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At least 19 recordsLinked to original sources
PubMed1990

High-performance liquid chromatography patterns of mycolic acids as criteria for identification of Mycobacterium chelonae, Mycobacterium fortuitum, and Mycobacterium smegmatis.

Rapidly growing mycobacteria of clinical significance were identified by mycolic acids detected with high-performance liquid chromatography. Mycolic acids from whole cells were extracted, derivatized, and detected by a modified high-performance liquid chromatography procedure in less than 3 h. Use of an internal standard allowed differentiation of Mycobacterium chelonae and Mycobacterium fortuitum by comparison of relative retention times. Peak height ratios were used for subidentification of M. chelonae strains; however, M. fortuitum and Mycobacterium smegmatis could not be separated by this system.

Chromatography, High Pressure Liquid↗
PubMed1987

In vitro susceptibility of Mycobacterium fortuitum, Mycobacterium chelonae and Mycobacterium avium against some quinolones.

The in vitro susceptibility of Mycobacterium fortuitum, Mycobacterium chelonae and Mycobacterium avium to ciprofloxacin, norfloxacin and ofloxacin was studied by the agar dilution method. All strains of Mycobacterium fortuitum were inhibited by 2 mg/ml or less of these antimicrobial agents. Concentrations higher than achievable blood levels were necessary to inhibit Mycobacterium chelonae and Mycobacterium avium.

Anti-Bacterial Agents↗
PubMed2005

Mycobacterium chelonae-Mycobacterium abscessus complex clear corneal wound infection with recurrent hypopyon and perforation after phacoemulsification and intraocular lens implantation.

We report a clear corneal wound infection occurring in a 74-year-old man caused by a member of the Mycobacterium chelonae-Mycobacterium abscessus complex, presenting as crystalline keratopathy with recurrent hypopyon. This led to perforation after phacoemulsification with posterior chamber intraocular lens implantation. Only after corneal biopsy of the incision was the causative organism isolated and found to be sensitive to clarithromycin and ciprofloxacin. Despite aggressive therapy, a full-thickness corneal perforation developed, requiring emergent cyanoacrylate glue to preserve ocular integrity. Both the difficulty and delays in obtaining a correct diagnosis led to severe ocular morbidity. Infectious lamellar keratitis limited to the clear cornea phacoemulsification incision is rare, but some unusual organisms such as atypical mycobacteria may be encountered.

Aged↗
PubMed1990

[Inner ear damage induced by bacteria (Mycobacterium chelonae)].

Mycobacterium chelonae has a pathogenicity for mouse inner ear, resulting in "spinning disease". The mice were subjected to intravenous injection of 1-1.2 x 10(7) organisms of strain ATCC19977 of M. chelonae subspecies abscessus. Morphological changes in the inner ear were investigated together with changes in behavior and auditory brainstem response (ABR). Three days after injection, the threshold of ABR rose in high frequency and the latency of the fifth wave prolonged. The behaviors of the mice such as "grooming" or "sniffing" were suppressed day by day. Fourteen days after injection, 35% of mice showed abnormal behavior, such as "spinning disease". The damage in the cochlear and vestibular sensory cells were observed using scanning electron microscopy and light microscopy. The inner ear showed serous or purulent labyrinthitis after injection. The most specific change found in purulent labyrinthitis was massive abscess of the cochlea with necrosis. Serous labyrinthitis which might have been induced by bacterial toxins was characterized by homogeneous and eosinophilic precipitates and slight cellular infiltrations in the perilymphatic and endolymphatic spaces. In the organ of Corti, the inner and outer hair cell cilia had degenerated and disappeared. In the vestibular end organs, the sensory cilia were fused, lost and sustained ballooning. The cross links and rough nature of the sensory hair membrane had disappeared in the early stage of serous labyrinthitis.

Animals↗
PubMed2003

Large-restriction-fragment polymorphism analysis of Mycobacterium chelonae and Mycobacterium terrae isolates.

Mycobacterium chelonae and Mycobacterium terrae were reported to be frequently present in the environment of the Mycobacterium bovis BCG trial area in south India. Six isolates of M. chelonae and four isolates of M. terrae obtained from different sources in this area were analyzed by pulsed-field gel electrophoresis (PFGE) to examine large-restriction-fragment (LRF) polymorphism using the chromosomal DNA digested with DraI and XbaI restriction enzymes. With the exception of one isolate of M. terrae, DNA from all other isolates could be digested with DraI and XbaI and resulted in separable fragments. Visual comparison of the LRFs showed a unique pattern for each of the isolates tested. A computer-assisted dendrogram of the percent similarity demonstrated a high degree of genetic diversity in this group of isolates. This study demonstrates that species of nontuberculous mycobacteria, particularly M. chelonae and M. terrae, can be successfully typed by their LRF pattern using PFGE, which does not require species-specific DNA probes.

BCG Vaccine↗
PubMed1993

DNA large restriction fragment patterns of sporadic and epidemic nosocomial strains of Mycobacterium chelonae and Mycobacterium abscessus.

Large restriction fragment (LRF) pattern analysis of genomic DNA using pulsed-field gel electrophoresis was performed on three reference strains, 32 sporadic isolates, and 92 nosocomial isolates from 12 epidemics of Mycobacterium chelonae and Mycobacterium abscessus. Only 17 of 30 (57%) unrelated strains of M. abscessus, compared with 10 of 11 (91%) of M. chelonae strains, gave satisfactory DNA extractions, with the remainder resulting in highly fragmented DNA. DraI, AsnI, XbaI, and SpeI gave satisfactory LRF patterns. Sporadic isolates of the two species had highly variable LRF patterns, except for one reference strain and one sporadic isolate of M. chelonae that differed by only two to five bands. Evaluation of repeat isolates from five patients monitored for 8 months to 13 years (mean, 5.8 years) revealed LRF patterns to be stable, with changes of not more than two bands. LRF analysis of the seven nosocomial outbreaks with evaluable DNA revealed identical patterns in most or all of the patient isolates and in three outbreaks revealed identity with environmental isolates. These outbreaks included endoscope contamination, postinjection abscesses, and surgical wound infections. LRF analysis of genomic DNA is a useful technique for epidemiologic studies of M. abscessus and M. chelonae, although improved technology is needed for the approximately 50% of strains of M. abscessus with unsatisfactory DNA extractions.

Cross Infection↗
PubMed2003

Lipomannans, but not lipoarabinomannans, purified from Mycobacterium chelonae and Mycobacterium kansasii induce TNF-alpha and IL-8 secretion by a CD14-toll-like receptor 2-dependent mechanism.

Lipoarabinomannans (LAMs) are glycolipids from the mycobacterial cell wall that exhibit various biological activities, including proinflammatory and anti-inflammatory responses. However, little is known about the properties of lipomannans (LMs), considered to be precursors of LAMs. In this study, we provide evidence that LMs purified from Mycobacterium chelonae and a clinical strain of Mycobacterium kansasii stimulated mRNA expression and secretion of TNF-alpha and IL-8 from human macrophage-like differentiated THP-1 cells. In contrast to LMs, LAMs were not able to induce a significant cytokine-inducing effect. The mechanism of activation by LMs was investigated using various Abs raised against surface receptors for multiple bacterial products. The presence of anti-CD14 or anti-Toll-like receptor 2 (TLR2) Abs profoundly affected production of TNF-alpha and IL-8, suggesting that both CD14 and TLR2 participate in the LM-mediated activation process. Furthermore, stimulation of cells was dependent on the presence of the LPS-binding protein, a plasma protein that transfers glycolipids to CD14. Chemical degradation of the arabinan domain of mannose-capped LAM from M. kansasii, which presented no cytokine-eliciting effect, restored the cytokine-inducing activity at a level similar to those of LMs. These results support the hypothesis that the presence of an arabinan in LAMs prevents the interaction of these glycolipids with TLR2/CD14 receptors. In addition, we found that phosphatidylinositol dimannosides isolated from M. kansasii did not induce cytokine secretion. This study suggests that LMs isolated from different mycobacterial species participate in the immunomodulation of the infected host and that the D-mannan core of this glycolipid is essential for this function.

Acute-Phase Proteins↗
PubMed2003

Effects of ortho-phthalaldehyde, glutaraldehyde and chlorhexidine diacetate on Mycobacterium chelonae and Mycobacterium abscessus strains with modified permeability.

The mechanisms of the mycobactericidal action of ortho-phthalaldehyde (OPA), glutaraldehyde (GTA) and chlorhexidine diacetate (CHA) were investigated using mycobacterial spheroplasts of two reference strains, Mycobacterium chelonae NCTC 946, Mycobacterium abscessus NCTC 10882 and two GTA-resistant strains, M. chelonae Epping and M. chelonae Harefield. Transmission electron microscopy of the spheroplasts revealed an altered cell wall structure compared with the parent cells. Structural alterations resulting from the spheroplasting process were in part correlated to a loss of lipid content. Low concentrations of CHA induced protein coagulation in M. chelonae NCTC 946 spheroplasts, which also exhibited the highest loss of free non-polar lipids. Higher concentrations of CHA were required to produce similar results to the other spheroplasts investigated in which there was a less substantial decrease in lipid content. OPA (0.5% w/v) readily penetrated the residual cell wall and cytoplasmic membrane, producing significant protein coagulation in M. chelonae NCTC 946. GTA (0.5% v/v) induced a similar effect but to a lesser extent. Pre-treatment of the spheroplasts with OPA and GTA and their subsequent suspension in water demonstrated that GTA was a more potent cross-linking agent. This protective effect of GTA results from extensive cross-linking of amino and/or sulphydryl side-chain groups of proteins. The rapid mycobactericidal effect of OPA probably arises from its more efficient penetration across biological membranes. Mycobacterial spheroplasts represented a useful cellular model with an altered cell wall permeability. This study also showed the importance of the mycobacterial cell wall in conferring intrinsic resistance to CHA.

Cell Wall↗
PubMed1999

Multisite reproducibility of results obtained by the broth microdilution method for susceptibility testing of Mycobacterium abscessus, Mycobacterium chelonae, and Mycobacterium fortuitum.

A multicenter study was conducted to assess the interlaboratory reproducibility of broth microdilution testing of the more common rapidly growing pathogenic mycobacteria. Ten isolates (four Mycobacterium 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 and M. chelonae against the aminoglycosides; and all three species against cefoxitin, doxycycline, and imipenem.

Amikacin↗
PubMed2000

Multisite reproducibility of Etest for susceptibility testing of Mycobacterium abscessus, Mycobacterium chelonae, and Mycobacterium fortuitum.

A multicenter study was conducted to assess the inter- and intralaboratory reproducibility of the Etest for susceptibility testing of the rapidly growing mycobacteria. The accuracy also was evaluated by comparing Etest results to those obtained by broth microdilution. Ten isolates (four of the Mycobacterium fortuitum group, three of Mycobacterium abscessus, and three of Mycobacterium chelonae) were tested against amikacin, cefoxitin, ciprofloxacin, clarithromycin, doxycycline, imipenem, and trimethoprim-sulfamethoxazole in each of four laboratories. At each site, isolates were tested three times on each of three separate days (nine testing events per isolate) using common lots of media and Etest strips. Interlaboratory agreement among MICs (i.e., mode +/- 1 twofold dilution) varied for the different drug-isolate combinations and overall was best for trimethoprim-sulfamethoxazole (75% for one isolate and 100% for all others), followed by doxycycline and ciprofloxacin. Interlaboratory agreement based on interpretive category also varied and overall was best for doxycycline (100% for all isolates), followed by trimethoprim-sulfamethoxazole and ciprofloxacin. Interlaboratory reproducibility among MICs was most variable for imipenem, and agreement by interpretive category was lowest for imipenem and amikacin. Modal Etest MICs agreed with those by broth microdilution only for doxycycline and the sulfonamides. For all other drugs, the modal MICs by the two methods differed by more than +/- 1 twofold dilution for one or more isolates. In all cases, the Etest MIC was higher and would have caused reports of false resistance. In summary, the Etest in this evaluation did not perform as well as broth microdilution for susceptibility testing of the rapidly growing mycobacteria. It was problematic for most species and drugs, primarily because of a trailing endpoint and/or high MICs compared to broth. Its use will necessitate further investigation, including determination of the optimal medium and incubation conditions and clarification of endpoint interpretation.

Anti-Bacterial Agents↗
PubMed1996

Genetic basis for clarithromycin resistance among isolates of Mycobacterium chelonae and Mycobacterium abscessus.

Resistance to clarithromycin among isolates of Mycobacterium chelonae and M. abscessus was observed in 18 of 800 (2.3%) patients tested between 1990 and 1995. Patients whose isolates were resistant had either disseminated disease or chronic lung disease, and the resistant isolates were recovered after clarithromycin monotherapy. Sequencing of the gene coding for the 23S rRNA peptidyltransferase region revealed a point mutation involving adenine at position 2058 (38%) or adenine at position 2059 (62%) in 20 of 20 relapse isolates from the first 13 patients identified. By pulsed-field gel electrophoresis or random amplified polymorphic DNA PCR, initial and relapse isolates were shown to have identical DNA patterns. M. chelonae and M. abscessus isolates were found to have only a single chromosomal copy of the rRNA operon, thus making them susceptible to single-step mutations. Thus, clarithromycin resistance in these species of rapidly growing mycobacteria relates to a point mutation in the gene coding for 23S rRNA and occurs in limited clinical situations, but was identified in almost 5% of isolates tested in 1995.

Blotting, Southern↗
PubMed2006

Enterobacterial repetitive intergenic consensus PCR is a useful tool for typing Mycobacterium chelonae and Mycobacterium abscessus isolates.

Outbreaks of rapidly growing mycobacterium (RGM) infections are increasingly being reported worldwide. Information about genetic relatedness of isolates obtained during outbreaks can provide opportunities for prompt intervention. Pulsed-field gel electrophoresis (PFGE) is expensive, time consuming, and labor intensive. Other than that, Mycobacterium abscessus isolates can suffer DNA degradation during electrophoresis. Polymerase chain reaction (PCR)-based methods are cheaper, faster, and easier to perform, but discriminatory power varies depending on the primer used. In this study, we tested the competence of enterobacterial repetitive intergenic consensus (ERIC) PCR in comparison with PFGE to distinguish unrelated isolates (24 Mycobacterium chelonae and 24 M. abscessus) obtained from human and/or environmental samples and to group 56 isolates from 6 outbreaks confirmed epidemiologically, caused by M. chelonae and M. abscessus after ophthalmologic refractive surgery and mesotherapy. Enterobacterial repetitive intergenic consensus PCR presented discriminatory power, calculated using Simpson's index of diversity, of 0.989 for M. abscessus and 0.975 for M. chelonae and grouped outbreak isolates in distinct groups showing epidemiologic concordance. Pulsed-field gel electrophoresis also grouped outbreak isolates and presented discriminatory power of 0.972 and 0.993 for M. abscessus and M. chelonae, respectively. DNA from 8 (22%) of 36 M. abscessus isolates analyzed showed degradation during electrophoresis. Compared with PFGE and epidemiologic information as the gold standard, ERIC PCR is a simple, high throughput, affordable, reproducible, and discriminatory molecular typing method for inference of genetic relatedness of RGMs of the M. chelonae-abscessus group.

Bacteriological Techniques↗
PubMed2000

Cluster of cases of Mycobacterium chelonae bacteraemia.

Mycobacterium chelonae was isolated from the blood of four immunosuppressed patients over a period of 10 weeks. Three patients had intravascular catheters in situ and the other had a biliary stent. All presented with recurrent fever despite treatment with broad-spectrum antibiotics. Blood cultures using standard bacteriological medium yielded a gram-positive bacillus from each patient. Ziehl-Neelsen staining of these cultures demonstrated a branching acid-fast bacillus that was subsequently identified as Mycobacterium chelonae in each case. The isolates were sensitive to clarithromycin and, although success of treatment with clarithromycin monotherapy has been variable, this antibiotic combined with removal of the intravascular catheters was used to treat those three patients. The treatment was successful with no recurrence of symptoms after 12 months of follow-up. The patient with the biliary stent died soon after Mycobacterium chelonae was isolated. Pyrolysis mass spectrometry analysis indicated the isolates were of two distinct strains. Radiological insertion of the Hickman lines and biliary stent was implicated epidemiologically as the source of infection.

Adult↗
PubMed1990

Immunomodulatory properties of a strain of Mycobacterium chelonae--II. Qualitative and quantitative stimulation of mouse splenocytes by Mycobacterium chelonae.

Intraperitoneal [i.p.] and subcutaneous [s.c.] administration to BALB/C mice with a single dose of 5 mg/kg body weight (wet weight) of live Mycobacterium chelonae (Mch) augmented splenocyte blastogenesis. Similar increases in splenocyte blastogenesis manifested during a single oral administration to mice with 100 mg/kg body weight (wet weight) of this Mycobacterium. When splenocytes issued from these mice are activated by mitogens, a highly significant enhancement of lymphoblastic transformation was observed. On the other hand, multiple oral administrations with 50 mg/kg body weight (wet weight) to Mch/dose did not manifest statistically significant differences in splenocyte blastogenesis as compared to controls. Meanwhile, a highly increased transformation of splenocytes, issued from such mice, is observed in response to lectins and to the mitogenic effect of this microorganism. Splenocyte counts have shown 44.5, 37.6, and 23.2% increases in response to i.p., s.c. and multiple oral administration of this bacterium, respectively, as compared to solvent controls. Repeated s.c. administration of this mycobacterium manifested short lived and weak syndromes of anaphylactic shock during and immediately after the second inoculation of Mch. This phenomenon is not observed during repeated intraperitoneal and oral administrations. In conclusion, parenteral (i.p. and s.c.) and oral administration of Mch stimulates the immune system of mice. This effect is characterised by increased in vivo cell multiplication and by enhanced ex vivo DNA synthesis of murine splenocytes. The need of further studies is eminent to elucidate classes of immunocompetent cells involved in this phenomenon.

Animals↗
PubMed1996

[Postoperative infection with Mycobacterium chelonae].

A 70-year-old patient developed Mycobacterium chelonae infection at a donor vein graft site following cardiac bypass surgery. The infection presented as fibrinous, necrotic ulcerations in the scar area. Mycobacterium chelonae and mycobacterium fortuitum are atypical mycobacteria and have been described previously causing infections after injections or surgical procedures. Infection of donor vein graft site is a rare complication after cardiac surgery. As mycobacterium chelonae cannot be cultivated on normal culture media, delayed wound healing might be disinterpretated as a primary wound healing disorder. Treatment of atypical myobacteriosis includes antibiotics, local heat therapy and surgical excision. Clarithromycin is the antibiotic of choice. We obtained complete healing after two months of Clarithromycin treatment, combined with heat therapy.

Aged↗
PubMed2003

Mycobacterium chelonae osteoarthritis in a Kemp's ridley sea turtle (Lepidochelys kempii).

A stranded Kemp's ridley sea turtle (Lepidochelys kempii) was rescued and treated at the National Aquarium in Baltimore (Maryland, USA) for inappetence and epidermal appendicular and plastral lesions. After 4 mo of care, the turtle developed a swollen left elbow joint. Within 1 mo of initial swelling, osteolytic lesions developed in the proximal radius and ulna. The elbow joint was surgically debrided, flushed, and cultured. The incision dehisced 10 days after surgery. Mycobacterium chelonae was cultured from the left elbow joint and from a skin nodule of the dorsum of the right front flipper. The turtle was euthanized due to apparent systemic infection with M. chelonae. Mycobacterium chelonae was isolated from cultures taken at necropsy of the lung, liver, spleen, kidney, and pericardium. Osteoarthritic infections with M. chelonae have not been reported in reptiles. Additionally, primary osteoarthritic diseases of synovial joints are uncommon in reptilian species. Due to the paucity of reports of mycobacterial diseases in sea turtles, the continued documentation of these cases will increase knowledge and understanding in caring for these endangered animals.

Animals↗
PubMed1989

Mycobacterium chelonae keratitis.

A case of Mycobacterium chelonae keratitis is described. As with any infective keratitis, appropriate treatment depends upon rapid and accurate microbiological assessment of corneal scraping. Acid-fast stains such as Ziehl-Nielson should be performed, particularly in chronic corneal ulcers, as only these stains will distinguish mycobacteria from the more common diphtheroid organisms. The mycobacterium chelonae organism was sensitive only to tetracyclines.

Aged↗