Identification and Distribution of Nontuberculous Mycobacteria from 2005 to 2011 in Cheonan, Korea

Abstract

BackgroundNontuberculous mycobacteria (NTM) are considered opportunistic pathogens, and several species of NTM are associated with human diseases that typically involve the pulmonary, skin/soft tissue, or lymphatic systems; such infection may also cause disseminated diseases. Recent studies have reported increasing rates of NTM-induced disease worldwide.MethodsRespiratory samples are being analyzed for acid-fast bacilli (AFB) culture and NTM identification at Dankook University Hospital in Cheonan, Korea, from September 2005 to September 2011. Identification is performed by using polymerase chain reaction-restriction fragment length polymorphism analysis targeting a novel region of the rpoB gene.ResultsA total of 25,133 specimens were received for AFB culture, of which 1,014 (4.0%) were NTM-positive. A total of 267 samples from 186 patients were tested for NTM identifications, and 232 samples from 157 patients were positive for NTM species. Among the patients who tested positive for NTM, 65.6% were men and the average age was 63.3 years. Mycobacterium avium complex, the most commonly detected NTM pathogen, was found in 65.9% of the 232 samples. The annual average percentage of NTM isolates from AFB culture-positive specimens was 31.3%: the highest rate was seen in 2011 (44.3%), followed by 2009 (37.4%) and 2010 (37.2%). An upward trend in NTM incidence was found during the study period.ConclusionThe prevalence of pulmonary NTM isolates continues to increase in Cheonan, suggesting that pulmonary NTM disease is becoming increasingly common.

Increasing Burden of Nontuberculous Mycobacteria in Korea

“…This is in line with previous studies from Korea (457812). M. abscessus-massiliense complex is the second most common etiologic organism in pulmonary NTM disease in Korea (12).…”

The Epidemiology and Geographic Distribution of Nontuberculous Mycobacteria Clinical Isolates from Sputum Samples in the Eastern Region of China

“…avium complex was the most common NTM and M . intracellulare accounted for 51.3% of all specimens [ 23 ]. Other research conducted in east Asia showed that M .…”

Pulmonary Infection and Colonization with Nontuberculous Mycobacteria, Taiwan, 2000–2012

“…Many studies have shown that there is great geographic diversity in the distribution of NTM species ( 1 , 2 , 4 , 5 ). However, few studies have investigated the distribution of NTM species, including colonizers and causative pathogens, with respect to patient gender and age ( 6 , 7 ). …”