patients with pulmonary tuberculosis in Ontario, Canada.

SETTING AND OBJECTIVE: There are limited data regarding the frequency and significance of co-isolating pulmonary non-tuberculous mycobacteria (NTM) in patients with pulmonary tuberculosis (PTB). DESIGN: We identified all patients with culture-proven PTB in Ontario, Canada, in 2004, identified those with NTM 'co-isolation' (≤6 months following initial TB isolate) and determined subsequent NTM isolation over 5 years. RESULTS: In 2004, 369 people in Ontario had culture-proven PTB (average age 46 years, SD 21, 41% female). NTM co-isolation occurred in 11% (40/369), including Mycobacterium avium complex 22/40 (55%), M. xenopi 7/40 (18%), M. gordonae 6/40 (15%) and others 5/40 (13%). Patients with NTM co-isolation were older (55 vs. 45 years, P = 0.004), but had similar sex ratios (females 43% vs. 40%, P = 0.87). Among patients with co-isolation, 23% (9/40) went on to have ≥2 NTM cultures (excluding initial culture), compared with 3% (10/329) in the PTB group (including initial culture, P = 0.0001). In the co-isolation group, the median (quartiles) number of samples collected for mycobacterial study was 6 (4-8) compared to 2 (1-4) in the PTB group (P < 0.0001). CONCLUSIONS: The high frequency of subsequent NTM isolation among patients with NTM co-isolation during PTB may warrant follow-up for potential NTM disease.

Complete genome sequence of Mycobacterium xenopi type strain RIVM700367.

Mycobacterium xenopi is a slow-growing, thermophilic, water-related Mycobacterium species. Like other nontuberculous mycobacteria, M. xenopi more commonly infects humans with altered immune function, such as chronic obstructive pulmonary disease patients. It is considered clinically relevant in a significant proportion of the patients from whom it is isolated. We report here the whole genome sequence of M. xenopi type strain RIVM700367.

[Pulmonary aspergillosis complicating atypical mycobacterial infection in two patients suffering from chronic obstructive pulmonary disease]. / Aspergillose pulmonaire compliquant une infection à mycobactérie atypique chez deux patients atteints de bronchopneumopathie chronique obstructive.

INTRODUCTION: Atypical mycobacteria and Aspergillus are opportunistic organisms responsible for severe pulmonary diseases whose development is encouraged by the presence of chronic obstructive pulmonary disease (COPD) and related immunosuppression. CASE REPORTS: We report the cases of two patients, both alcoholics with emphysematous COPD, who developed chronic pulmonary aspergillosis following atypical mycobacterial infection. Patient 1 developed chronic necrotising aspergillosis several months after the diagnosis of infection with Mycobacterium avium. Patient 2 developed an aspergilloma several weeks after the diagnosis of infection with Mycobacterium xenopi. The association of these two pathologies presents diagnostic and therapeutic problems that are discussed. CONCLUSION: The development of Aspergillus pulmonary disease may complicate atypical mycobacterial infections and explain a poor response to treatment. Our two case reports suggest that a systematic search should be made for pulmonary aspergillosis during the follow-up of patients with atypical mycobacterial infection.

[Nontuberculous mycobacteria: M. marinum, M. ulcerans, M. xenopi - brief characteristics of the bacteria and diseases caused by them]. / Pratki niegruzlicze: M. marinum, M. ulcerans, M. xenopi ­ krótka charakterystyka drobnoustrojów i zmian klinicznych przez nie wywolywanych.

Mycobacterium is a variable group of acid-fast bacillus which contains pathogenic bacteria causing tuberculosis (MTC - Mycobacterium tuberculosis complex) and leprosy (M. leprae) as well as numerous nontuberculous mycobacteria (NTM) causing diseases mostly in people with immunodeficiency, although some NTM strains are capable of causing illnesses in non-immunocompromised patients. This group includes for example Mycobacterium marinum, Mycobacterium ulcerans and Mycobacterium xenopi. These microorganisms are environmental mycobacteria, present in developing countries of Africa, but they may also be transferred to other continents. The most common symptoms of diseases caused by these species are skin lesions (hyperpigmentation, tumors, ulcers) and arthritis. Because of the rarity of their occurrence, these mycobacteria are relatively poorly known. Effective ways of treating the diseases caused by these bacilli are still under study.

Mycobacterium heckeshornense lung infection that was diagnosed as Mycobacterium xenopi disease by DNA-DNA hybridization (DDH).

The DNA sequencing analyses of the 16S rRNA gene, rpoB and hsp65 were conducted to characterize six strains that had been identified as Mycobacterium xenopi by DNA-DNA hybridization (DDH) for past ten years in our hospital. The results revealed Mycobacterium heckeshornense infection in one of the six cases. A 47-year-old man, who had been treated for pneumonia, had pulmonary nontuberculous mycobacterial disease. The sputa from the patient were culture positive for mycobacterium in three times. And it was diagnosed as M. xenopiby DDH method. Chest X-ray showed fibrocavitary lesion in right upper lobe was successfully treated with clarithromycin for four weeks.

[Significance of local and general risk factors for the pathogenesis of pulmonary, non-tuberculous mycobacteriosis in non-AIDS patients]. / Bedeutung der lokalen und allgemeinen Risikofaktoren für die Pathogenese der pulmonalen nicht-tuberkulösen Mykobakteriosen bei Nicht-AIDS-Patienten.

BACKGROUND: Pre-existing underlying bronchopulmonary diseases and relative impairments of the immune system are risk factors that predispose to the development of pulmonary infections with non-tuberculous mycobacteria (NTM), even if the impairment is not severe. METHODS: In a prospective study n = 111 patient diagnoses between 1992 and 2004 were included. The criterion for inclusion was laboratory evidence of non-tuberculous mycobacteria. The local risk factors and general risks were recorded for each case and the total number of risks for each patient was counted. Risk profiles were drawn up and risk scores calculated for different groups. RESULTS: N = 66 patients met the ATS criteria for NTM disease. The disease rates for the most frequent species varied widely ( M. AVIUM complex 57 %, M. KANSASII 100 %, M. XENOPI 73 %). Older women (> 65 years) with M. AVIUM complex were rarely ill. The risk factors were almost equally frequent for patients meeting criteria for disease status and those who did not and patients under 65 years of age had fewer local risk factors than older patients. Patients with M. GORDONAE showed fewer local risk factors than patients with M. AVIUM complex or M. XENOPI. CONCLUSIONS: Even local risk factors predispose towards infections with mycobacteria and do not only lead to disease after infection. Bullous changes of the lungs, cavities and bronchiectasis are local risk factors, but can also develop as sequelae of mycobacteriosis. There is sufficient evidence to support the continued use of the concept of colonisation alongside those of infection with and infection without disease status. In our region, a thorough evaluation is needed to establish whether older women with M. AVIUM complex actually have mycobacteriosis.

Pulmonary Mycobacterium xenopi infection in non-HIV-infected patients: a systematic review.

SETTING: The incidence of Mycobacterium xenopi infections is increasing worldwide. The characteristics and optimal management of patients with pulmonary M. xenopi infections have not been well established. METHODS: Systematic review of English- and French-language studies reporting at least two cases of microbiologically confirmed M. xenopi lung infection. Studies were independently reviewed by two reviewers. We described the risk factors and clinical presentation of advanced infection, and examined the impact on clinical success and mortality of including individual antimycobacterial drugs in the treatment regimen. RESULTS: A total of 48 studies reporting on 1255 subjects were included. The majority were retrospective case series. There was marked heterogeneity among the studies. Patients were generally middle-aged men with a history of obstructive lung disease or prior tuberculosis, presenting with an upper lobe cavitary infection. There was no clear association between administration of particular drugs and clinical success or mortality. CONCLUSION: We could not demonstrate any advantage of specific drugs in the treatment of pulmonary M.xenopi infection. Observations from the pooled data are likely subject to significant confounding and selection biases. The inability to make firm conclusions on the optimal management of this increasingly common infection strongly underscores the need for further research.

Tracheal granuloma because of infection with a novel mycobacterial species in an old FIV-positive cat.

A 15-year-old domestic shorthair feline immunodeficiency virus-positive cat was presented with a five day history of productive cough and acute respiratory distress. Physical examination revealed inspiratory dyspnoea and diffuse gingivostomatitis. Radiographs showed an intratracheal mass located at the level of the sixth and the seventh cervical vertebrae. Bronchoscopy revealed a unique intratracheal mass occluding about 85 per cent of the tracheal lumen. The tracheal mass was removed bronchoscopically. A diagnosis of pyogranulomatous inflammation referable to a mycobacterial infection was made based on cytological and histopathological findings. 16S rRNA polymerase chain reaction testing and sequence analysis identified a novel mycobacterial species, likely a slow grower, with 95 per cent identity with Mycobacterium xenopi. To our knowledge, this is the first description of a tracheal mycobacterial granuloma in a cat, and the first time, a mycobacterium with this sequence has been identified.

Non-tuberculous mycobacteria in the sputum of HIV-infected patients: infection or colonization?

It can be difficult to establish the clinical significance of the isolation of non-tuberculous mycobacteria (NTM) from the sputum of HIV-infected patients. In this observational study, we have investigated factors associated with having NTM infection. During the period of the study, 10 patients had NTM infection and 14 had NTM colonization. Factors associated with having NTM infections were: CD4 lymphocyte count <50 cells/mL (odds ratio [OR] 10; 95% confidence interval [CI] 1.4-69.3), haemoglobin <11 g/dL (OR 7.2; 95% CI 1.08-47.9), weight loss (OR 9; 95% CI 1.3-63.9), duration of symptoms for more than a month (OR 54; 95% CI 4.2-692.5), the presence of acid fast bacilli (AFB) in sputum (OR 30.3; 95% CI 2.6-348.9) and repeated positive NTM cultures in other sputum samples (OR 4.3; 95% CI 1.6-11.7). In conclusion, we must suspect NTM infection in patients with long-standing symptoms, anaemia, low CD4 lymphocyte count, several positive sputum cultures and when AFB are seen.

Mycobacterium xenopi pulmonary disease - epidemiology and clinical features in non-immunocompromised patients.

OBJECTIVES: The genus Mycobacterium has more than 120 well-characterized species. Although the incidence of tuberculosis has decreased over the studied period, other, non-tuberculous mycobacteria (NTM) are isolated more often. Since, Mycobacterium xenopi is the most frequent NTM isolate in Croatia we studied its epidemiology and clinical relevance. METHODS: We performed a retrospective study over a 25-year period determining epidemiology, radiological findings and clinical importance of M. xenopi infection, obtaining data from archives in health care institutions from all over the country. RESULTS: We detected 40 patients with a positive isolate of M. xenopi. Twenty-four patients met American Thoracic Society criteria for pulmonary disease. Eighteen (90%) of treated patients were male, on average 61.7 years old. Nineteen (95%) patients lived in towns. Most of them had comorbid disease, 18 (90%), with chronic obstructive pulmonary disease (COPD) being the most frequent, found in 11 (55%) patients. All patients were immunocompetent. We found COPD as the most frequent comorbid disease in the group of patients with worse treatment response (n=8; 80%), while in patients with good treatment response COPD was less frequent (n=3; 30%). Differences in the proportions of patients with COPD were significant (p=0.037). CONCLUSION: In patients with M. xenopi pulmonary infection, COPD is a predisposing condition, and as a comorbid disease, is an important prognostic factor for treatment response.

Unreliable detection of Mycobacterium xenopi by the nonradiometric Bactec MGIT 960 culture system.

From June 2006 to December 2007, 3,648 clinical specimens consecutively received for mycobacterial culture were investigated. Each processed sample was inoculated into Bactec MGIT 960 liquid medium and a Löwenstein-Jensen slant. Tubes that were flagged as positive by the instrument as well as those determined to be negative after 42 days of incubation were removed, visually inspected for growth, and checked for the presence of acid-fast bacilli. Three hundred sixty-nine mycobacterial strains were recovered; of the 44 Mycobacterium xenopi isolates recovered by MGIT medium, only 13 were detected by the instrument (P<0.0001). Most tubes yielding M. xenopi exhibited a peculiar pattern of growth characterized by a scant number of round, yellow-pigmented granules instead of the fine, evenly dispersed clumps usually observed for mycobacteria. It is suggested to check all individual tubes discarded by the MGIT 960 system at the end of the incubation period to prevent a significant amount of previously undetected growth from being missed.