Characteristics of clinical isolates of nontuberculous mycobacteria in Java-Indonesia: A multicenter study

Abstract

Background Nontuberculous mycobacterial (NTM) lung infections are a major public health concern. Diagnosis of NTM-pulmonary disease (NTM-PD) is difficult because its clinical, microbiological, and radiological features resemble to those of pulmonary tuberculosis (TB), leading to misdiagnosis. Identification at the species level is essential for diagnosis and determination of therapy, which is currently not performed routinely in Indonesian laboratories. Methodology and principal findings From January 2020 to May 2021, 94 NTM isolates were collected from three TB referral centers in Java Province. Species were identified using matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). Tests were performed to determine antibiotic susceptibility, biofilm formation ability, sliding motility characteristics, and the ability to adhere to and invade pneumocytes. After identifying the species of all the isolates, we found nine groups of NTMs: M. fortuitum group 51% (48/94), M. abscessus 38.3% (36/94), M. intracellulare 3.1% (3/94), M. neoaurum 2.1% (2/94), M. chelonae 1.1% (1/94), M. gordonae 1.1% (1/94), M. szulgai 1.1% (1/94), M. mucogenicum 1.1% (1/94), and M. arupense 1.1% (1/94). Amikacin was the most effective antibiotic against M. fortuitum group and M. abscessus. The M. fortuitum group was significantly better at forming biofilms than M. abscessus, but both had the same sliding motility capability. The ability of the M. fortuitum group to adhere to and invade pneumocytes was better than that of M. abscessus, with the number isolates of the M. fortuitum group capable of superior adhesion and invasion to that of M. abscessus. Conclusions/Significance This study shows that M. fortuitum group and M. abscessus were the most common NTM found in Java, Indonesia. The M. fortuitum group and M. abscessus were the most susceptible to amikacin; therefore, this was the empirical treatment of choice. The ability to form biofilms is directly proportional to the ability to adhere to and invade pneumocytes but not to the susceptibility profile or sliding motility characteristics.

Comparative Proteomic Analysis of Exosomes Derived from Patients Infected with Non-Tuberculous Mycobacterium and Mycobacterium tuberculosis

“…Since the clinical characteristics of SGM pulmonary infection resemble MTB [ 15 ], it was necessary to explore more sensitive and specific clinical biomarkers screened from plasma omics. Between the MAC group and MTB group, a total of 31 differentially expressed exosomal proteins were identified, including 21 up-regulated and 10 down-regulated proteins ( Figure 6 A–C).…”

A laboratory perspective on Mycobacterium abscessus biofilm culture, characterization and drug activity testing

“…Different M. abscessus strains are used in biofilm research. This is important as differences in biofilm formation capability and robustness have been described among different isolates ( Martín-de-Hijas et al, 2009 ; Saptawati et al, 2022 ). Yet, the factors contributing to this (sub) strain variability and the extent to which this variability affects biofilm formation and behavior remain underexplored.…”

“…Electron microscopy is used to analyse the structure of the biofilm, the abundance of outer matrix, bacterial organization, mycobacterial density and the activity of various mycobacterial drugs or conditions with a higher spatial resolution than CLSM. In this manner, the microstructure of biofilms can be identified ( Dokic et al, 2021 ; Li et al, 2022 ; Saptawati et al, 2022 ; Yue et al, 2022 ; He et al, 2023 ). Finally, micro–CT X-ray has been used to visualize the three-dimensional structures of M. abscessus biofilms ( Cohen-Cymberknoh et al, 2022 ).…”