Structural Analysis of Biofilm Formation by Rapidly and Slowly Growing Nontuberculous Mycobacteria

Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
Applied and Environmental Microbiology (Impact Factor: 3.67). 03/2009; 75(7):2091-8. DOI: 10.1128/AEM.00166-09
Source: PubMed

ABSTRACT Mycobacterium avium complex (MAC) and rapidly growing mycobacteria (RGM) such as M. abscessus, M. mucogenicum, M. chelonae, and M. fortuitum, implicated in health care-associated infections, are often isolated from potable water supplies as part of the microbial flora. To understand factors that influence growth in their environmental source, clinical RGM and slowly growing MAC isolates were grown as biofilm in a laboratory batch system. High and low nutrient levels were compared, as well as stainless steel and polycarbonate surfaces. Biofilm growth was measured after 72 h of incubation by enumeration of bacteria from disrupted biofilms and by direct quantitative image analysis of biofilm microcolony structure. RGM biofilm development was influenced more by nutrient level than by substrate material, though both affected biofilm growth for most of the isolates tested. Microcolony structure revealed that RGM develop several different biofilm structures under high-nutrient growth conditions, including pillars of various shapes (M. abscessus and M. fortuitum) and extensive cording (M. abscessus and M. chelonae). Although it is a slowly growing species in the laboratory, a clinical isolate of M. avium developed more culturable biofilm in potable water in 72 h than any of the 10 RGM examined. This indicates that M. avium is better adapted for growth in potable water systems than in laboratory incubation conditions and suggests some advantage that MAC has over RGM in low-nutrient environments.

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Available from: Matthew Arduino, Jan 24, 2014
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    • "M. chelonae has been linked with all types of surgical infections, including eye, head and neck, cardiovascular and chest, abdominal, cosmetic and reconstructive, and orthopedic procedures. M. chelonae has a hydrophobic cell wall that allows it to adhere to multiple surface types, forming biofilms with significant cording.5 Therefore, procedures involving foreign materials, artificial prostheses, and implantable devices are particularly at risk. "
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    ABSTRACT: Mycobacterium chelonae is a rapidly growing nontuberculous Mycobacterium and an uncommon cause of aggressive, treatment-resistant ocular and periocular infection. This is the first known case report of a woman who developed unilateral M. chelonae dacryocystitis after undergoing endoscopic sinus surgery and right endoscopic dacryocystorhinostomy (DCR) with Crawford stent placement. We describe our findings and effective methods to manage the infection. Three weeks after undergoing DCR, the patient acutely developed symptoms consistent with dacryocystitis. The patient was treated with broad-spectrum antibiotics followed by incision and drainage of the dacryocystocele abscess, with initial cultures showing no organisms. With continued signs of infection, the Crawford stent was later removed. Cultures eventually grew M. chelonae and the patient was treated with 4 months of antibiotic therapy. While receiving antibiotics, the patient developed three abscesses along the inferior lid requiring excision. After 21 months, the patient remains free of infection and has not experienced any other complications. This case serves as a reminder to consider M. chelonae as a potential cause of periocular infection, which may be more likely to occur postoperatively with indwelling devices, as well as in patients with sinonasal issues requiring nasal irrigations. This organism can be difficult to treat because of multidrug resistance and biofilm production. Recommended therapy includes surgical debridement, removal of any implanted devices, and a two-drug antibiotic regimen for at least 4 months.
    03/2014; 5(2). DOI:10.2500/ar.2014.5.0081
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    • "NTM cell surface hydrophobicity allows the attachment of these microorganisms to surfaces and favors their capacity for biofilm formation, particularly under low-nutrient conditions [34,35]. Therefore, it seems that NTM are not transient contaminants of drinking water distribution systems but rather that they grow and persist in household plumbing [7,11]. "
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    ABSTRACT: Nontuberculous mycobacteria (NTM) are environmental opportunistic pathogens found in natural and human-engineered waters, including drinking water distribution systems and household plumbing. This pilot study examined the frequency of occurrence of NTM in household potable water samples in Mexico City. Potable water samples were collected from the "main house faucet" and kitchen faucet. The presence of aerobic-mesophilic bacteria (AMB), total coliforms (TC), fecal coliforms (FC) and NTM species were determined. Mycobacteria species were identified by PCR restriction enzyme pattern analysis (PRA) of the 65-kDa heat shock protein gene (hsp65) and sequencing of the hypervariable region 2 (V2) of the 16S rRNA gene and of the rpoB gene. AMB (<100 CFU/ml) were present in 118 out of 120 samples; only two samples were outside guidelines ranges (>100 CFU/ml). TC and FC were detected in four and one samples, respectively. NTM species were recovered from 16% samples (19/120) and included M. mucogenicum (nine), M. porcinum (three), M. avium (three), M. gordonae (one), M. cosmeticum (one), M. fortuitum (one), and Mycobacterium sp (one). All household water samples that contained NTM complied with the standards required to grade the water as "good quality" potable water. Household potable water may be a potential source of NTM infection in Mexico City.
    BMC Research Notes 12/2013; 6(1):531. DOI:10.1186/1756-0500-6-531
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    • "nces in the log density of the biofilm of the four species were caused by differences in growth rate , rather than an antagonistic effect of one species toward another in the biofilm . Recovery effi - ciency of NTM biofilm from plastic and stainless steel coupon surfaces by the current method was determined previously to range between 90 and 99% ( Williams et al . 2009 ) , indicating consistency in the processing protocol ."
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    ABSTRACT: Water in healthcare environments can be a source for healthcare-associated infections (HAI). However, information on the exposure risk to opportunistic pathogens in potable water distribution systems (PWDS) is lacking. Laboratory studies characterizing the interaction of opportunistic pathogens with biofilms are needed to understand their role in water systems within healthcare facilities. A stable, repeatable, PWDS multi-species biofilm model comprising Sphingomonas paucimobilis, Methylobacterium sp., Delftia acidovorans, and Mycobacterium mucogenicum was developed in the CDC Biofilm Reactor (CBR), reaching 6 log(10) CFU cm(-2) within 6 days. The model was used to investigate the interaction of the opportunistic pathogen M. mucogenicum with the other species, and to determine the efficacy of monochloramine (NH(2)Cl) as a disinfectant against 2-week-old biofilms. Addition of 1 or 2 mg l(-1) NH(2)Cl resulted in the same or an increased log density of viable M. mucogenicum in the biofilm while inactivating some of the Proteobacteria. Although M. mucogenicum preferentially resided in the biofilm, NH(2)Cl exposure caused release of viable M. mucogenicum from the biofilm into the water. Additional studies with this model should determine if sodium hypochlorite has a comparative effect and if other nontuberculous mycobacteria (NTM) respond to NH(2)Cl similarly.
    Biofouling 11/2012; 28(10):1129-39. DOI:10.1080/08927014.2012.735231 · 3.42 Impact Factor
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