Epidemic of Postsurgical Infections Caused by Mycobacterium massiliense

Abstract

An epidemic of infections after video-assisted surgery (1,051 possible cases) caused by rapidly growing mycobacteria (RGM) and involving 63 hospitals in the state of Rio de Janeiro, Brazil, occurred between August 2006 and July 2007. One hundred ninety-seven cases were confirmed by positive acid-fast staining and/or culture techniques. Thirty-eight hospitals had cases confirmed by mycobacterial culture, with a total of 148 available isolates recovered from 146 patients. Most (n ‫؍‬ 144; 97.2%) isolates presented a PRA-hsp65 restriction pattern suggestive of Mycobacterium bolletii or Mycobacterium massiliense. Seventy-four of these isolates were further identified by hsp65 or rpoB partial sequencing, confirming the species identification as M. massiliense. Epidemic isolates showed susceptibility to amikacin (MIC at which 90% of the tested isolates are inhibited [MIC 90 ], 8 g/ml) and clarithromycin (MIC 90 , 0.25 g/ml) but resistance to ciprofloxacin (MIC 90 , >32 g/ml), cefoxitin (MIC 90 , 128 g/ml), and doxycycline (MIC 90 , >64 g/ml). Representative epidemic M. massiliense isolates that were randomly selected, including at least one isolate from each hospital where confirmed cases were detected, belonged to a single clone, as indicated by the analysis of pulsed-field gel electrophoresis (PFGE) patterns. They also had the same PFGE pattern as that previously observed in two outbreaks that occurred in other Brazilian cities; we designated this clone BRA100. All five BRA100 M. massiliense isolates tested presented consistent tolerance to 2% glutaraldehyde. This is the largest epidemic of postsurgical infections caused by RGM reported in the literature to date in Brazil.Outbreaks, pseudooutbreaks, and cases of health-care-associated infections caused by rapidly growing mycobacteria (RGM) have been reported since the first case was described in 1938 (13). In virtually all nosocomial infections caused by this group of microorganisms, there were failings in the sterilization processes of solutions, surgical instruments, or medical devices (13,14,45). Recent publications indicate an increasing number of infections secondary to breast augmentation and video-assisted surgeries (7,9,19,23,25,(40)(41)(42)(43).The growing number of cases and reports may be due, at least in part, to the well-known tolerance to alkaline glutaraldehyde among Mycobacterium chelonae-Mycobacterium abscessus group isolates and to the low susceptibility to high-level disinfectants (20,22,39).Outbreaks of RGM infections unrelated to medical procedures also can occur and usually are associated with exposure to recreational water containing a large number of bacteria and inadequate chlorination (15,44), highlighting the ubiquity of these organisms in the environment. In fact, RGM have been recovered from many different environmental sources, including soil and water distribution systems (8,45). RGM are considered opportunistic pathogens and can cause chronic lung disease, particularly the species included in the M. chelonae-M. abscessus group (8, 46)...

Mycobacterium massiliense BRA100 strain recovered from postsurgical infections: resistance to high concentrations of glutaraldehyde and alternative solutions for high level disinfection

“…Representative isolates were identified as M. massiliense and belonged to a single clone named BRA100, which was genotypically identical to isolates obtained from previous outbreaks. Our results showed that M. massiliense BRA100 strain was also resistant to 2% glutaraldehyde (GTA) commercial solutions, commonly used for preoperative high-level disinfection in Brazil 10,11 .…”

“…Representative isolates (CRM -0018 and CRM -0019), recovered from biopsies during the epidemic of postsurgical infections after videolaparoscopic procedures in the state of Rio de Janeiro (2006)(2007), and previously identified as belonging to M. massiliense BRA100 strain were used for this investigation 10 . Additionally, M. massiliense isolate (CRM -270) obtained from sputum of non-epidemiologically related patient and not belonging to BRA100 clone was also evaluated.…”

“…The MIC of GTA against reference and clinical mycobacteria were evaluated concerning their ability to survive after 30 min of exposure to 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, 6.0%, 7.0% and 8.0% by using qualitative test protocols 10,12,13 . The above decribed solutions were obtained by diluting two concentrated commercial solutions prepared as recommended by the manufacturers.…”

“…The susceptibility of representative M. massiliense strains to 0.55% OPA and 3 different PA -based commercial solutions was also determined by using qualitative test assays previously described 10,12,13 . The strains were evaluated concerning their ability to survive after 15 and 30 min of exposure to disinfectant solutions using the suspension method, as recommended by the manufacturers and ANVISA for high-level disinfection.…”

“…Out of the confirmed patient-cases submitted to video laparoscopic surgery during this period of time, 148 RGM isolates were recovered and characterized, including one isolate obtained from surgical instruments 10 . Representative isolates were identified as M. massiliense and belonged to a single clone named BRA100, which was genotypically identical to isolates obtained from previous outbreaks.…”