[Evaluation of Antimicrobial Susceptibilities of Rapidly Growing Mycobacteria]. / Hizli Üreyen Mikobakterilerin Antimikrobiyal Ilaçlara Duyarliliklarinin Belirlenmesi.

Infections related to the rapidly growing mycobacteria (RGM), which are common in the environment, have clinical significance as they can affect both immunocompromised and immunocompetent patients. Treatment of RGM related infections is difficult, because they are resistant to many of the first-line tuberculosis agents, require a long-term multiple drug regimen, which is costly, and is associated with drugrelated toxicities. The aim of this study was to investigate the in vitro antimicrobial susceptibility profiles of RGM isolated in Dokuz Eylül University Hospital and also to reveal epidemiological data. A total of 58 isolates [(Mycobacterium fortuitum (n= 35), Mycobacterium abscessus (n= 19) and Mycobacterium chelonae (n= 4)], which were isolated in Dokuz Eylül University Hospital between 2013 and 2018, were subjected to in vitro testing for nine antimicrobial agents (amikacin, cefoxitin, ciprofloxacin, clarithromycin, doxycycline, imipenem, linezolid, moxifloxacin and tobramycin) with the broth microdilution method recommended by the Clinical and Laboratory Standards Institute (CLSI). For M.abscessus; 73.68% of the isolates were found susceptible to amikacin; 73.68% of isolates were susceptible to clarithromycin at early reading and only 21.05% of them remained susceptible at late reading time. No resistance to imipenem were observed. M.abscessus isolates were highly resistant to tobramycin, doxycycline and fluoroquinolones. Antibiotic susceptibility testing of M.chelonae isolates demonstrated 100% susceptibility for amikacin, clarithromycin and tobramycin. No resistance to linezolid, imipenem and moxifloxacin were observed. None of the isolates were susceptible to cefoxitin. Ciprofloxacin and doxycycline also showed poor in vitro activity against M.chelonae isolates. For M.fortuitum clarithromycin susceptibility decreased from 32.35% to 2.94% after an additional incubation until 14 days. All tested isolates of the M.fortuitum were susceptible to amikacin, ciprofloxacin and moxifloxacin. None of the M.fortuitum isolates exhibited resistance to cefoxitin and imipenem. Most of the M.fortuitum isolates were resistant to tobramycin and doxycycline. When the results were evaluated together, RGM isolates in this study were highly susceptible to amikacin; and were highly resistant to doxycycline. In conclusion, this study supported that the status of antimicrobial susceptibilities were different between species and also showed the importance for hospitals to know susceptibility patterns of isolates in their region. It should be noted that accurate species determination is critical for treatment as well as susceptibility status of rapidly growing mycobacteria to the antimicrobials in use.

Comparison of polymerase chain reaction-restriction enzyme analysis method and DNA sequence analysis results in the identification of non-tuberculous mycobacteria.

The typing of non-tuberculous mycobacteria (NTM) is important from a clinical and epidemiological perspective. The polymerase chain reaction-restriction enzyme analysis (PRA) method and DNA sequence analysis method were utilized to target a gene region that codes the 65-kDa heat-shock protein for typing 150 suspected NTM samples isolated from the respiratory tract. Mycobacterium abscessus, Mycobacterium xenopi, Mycobacterium fortuitum, and Mycobacterium peregrinum were most frequently found by both methods. Six isolates that could not be defined by the PRA method were defined as Nocardia cyriacigeorgica, Nocardia abscessus, and Mycobacterium intracellulare by DNA sequence analysis. Discordance between the results of the two methods was observed for only one isolate. The isolate that was defined as Mycobacterium gordonae type 6 by the PRA method was defined as Mycobacterium senegalense by sequence analysis. The PRA method is simple and gives rapid results. Compared with DNA sequence analysis, it gives consistent and reliable results up to a ratio of 90%. DNA sequence analysis is the gold standard method in which all strains can be defined. However, given our laboratory conditions, its disadvantage is that it takes longer to reach a diagnosis than through the PRA method.

The role of molds in the relation between indoor environment and atopy in asthma patients.

BACKGROUND: The effect of mold fungi to allergic sensitization is not well-known. We aimed to evaluate the role of molds in the relation between indoor environment and atopy in asthmatics. MATERIALS AND METHODS: The air samples obtained from 66 stable asthmatics and 35 control subject's houses were sprayed into Sabouraud dextrose agar. Allergy skin testing were performed in both groups. The temperature and humidity of each house were measured. RESULTS: The incidence of atopy was similar in cases (59.1%) and controls (51.4%). The average amount of mold was 35.9 CFU/m(3) and 34.3 CFU/m(3), respectively. The number of household residents was positively correlated with the amount of molds. There was no difference in the amount of mold with respect to dosage of inhaler corticosteroids as well as symptom levels in asthmatics. The most frequently encountered allergens were Dermatophagoides farinae/Dermatophagoides pteronyssinus, grass/weeds and molds. Spending childhood in a village was more common among atopics. CONCLUSION: Living environment during the childhood might affect atopy and asthma. Based on the identification of molds as the second most frequent allergen after mites in our study population, assessment of mold sensitization as well as in forming patients about ways to avoid them seem likely to contribute to the effective management of uncontrolled asthma.