Evaluation of Etest for susceptibility testing of rapidly growing mycobacteria

Biehle, J R; Cavalieri, S J; Saubolle, Michael A.; Getsinger, L.

doi:10.1128/jcm.33.7.1760-1764.1995

Cited by 30 publications

(21 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Drug susceptibility testing (DST), was performed on the M. abscessus subsp. abscessus isolate using the E-test (AB Biodisk, Solna, Sweden) and the broth microdilution methods, the former with both 4 day and 14 day readings (Sensititre, Trek Diagnostic Systems, USA) [20,21]. Results were evaluated according to the breakpoints reported in the CLSI document from 2011 (Table 2) [19].…”

Section: Case Reportmentioning

confidence: 99%

Treating Primary Arthroprosthesis Infection Caused byMycobacterium abscessussubsp. abscessus

Pace

Antinolfi

Borroni

et al. 2019

Case Reports in Infectious Diseases

View full text Add to dashboard Cite

Prosthetic joint infections (PJI) caused by nontuberculous mycobacteria are very rare, and results of treatment can be unpredictable. A 72-year-old female underwent hip replacement after an accidental fall in a local hospital in Santo Domingo. The postoperative period was uneventful except for a traumatic wound near the surgical scar. PJI caused by Mycobacterium abscessus subsp. abscessus was diagnosed 6 months later. A two-stage reimplantation was performed after a 3-month period of aetiology-directed therapy, including amikacin, imipenem, and clarithromycin. M. abscessus isolate was reported to be resistant to clarithromycin when incubation was protracted for 14 days and to harbour the gene erm(41). The patient manifested major side effects to tigecycline. At reimplant, microbiologic investigations resulted negative. Overall, medical treatment was continued for a 7-month period. When discontinued and at 6-month follow-up, the patient was clinically well, inflammatory markers were normal, and the radiography showed well-positioned prosthesis. Mycobacterium abscessus subsp. abscessus is a very rare cause of PJI, yet it must be included in the differential diagnosis, especially when routine bacteria cultures are reported being negative. Further investigations are needed to determine any correlations between clinical results and in vitro susceptibility tests, as well as the clinical implications of M. abscessus subsp. abscessus harbouring the functional gene erm(41). Moreover, investigations are needed for determine optimal timings of surgery and lengths of medical therapy to improve patient outcome.

show abstract

Section: Case Reportmentioning

confidence: 99%

Treating Primary Arthroprosthesis Infection Caused byMycobacterium abscessussubsp. abscessus

Pace

Antinolfi

Borroni

et al. 2019

Case Reports in Infectious Diseases

View full text Add to dashboard Cite

show abstract

“…Etest (AB BIODISK, Solna, Sweden), an accurate MIC method, has emerged as the method of choice for the susceptibility testing of fastidious organisms (16), including rapidly growing mycobacteria (2,5,11). Preliminary results have shown that Etest is a promising new method for the susceptibility testing of more slowly growing mycobacteria as well (19).…”

mentioning

confidence: 99%

Testing of Mycobacterium tuberculosis susceptibility to ethambutol, isoniazid, rifampin, and streptomycin by using Etest

Wanger¹,

Mills²

1996

J Clin Microbiol

View full text Add to dashboard Cite

Etest (AB BIODISK, Solna, Sweden) is a precise MIC method and the practical method of choice for the susceptibility testing of many fastidious organisms, including rapidly growing mycobacteria. Methods recommended by the National Committee for Clinical Laboratory Standards for the susceptibility testing of Mycobacterium tuberculosis include the Bactec (Becton Dickinson, Sparks, Md.) broth and agar proportion methods. A comparison of Etest with the Bactec broth method for testing the susceptibility of M. tuberculosis to four first-line antituberculous agents demonstrated equivalent interpretive results for 100% of the isolates tested. Agreements with agar proportion MICs, within ؎ 2 log 2 dilutions, were 90, 93, 100, and 94% for ethambutol, isoniazid, rifampin, and streptomycin, respectively. Etest MICs were easily read within 5 to 10 days of inoculation. Preparation of the inoculum with a turbidity equivalent to a McFarland 3.0 standard prepared from growth on an agar surface and with a broth with a Bactec growth index of >999 yielded equivalent results. Clinical isolates for which the MICs were reproducible were also identified as possible quality control strains. The Etest method appears to be an alternative method for testing the susceptibility of M. tuberculosis isolates to the four most commonly used therapeutic agents.

show abstract

“…Susceptibility testing of clinically significant isolates of the rapidly growing mycobacteria is recommended because these organisms differ in susceptibility to the antimicrobial agents commonly used for therapy (2,4,(11)(12)(13)(14)(15)(16). Based on data from the Centers for Disease Control and Prevention, many laboratories in the United States do such testing by a variety of methods (21).…”

Section: Discussionmentioning

confidence: 99%

“…The problem with the existing cefoxitin breakpoints is that the resistance breakpoint (64 g/ml) is in the middle of the normal MIC range for untreated isolates of several of the rapidly growing mycobacteria. Previous studies have demonstrated that the cefoxitin MICs for more than 90% of isolates of M. fortuitum and M. abscessus range from 16 to 64 g/ml, with a mode of 32 g/ml (2,12,14). a For laboratories that infrequently isolate rapidly growing mycobacteria, sending isolates to an experienced reference laboratory is recommended.…”

Section: Discussionmentioning

confidence: 99%

“…For this reason, antimicrobial susceptibility testing of isolates considered clinically significant is recommended. Various methods of testing susceptibility of the rapidly growing mycobacteria have been described, including agar disk elution, broth microdilution, and the E-test (2,3,11,17). Currently, however, no standardized testing method for this group of organisms exists, nor has the interlaboratory reproducibility of any method been assessed.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Multisite Reproducibility of Results Obtained by the Broth Microdilution Method for Susceptibility Testing of Mycobacterium abscessus , Mycobacterium chelonae , and Mycobacterium fortuitum

et al. 1999

View full text Add to dashboard Cite

A multicenter study was conducted to assess the interlaboratory reproducibility of broth microdilution testing of the more common rapidly growing pathogenic mycobacteria. Ten isolates (fourMycobacterium fortuitum group, three Mycobacterium abscessus, and three Mycobacterium chelonae isolates) were tested against amikacin, cefoxitin, ciprofloxacin, clarithromycin, doxycycline, imipenem, sulfamethoxazole, and tobramycin (M. chelonae only) in four laboratories. At each site, isolates were tested three times on each of three separate days (nine testing events per isolate) with a common lot of microdilution trays. Agreement among MICs (i.e., mode ± 1 twofold dilution) varied considerably for the different drug-isolate combinations and overall was best for cefoxitin (91.7 and 97.2% for one isolate each and 100% for all others), followed by doxycycline, amikacin, and ciprofloxacin. Agreement based on the interpretive category, using currently suggested breakpoints, also varied and overall was best for doxycycline (97.2% for one isolate and 100% for the rest), followed by ciprofloxacin and clarithromycin. Reproducibility among MICs and agreement by interpretive category was most variable for imipenem. Based on results reported from the individual sites, it appears that inexperience contributed significantly to the wide range of MICs of several drugs, especially clarithromycin, ciprofloxacin, and sulfamethoxazole. New interpretive guidelines are presented for the testing of M. fortuitum against clarithromycin; M. abscessus andM. chelonae against the aminoglycosides; and all three species against cefoxitin, doxycycline, and imipenem.

show abstract

Evaluation of Etest for susceptibility testing of rapidly growing mycobacteria

Cited by 30 publications

References 13 publications

Treating Primary Arthroprosthesis Infection Caused byMycobacterium abscessussubsp. abscessus

Treating Primary Arthroprosthesis Infection Caused byMycobacterium abscessussubsp. abscessus

Testing of Mycobacterium tuberculosis susceptibility to ethambutol, isoniazid, rifampin, and streptomycin by using Etest

Multisite Reproducibility of Results Obtained by the Broth Microdilution Method for Susceptibility Testing of Mycobacterium abscessus , Mycobacterium chelonae , and Mycobacterium fortuitum

Contact Info

Product

Resources

About