Publications by authors named "Michael Iseman"

The household is a potential source of opportunistic pathogens to humans, a particularly critical issue for immunodeficient individuals. An important human-microbe interface is the biofilm that develops on showerhead surfaces. Once microbe-laden biofilms become aerosolized, they can potentially be inhaled into the lungs.

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The geographic overlap between the prevalence of cigarette smoke (CS) exposure and tuberculosis (TB) in the world is striking. In recent years, relatively large number of studies has linked cigarette or biomass fuel smoke exposure and various aspects of TB. Our goals are to summarize the significance of the known published studies, graphically represent reports that quantified the association and discuss their potential limitations.

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We previously found that a subset of patients with pulmonary non-tuberculous mycobacterial (pNTM) disease were taller, leaner, and had a higher prevalence of pectus excavatum and scoliosis than uninfected controls. Additionally, whole blood of pNTM patients stimulated ex vivo with live Mycobacterium intracellulare produced significantly less interferon-gamma (IFNγ) compared to that of uninfected controls. Since IFNγ production can be suppressed by transforming growth factor-beta (TGFβ), an immunosuppressive cytokine, we measured basal and M.

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In modern times a relationship between tuberculosis (TB) and rheumatoid arthritis (RA) has been firmly recognized, and is primarily attributable to the immunosuppressive therapies used to treat RA. Whereas TB can complicate the successful management of RA, nontuberculous mycobacteria have now perhaps become as important as (if not more so than) TB in the setting of RA, and can represent an even greater challenge to the rheumatologist wishing to use immunosuppressive therapies. This article reviews our most recent understanding of the epidemiological and clinical aspects of mycobacterial disease as it relates to RA, and the existing and emerging immunosuppressive therapies used to treat this disease.

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The incidence of lung and other diseases due to nontuberculous mycobacteria (NTM) is increasing. NTM sources include potable water, especially in households where NTM populate pipes, taps, and showerheads. NTM share habitats with free-living amoebae (FLA) and can grow in FLA as parasites or as endosymbionts.

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Nontuberculous mycobacteria (NTM) are environmental microbes that cause a variety of human diseases, particularly chronic lung infections. Despite the fact that NTM are widespread in the environment, relatively few people develop NTM lung disease, suggesting intrinsic vulnerability in some individuals. This paper reviews the evidence that underlying disorders predispose to NTM lung disease, in particular primary conditions that result in bronchiectasis, chronic obstructive pulmonary disease, α-1-antitrypsin anomalies, pneumoconiosis, pulmonary alveolar proteinosis, and frank immunosuppressive states such as that associated with the use of anti-tumor necrosis factor-α biologics, posttransplantation immunosuppression, and HIV infection.

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Rationale: Among patients with nontuberculous mycobacterial lung disease is a subset of previously healthy women with a slender body morphotype, often with scoliosis and/or pectus excavatum. We hypothesize that unidentified factors predispose these individuals to pulmonary nontuberculous mycobacterial disease.

Objectives: To compare body morphotype, serum adipokine levels, and whole-blood cytokine responses of patients with pulmonary nontuberculous mycobacteria (pNTM) with contemporary control subjects who are well matched demographically.

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Background: Treatment of multidrug resistant tuberculosis (MDR-TB) is lengthy, toxic, expensive, and has generally poor outcomes. We undertook an individual patient data meta-analysis to assess the impact on outcomes of the type, number, and duration of drugs used to treat MDR-TB.

Methods And Findings: Three recent systematic reviews were used to identify studies reporting treatment outcomes of microbiologically confirmed MDR-TB.

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The purpose of this article is to update specialists in pulmonary medicine on the role of surgical resection and lung transplantation for bronchiectasis. The focus is on pre-operative workup, the technical details of surgical resection, complications, and outcomes.

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Phylogenetic analyses on the basis of multiple house-keeping genes and whole genome sequences have offered new insights in the phylogeny of the genus Mycobacterium. This genus yields obligate pathogens, the M. tuberculosis complex and M.

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Patients with rheumatologic disease are at increased risk for mycobacterial infections because of both immunocompromising therapy and preexisting lung damage from the disease itself. Tuberculosis is uncommon in the United States; however, it is relatively more prevalent in immigrants, minorities, elderly, persons with acquired immune deficiency syndrome and among healthcare workers. In the United States, the nontuberculous mycobacteria (NTM) are now more prevalent than tuberculosis.

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Background: Cigarette smoke (CS) exposure is an epidemiological risk factor for tuberculosis, although the biological basis has not been elucidated.

Methods: We exposed C57BL/6 mice to CS for 14 weeks and examined their ability to control an aerosol infection of Mycobacterium tuberculosis Erdman.

Results: CS-exposed mice had more M.

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Rationale: Long-term survivors of cystic fibrosis (CF) (age > 40 yr) are a growing population comprising both patients diagnosed with classic manifestations in childhood, and nonclassic phenotypes typically diagnosed as adults. Little is known concerning disease progression and outcomes in these cohorts.

Objectives: Examine effects of age at diagnosis and gender on disease progression, setting of care, response to treatment, and mortality in long-term survivors of CF.

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Background: Nontuberculous mycobacteria (NTM) are environmental microbes that are associated with a variety of human diseases, particularly chronic lung infections. Over the past several decades, NTM lung disease has been increasingly seen in postmenopausal women with slender body habitus.

Objective: This article reviewed the clinical and experimental evidence that supports the observation that thin older women (aged 50-80 years) are predisposed to NTM lung disease.

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Multidrug-resistant tuberculosis (TB) strains resistant to the fluoroquinolones and streptomycin but susceptible to second-line injection treatment would not be defined as extensively drug-resistant TB. In a cohort of 174 patients with multidrug-resistant TB, we demonstrated that 12 patients with multidrug-resistant TB strains resistant to the fluoroquinolones and streptomycin had significantly better initial and long-term outcomes, compared with 10 patients with extensively drug-resistant TB.

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Purpose Of Review: The spread of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant TB (XDR-TB) is a major medical and public health concern for the world. These two forms of highly drug-resistant TB threaten to make TB into an untreatable and highly fatal disease, particularly in resource-poor countries with a high prevalence of AIDS. The focus of this review is to highlight the current extent of the problem.

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