Identification Of Clostridia Research Articles

Identification of Clostridium spp. derived from a sheep and cattle slaughterhouse by matrix-assisted laser desorption and ionization-time of flight mass spectrometry (MALDI-TOF MS) and 16S rDNA sequencing.

Using acut-off score of 1.7 was sufficient for accurate identification of Clostridium species. MALDI-TOF MS identification scores for Clostridium spp. decreased with longer incubation time. Clostridium species predominantly were isolated from carcasses after skinning and evisceration steps in the slaughterhouse. MALDI-TOF MS could be an accurate way to identify Clostridium species. Moreover, continuous improvement of the database and MALDI-TOF MS instrument enhance its performance in food control laboratories.

Comparing the identification of clostridium SPP. from blood culture using phenotypic, molecular, and two matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry methods: a detailed analysis including the impact of culture age and sample preparation on the peformance on MALDI-TOF systems

Introduction We compared the identification of 52 Clostridium species from 52 incident bacteraemic patients using phenotypic analysis, two MALDI-TOF mass spectrometry platforms and molecular sequencing. We also examined the impact of different sample preparations and (on one platform) days of colonial growth on the performance of MALDI-TOF systems. Result 16S rRNA PCR accurately identified 10 Clostridium species amongst the 52 isolates. Combination phenotypic methods identified 44/52 (84.6%) to species level. Spectrometric analysis using Vitek MS yielded 47/52 (90.4%) species using direct transfer (DT), whilst analysis using Bruker MS yielded correct identification dependent on sample preparation [69.2% for DT protocol, 100% for extended direct transfer (EDT) protocol and 100% for full formic extraction (EX) protocol]. Sample preparation didn’t impact the Vitek MS. There was at least moderate agreement in performance for DT, EDT and EX between different days for the Bruker MS. Conclusion Phenotypic identification required numerous methods to accurately identified Clostridium species. Vitek MALDI-TOF MS performed better with the DT protocol compared to the Bruker MS, but the latter yielded correct identification in all samples tested with EDT and EX protocol. Sample preparations did not impact the Vitek MS. On the Bruker MS, the testing cycle can begin upon view of colonial growth.

Post-traumatic bone and/or joint limb infections due to Clostridium spp.

Clostridium spp. are saprophytic Gram-positive bacteria found in soil and capable of generating endospores. Spore germination occurs when environmental conditions are favorable. Clostridium spp. can cause infections of compound fractures and deep wounds contaminated from soil micro-organisms. Clostridium spp. infections of traffic-related injuries are particularly severe events whose outcome is uncertain even with aggressive medical and surgical treatment. We retrospectively reviewed 12 patients (median age, 45 years) with Clostridium spp. bone and/or joint infections complicating compound limb fractures with soil contamination and extensive soft-tissue damage. Prophylactic amoxicillin-clavulanic acid therapy was administred, followed by emergency surgical wound debridment and lavage. Fracture fixation was performed immediately in nine patients (external in four and internal in five) or at a later time on three patients. The immediate outcome was unfavourable in all 12 cases, requiring early reoperation after a median of 10 days (range, 5-25 days). Median time to Clostridium strain identification was 14.5 days (range, 5-160). All infections were polymicrobial. Surgical wound excision, hardware removal (in four cases), and antibiotic therapy produced a favourable outcome in one patient, with no recurrence after 2 years of follow-up; the outcome was unfavourable in 11 cases, with delayed fracture union, septic non-union, impaired healing, and/or chronic sinus tract drainage. Several second-line treatments were used in these 11 patients: intramedullary nailing without bone grafting in four patients, with three failures; decortication and grafting in two patients, with failure in both; nailing with decortication in one patient, who had a good outcome; and the induced membrane procedure described by Masquelet in four patients, all of whom had good outcomes. After a median follow-up of 24 months (range, 18-53 months), the bone infection had subsided in eight patients. The remaining four patients had septic non-union. Clostridium spp. infections are particularly severe. The diagnosis is delayed and identification of the organism is challenging. The treatment is difficult and results in unfavorable outcomes in one-third of cases. The identification of Clostridium in specimens from an osteoarticular infection indicates a need for extremely extensive and aggressive surgical resection, as spore resistance may impair the in vivo efficacy of antimicrobial agents. IV (retrospective cohort study).

Development of a microarray for identification of pathogenic Clostridium spp.

In recent years, Clostridium spp. have rapidly reemerged as human and animal pathogens. The detection and identification of pathogenic Clostridium spp. is therefore critical for clinical diagnosis and antimicrobial therapy. Traditional diagnostic techniques for clostridia are laborious, are time consuming, and may adversely affect the therapeutic outcome. In this study, we developed an oligonucleotide diagnostic microarray for pathogenic Clostridium spp. The microarray specificity was tested against 65 Clostridium isolates. The applicability of this microarray in a clinical setting was assessed with the use of mock stool samples. The microarray was successful in discriminating at least 4 species with the limit of detection as low as 10 4 CFU/mL. In addition, the pattern of virulence and antibiotic resistance genes of tested strains were determined through the microarrays. This approach demonstrates the high-throughput detection and identification of Clostridium spp. and provides advantages over traditional methods. Microarray-based techniques are promising applications for clinical diagnosis and epidemiologic investigations.

Clostridial myonecrosis in horses (37 cases 1985-2000).

Previous reports of clostridial myonecrosis have either focused on individual case reports or have been small retrospective studies reporting very high mortality rates. The objective of this study was to describe the outcome of cases of clostridial myonecrosis submitted to 2 referral equine hospitals in the United States over a 15 year period. A retrospective study of case material selected on the basis of positive Clostridium spp. culture or the identification of Clostridium spp. by specific fluorescent antibody testing from soft tissue wounds was performed at Cornell and Wisconsin. 37 cases of clostridial myonecrosis were documented. Twenty-seven horses survived, 8 were subjected to euthanasia and 2 died during treatment for an overall survival rate of 73%. Twenty-five cases (68%) were associated with Clostridium perfringens alone, 6 cases (16%) with Cl. septicum alone, 4 cases with mixed clostridial infections (11%), 1 case with Cl. sporogenes and 1 with an unspeciated Clostridium spp. The highest survival rate of 81% was documented for those cases from which Cl. perfringens alone was isolated. The most common antecedent condition prior to referral was colic. The myonecrotic lesion occurred within 6-72 h of a soft tissue injection in 34 cases but was associated with a wound or laceration in the remaining 3 cases. Of the 34 cases associated with recent injections, 24 were associated with i.m. injections in the cervical region, 4 in the semimembranosus/semitendinosus region, 3 in the gluteal region, 2 with perivascular leakage of drugs administered into the jugular vein and 1 case developed simultaneously in the gluteal and neck region following injections at both sites. Clostridial myonecrosis can occur following the i.m. or inadvertent perivascular administration of a wide variety of commonly administered drugs. It is most common in the neck musculature. Aggressive treatment can be associated with survival rates of up to 81% for cases due to Cl. perfringens alone. Survival rates for other Clostridial spp. tend to be lower. A combination of high dose i.v. antibiotic therapy and surgical fenestration/debridement is the best approach to cases of clostridial myonecrosis. With rapid diagnosis and therapeutic intervention, horses may have up to an 81% chance of survival.

Isolation and identification of Clostridium spp. from infections associated with the injection of drugs: experiences of a microbiological investigation team.

Pathogenic species of the genus Clostridium may contaminate the materials used in the injection of drugs and under the right conditions may cause serious or life-threatening disease. C. novyi type A was implicated in an outbreak of severe infection with high mortality in injecting drug users who injected heroin extravascularly. The isolation of such highly oxygen-sensitive clostridia from clinical material may require adherence to enhanced methods and, once isolated, commercially available anaerobe identification kits alone may not give an accurate identification. Additional phenotypic tests that are useful in recognising the main pathogenic species are described. Differentiation of C. novyi type A from C. botulinum type C in reference laboratories was based on 16S rDNA sequence data and specific neutralisation of cytopathic effects in tissue culture.

Isolation and identification of clostridia from the intestine of laboratory animals

Quantitative and qualitative examination of faecal clostridia from laboratory mice, rats, hamsters and rabbits was carried out by using selective as well as nonselective culture techniques. The 364 isolates were identified where possible, to species level on the basis of physiological and biochemical characteristics. Most isolates from mice and rabbits were identified, i.e. 79.4% and 76.5%, respectively, while only 25.4% and 28.6% of isolates from rats and hamsters were characterized as described species. The most common species of the 16 identified were: C. coccoides, C. cocleatum and C. innocuum from mice; C. cocleatum, C. cochlearium and C. irregularis from rats; C. cocleatum and C. irregularis from hamsters; and C. aminovalericum and C. irregularis from rabbits. Unidentified Clostridium spp. were isolated from each animal species tested and were tentatively classified into 26 groups. None of these groups was found in more than one animal species in this study.

Rapid identification ofClostridium difficile by determination of leucine arylamidase activity

Rapid identification ofClostridium difficile by determination of leucine arylamidase activity

Identification of Clostridium difficile using the API ZYM system.

The use of the API ZYM system for the identification of Clostridium difficile was investigated. The enzyme profiles generated by this system readily distinguished strains of Clostridium difficile from other clostridia commonly isolated from faeces. Enzyme activity of Clostridium difficile was influenced by the composition of the culture medium but appeared to be independent of the age of the culture. Given careful standardisation of techniques the API ZYM system is a suitable alternative to conventional techniques for identification of Clostridium difficile.

Identification ofClostridium difficile by detection of p-cresol in a cooked meat medium

Identification ofClostridium difficile by detection of p-cresol in a cooked meat medium

Isolation and identification of clostridia from North Sea sediments.

SummaryUsing enrichment techniques, it was possible to isolate clostridia from marine sediments collected from 10 stations in the North Sea. Of the total number of isolates Clostridium bifermentans constituted 47% and Cl. welchii 21%, while Cl. sordellii constituted 18%. The remainder were unknown species. Evidence of cellulolysis was obtained, but no organism has as yet been isolated. No psychrophilic anaerobes were found.

COMPARISON OF MEDIA FOR THE ISOLATION OF CLOSTRIDIUM PERFRINGENS FROM FOOD. , ,

SummaryThe purpose of the study was to determine how SPS agar of Angelotti et al. (2) compared with certain other solid media proposed for the isolation or identification of clostridia. An attempt was made, therefore, to recover viable cells of three strains of Clostridium perfringens from various suspending media using five plating media. The results were analyzed statistically.The results may be summarized by stating that in every case SPS agar proved to be better than the other media examined for the recovery of the organisms; and that neither the food constituents tested nor mixed cultures of organisms affected the quantitative recovery of C. perfringens. The presence of sulfadiazine and polymyxin-B-sulfate in the medium did not affect the recovery of C. perfringens in a statistically significant manner.

Some new media for the isolation and identification of Clostridia.

Some new media for the isolation and identification of Clostridia.

A medium for the identification of clostridia producing opalescence in egg‐yolk emulsions

A medium for the identification of clostridia producing opalescence in egg‐yolk emulsions

The Isolation and Identification of Clostridia in the Field

The Isolation and Identification of Clostridia in the Field