• Tuberculosis and Respiratory Diseases
• /
• v.86 no.1
• /
• pp.47-56
• /
• 2023

Background: There is a global increase in isolation of nontuberculous mycobacteria (NTM). The aim of the study was to analyze longitudinal trends of NTM identification and pattern of antimicrobial susceptibility testing. Methods: NTM recovery rates, distribution of NTM species identification, and antimicrobial susceptibility pattern of NTM at Pusan National University Yangsan Hospital between January 2016 and December 2020 were retrospectively analyzed. Results: A total of 52,456 specimens from 21,264 patients were submitted for mycobacterial culture, of which 2,521 from 1,410 patients were NTM positive over five years (January 2016 to December 2020). NTM isolation showed an increasing trend from 2016 to 2020 (p<0.001, test for trend) mainly caused by Mycobacterium avium complex. The vast majority of M. avium complex were susceptible to key agents clarithromycin and amikacin. For Mycobacterium kansasii, resistance to rifampin and clarithromycin is rare. Amikacin was the most effective drug against Mycobacterium abscessus subspecies abscessus and Mycobacterium subspecies massiliense. Most of M. subspecies massiliense were susceptible to clarithromycin, while the majority of M. abscessus subspecies abscessus were resistant to clarithromycin (p<0.001). Conclusion: There was an increasing trend of NTM isolation in our hospital. Resistance to key drugs was uncommon for most NTM species except for M. abscessus subspecies abscessus against clarithromycin.

• Tuberculosis and Respiratory Diseases
• /
• v.74 no.6
• /
• pp.251-255
• /
• 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
• /
• v.72 no.2
• /
• pp.173-176
• /
• 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.

• Korean Journal of Veterinary Research
• /
• v.33 no.1
• /
• pp.119-123
• /
• 1993

The present study was intended to use the avidin-biotin-peroxidase-antiperoxidase complex (ABPAP) method for the identification of Mycobacterium bovis in the tissue sections of infected cattle. Antibodies and linksera for ABPAP procedure used in incubated order were rabbit anti-Mycobacterium polyvalent antibodies, goat anti-rabbit IgG, rabbit peroxidase-antiperoxidase complex, biotinyl-horse anti-rabbit IgG, and avidin-biotin-peroxidase complex. Where the bacterial antigen was localized by ABPAP, a dark brown deposit occurred in the cytoplasms of macrophages and Langerhans' giant cells of the granulomatous lesions. The method approved to be highly specific for the identification of the bacteria and allowed a precise localization of the bacterial antigen in infected cells.

• Journal of Microbiology
• /
• v.42 no.3
• /
• pp.239-242
• /
• 2004

This study examined the detection rate of the hepatitis B virus (HBV) and Mycobacterium tuberculosis (Mtb) in serum and saliva samples, respectively, from 120 dental patients who were unaware if they have or had either hepatitis or tuberculosis. The frequencies of HBsAg and anti-HBs were determined using an immunochromatic assay. Mtb positivity was determined by the PCR method. Of the 120 patients, 7 (5.8％) were HBV positive and 30 (25.0％) were Mtb positive. This highlights the fact that dental health care workers (DHCWs) can be exposed to the risk of infection from blood- or saliva-borne pathogens as a consequence of their work. Therefore, it is very important to prevent cross infection between patients and dental personnel. Accordingly, laboratory tests prior to surgical treatment are needed to determine the infectious state of dental patients in order to prevent the transmission of infectious diseases in dental clinics.

• Korean Journal of Veterinary Service
• /
• v.25 no.2
• /
• pp.135-140
• /
• 2002

The purpose of this study was to detect Mycobacterium bovis in cattle(serum, milk, lung, lymph node) by PCR. Nineteen samples from 7 skin test-positive cattle were analyzed. The amplified band of IS6110 by PCR was detected from 2 samples in lung and Iymph node. But the sensitivities of the present methods for detecting M bovis in milk and serum are deficient. Because the PCR sensitivity has been shown to be hindered by the method used to isolate the nucleic acid target. PCR-based methods have the potential to be faster, more accurate, and the most efficient means of detecting M bovis. The detection of M bovis by PCR will contribute to the more efficient detection and control of tuberculosis.

• YAKHAK HOEJI
• /
• v.24 no.1
• /
• pp.1-10
• /
• 1980

Viomycin inhibited polypeptide biosynthesis, initiation complex formation and translocation of peptidyl-tRNA on ribosomes derived from a sensitive strain of Mycobacterium smegmatis (R-15), but not significantly on ribosomes from viomycin-resistant mutants(R-31 and R-43). The inhibition of translocation was stronger than that of initiation complex formation in the sensitive strain. The binding of [$^{14}C$] tuberactinomycin O, a viomycin analog, to ribosomal particles was studied by Millipore filter method. The sensitive ribosome exhibited higher affinity for the antibiotic than the resistant ribosomes. The resistance was localized on the large ribosomal subunit in a mutant(R-31), and on the small subunit in another mutant(R-43). The binding of the drug to the sensitive ribosomal subunit was markedly reduced by combination with the resistant pair subunit, and the entire ribosome became resistant to the antibiotic.

• Tuberculosis and Respiratory Diseases
• /
• v.78 no.3
• /
• pp.293-296
• /
• 2015

Mycobacterium malmoense is a very rare cause of lung disease in South Korea. We reported the first case of lung disease caused by M. malmoense in an immunocompetent patient. The patient was successfully treated with a 14-month course of antibiotics.

• Journal of Microbiology and Biotechnology
• /
• v.13 no.2
• /
• pp.309-312
• /
• 2003

A bacterial strain NB01, isolated from wastewater, was found to utilize nitrobenzene (NB) as the sole source of nitrogen, carbon, and energy. The strain was classified as a member of a high G+C Gram-positive group and identified as Mycobacterium chelonae based on an analysis of its 16S rRNA gene sequence. The strain grew on NB with a concomitant release of about 63% of the total available nitrogen as ammonia, suggesting a reductive degradation mechanism. The optimal pH and temperature for degradation were PH 7.0-8.0 and $30^{\circ}C$, respectively. The cell growth was retarded at NB concentrations above 1.8 mM. The degradation of NB followed Michaelis-Menten kinetics within the tolerance range, and the $K_m$ and maximum specific removal rate for NB were 0.33 mM and $11.04\;h^{-1}$, respectively.

• YAKHAK HOEJI
• /
• v.41 no.5
• /
• pp.638-646
• /
• 1997

The steroid 9${alpha}$-hydroxylase activity has been detected in cytosol fraction, $100,00{\times}g$ supernatant of cell free extract of Mycobacterium fortuitum. The activity was not linear with protein concentration in the assay suggesting 9${alpha}$-hydroxylase is a multicomponent enzyme. The 9${alpha}$-hydroxylase system was partially purified through fractional saturation of ammonium sulfate, strong anion exchange (Mono Q) column chromatography, gel filtration (Superose 12) column chromatography, and testosterone affinity gel chromatography. Ammonium sulfate 50~60% saturated fraction of the cytosol gave 9${alpha}$-hydroxylase activity. For further purification, the half-saturated ammonium sulfate fraction was applied to Mono Q, Superose 12, or affinity gel column. The purification factors of 9${alpha}$-hydroxylase containing fraction after Mono Q, Superose 12, and affinity gel chromatography was 13, 11, and 17 respectively.