• Tuberculosis and Respiratory Diseases
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• 제77권1호
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• pp.1-5
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• 2014

The recovery of nontuberculous mycobacteria (NTM) from respiratory specimens and the number of patients with NTM lung disease have been rapidly increasing in Korea. An early differential diagnosis of NTM lung disease from pulmonary tuberculosis (TB) is important, as the therapeutic regimen differs from that of pulmonary TB, and it is not necessary to track the contacts of patients with NTM lung disease. However, differentiating NTM lung disease from pulmonary TB remains difficult, because the clinical presentations of the two diseases are similar and a definite diagnosis of NTM lung disease based on sputum culture takes time. This review focuses on the changing epidemiology, clinical and radiographic manifestation, and laboratory diagnosis of pulmonary TB and NTM lung disease in Korea.

• Tuberculosis and Respiratory Diseases
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• 제74권6호
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• pp.251-255
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• 2013

Tuberculosis (TB) is one of the largest health problems in the world today. And the incidence of nontuberculous mycobacteria (NTM) lung disease appears to be increasing worldwide. Recently, an automated, nucleic acid amplification assay for the rapid detection of both Mycobacterium tuberculosis and rifampin resistance was developed (Xpert MTB/RIF). And fixed-dose combinations of anti-TB drugs and linezolid have been introduced in the treatment of TB. And new NTM species, named Mycobacterium massiliense, which is very closely related to Mycobacterium abscessus was reported. In this review, these recent advances in the diagnosis and treatment of TB and clinical characteristics of M. massiliense lung disease are discussed.

• Tuberculosis and Respiratory Diseases
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• 제79권2호
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• pp.74-84
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• 2016

Nontuberculous mycobacteria (NTM) are emerging pathogens that affect both immunocompromised and immunocompetent patients. The incidence and prevalence of NTM lung disease are increasing worldwide and rapidly becoming a major public health problem. For the diagnosis of NTM lung disease, patients suspected to have NTM lung disease are required to meet all clinical and microbiologic criteria. The development of molecular methods allows the characterization of new species and NTM identification at a subspecies level. Even after the identification of NTM species from respiratory specimens, clinicians should consider the clinical significance of such findings. Besides the limited options, treatment is lengthy and varies by species, and therefore a challenge. Treatment may be complicated by potential toxicity with discouraging outcomes. The decision to start treatment for NTM lung disease is not easy and requires careful individualized analysis of risks and benefits. Clinicians should be alert to those unique aspects of NTM lung disease concerning diagnosis with advanced molecular methods and treatment with limited options. Current recommendations and recent advances for diagnosis and treatment of NTM lung disease are summarized in this article.

• Tuberculosis and Respiratory Diseases
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• 제82권2호
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• pp.94-101
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• 2019

Nontuberculous mycobacteria (NTM) are ubiquitous organisms that are generally found not only in the natural environment but also in the human engineered environment, including water, soil, and dust. These organisms can form biofilms and can be readily aerosolized because they are hydrophobic owing to the presence of the lipid-rich outer membrane. Aerosolization and subsequent inhalation were the major route of NTM lung disease. Water distribution systems and household plumbing are ideal habit for NTM and the main transmission route from natural water to household. NTM have been isolated from drinking water, faucets, pipelines, and water tanks. Studies that used genotyping have shown that NTM isolates from patients are identical to those in the environment, that is, from shower water, showerheads, tap water, and gardening soil. Humans are likely to be exposed to NTM in their homes through simple and daily activities, such as drinking, showering, or gardening. In addition to environmental factors, host factors play an important role in the development of NTM lung disease. The incidence and prevalence of NTM lung disease are increasing worldwide, and this disease is rapidly becoming a major public health problem. NTM lung disease is associated with substantially impaired quality of life, increased morbidity and mortality, and high medical costs. A more comprehensive understanding of the infection source and epidemiology of NTM is essential for the development of new strategies that can prevent and control NTM infection.

• Tuberculosis and Respiratory Diseases
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• 제78권4호
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• pp.416-418
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• 2015

Mycobacterium shinjukuense is a novel species of nontuberculous mycobacteria (NTM) that was first reported in Japan in 2011. It is a slow-growing NTM pathogen that can cause chronic pulmonary infections. There are only a few reported cases of M. shinjukuense infections, all of which are from Japan. We reported a case of chronic lung disease caused by M. shinjukuense. The organism was identified by 16S rRNA, rpoB, and hsp65 gene sequencing. To the best of our knowledge, this was the first confirmed case of lung disease caused by M. shinjukuense outside of Japan.

• 대한임상검사과학회지
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• 제52권4호
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• pp.349-355
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• 2020

최근 호흡기 검체에서 결핵균(Mycobacterium tuberculosis complex, MTBC) 검출은 감소하고 비결핵 항산균(nontuberculous mycobacteria, NTM)은 증가하고 있다. 본 연구는 2010년부터 2019년까지 광주 2차 병원에 의뢰된 호흡기검체 132,359예를 대상으로 NTM 검출 증가 대비 NTM 폐질환 환자의 증가와 연령 및 성별 분포를 조사하였다. 그리고 NTM양성환자의 폐결핵 감염 여부를 확인하고자 하였다. 항산균배양 양성률은 2010년 21.9% (1,624/7,403), 2019년 17.4% (1,937/11,161)였다. NTM 분리 비율은 2010년 38.0% (617/1,624)에서 2019년에 72.4% (1,403/1,937)로 증가하였다. NTM 양성환자의 NTM 폐질환 진단률은 평균 27.1%였다. 이 중 현재 폐결핵에 감염된 사례는 2010년 44.4%에서 2019년 23.5%로 감소하고 과거 진단 또는 치료 사례도 15.6%에서 10.6%로 감소하였다. 전체 NTM 폐질환 중 69.0%가 60대 이상이었으며 남자보다 여자 환자가 더 많았다. 향후 고령화와 결핵 관리 정책에 따라 NTM 검출은 증가하는 반면 MTBC는 감소할 것으로 예상되며, 실험실에서는 이 현상에 세심한 주의를 기울이고 지속적으로 검사 결과를 감시해야 할 것이다.

• Tuberculosis and Respiratory Diseases
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• 제72권2호
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• pp.173-176
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• 2012

We report a rare case of lung disease caused by Mycobacterium terrae in a previously healthy woman. A 45-year-old woman was referred to our hospital due to a chronic cough with sputum. A computed tomography scan of the chest revealed bronchiolitis in conjuction with bronchiectasis in both lungs. Nontuberculous mycobacteria were identified and isolated from the bronchoalveolar lavage fluid collected from each lung. All isolates were identified as M. terrae by various molecular methods that characterized the rpoB and hsp65 gene sequences. Antibiotic therapy using clarithromycin, rifampin, and ethambutol improved the patient's condition and successfully resulted in sputum conversion.

• Tuberculosis and Respiratory Diseases
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• 제74권4호
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• pp.187-190
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• 2013

We report a rare case of lung disease caused by Mycobacterium lentiflavum in a previously healthy woman. A 54-year-old woman was referred to our hospital due to chronic cough and sputum. A computed tomography scan of the chest revealed bilateral bronchiectasis with bronchiolitis in the right middle lobe and the lingular division of the left upper lobe. Nontuberculous mycobacteria were isolated twice from three expectorated sputum specimens. All isolates were identified as M. lentiflavum by multilocus sequence analysis based on rpoB, hsp65, and 16S rRNA fragments. To the best of our knowledge, this is the first documented case of M. lentiflavum lung disease in an immunocompetent adult in Korea.

• Tuberculosis and Respiratory Diseases
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• 제80권2호
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• pp.153-158
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• 2017

Background: Recently, increased levels of high-mobility group box 1 protein (HMGB1) have been identified in various inflammatory conditions and infections. However, no studies have evaluated the HMGB1 level in nontuberculous mycobacterial (NTM) lung disease, and compared it to mycobacterial lung disease. Methods: A total of 60 patients newly diagnosed with NTM lung disease, 44 culture-positive pulmonary tuberculosis (TB) patients, and 34 healthy controls, were included in this study. The serum HMGB1 concentrations were quantified using HMGB1 enzyme-linked immunosorbent assay kits. Results: Serum HMGB1 level in patients with pulmonary TB or NTM lung disease, was significantly lower than that of the healthy controls. In addition, the serum HMGB1 level in TB patients was significantly lower than patients with NTM lung disease. However, the levels in NTM patient subgroups did not differ according to the causative species, disease progression, and disease phenotype. Conclusion: Although low levels of serum HMGB1 has the potential to be a marker of mycobacterial lung disease, these levels were unable to differentiate disease progression and disease phenotype in NTM lung diseases.

• Tuberculosis and Respiratory Diseases
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• 제72권3호
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• pp.275-283
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• 2012

Background: Healthy individuals who develop nontuberculous mycobacteria (NTM) lung disease are likely to have specific susceptibility factors which can lead to a NTM infection. The aim of the present study was to investigate the mechanism underlying innate immune responses, including the role of mitogen-activated protein kinase (MAPK), in Mycobacterium abscessus lung disease. Methods: Extracellular signal-regulated kinase (ERK1/2) and p38 MAPK expression in monocytes from peripheral blood mononuclear cells were measured by Western blot analysis after stimulation by Mycobacterium avium in five patients with M. abscessus lung disease and seven healthy controls. A M. avium-induced cytokine assay was performed after inhibition of ERK1/2 and p38 MAPK pathways. Results: Mycobacterium avium induced p38 and ERK1/2 expression in monocytes from healthy controls and subsequently upregulated tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, and IL-10 production. In monocytes from patients with M. abscessus lung disease, however, induction of p38 and ERK1/2 expression, and the production of TNF-${\alpha}$, IL-6, and IL-10 were significantly lower. Conclusion: Decreased activity of MAPK and cytokine secretion in monocytes from patients with M. abscessus lung disease may provide an explanation regarding host susceptibility to these uncommon infections.