The short time antibacterial effect of tetracaine hydrochloride was studied. S. aureus, Coagulase Negative Staphylococcus and P. aeruginosa were each incubated with tetracaine hydrochloride(preservative free) for 18 hours or for 2 minutes and then diluted and cultured on nutrient agar plate. Colony counts were done after 18 hours. In cases of 18 hours incubation, there was no growth of microbials in 0.5%, 0.1% tetracaine hydrochloride, but there was no inhibitory effect of 0.02% of tetracaine hydrochloride on growth of microbials, irrespective of inoculum amount. In cases of 2 minutes incubation with 0.5% tetracaine hydrochloride, there was no difference between the amount of microbial inoculum and colony count. Above in vitro study indicates that tetracaine hydrochloride has no inhibitory effect on bacterial growth in short time exposure less than 2 minutes.
Agar ; Coagulase ; Staphylococcus ; Tetracaine*

The short time antibacterial effect of tetracaine hydrochloride was studied. S. aureus, Coagulase Negative Staphylococcus and P. aeruginosa were each incubated with tetracaine hydrochloride(preservative free) for 18 hours or for 2 minutes and then diluted and cultured on nutrient agar plate. Colony counts were done after 18 hours. In cases of 18 hours incubation, there was no growth of microbials in 0.5%, 0.1% tetracaine hydrochloride, but there was no inhibitory effect of 0.02% of tetracaine hydrochloride on growth of microbials, irrespective of inoculum amount. In cases of 2 minutes incubation with 0.5% tetracaine hydrochloride, there was no difference between the amount of microbial inoculum and colony count. Above in vitro study indicates that tetracaine hydrochloride has no inhibitory effect on bacterial growth in short time exposure less than 2 minutes.
Agar ; Coagulase ; Staphylococcus ; Tetracaine*

KOH examination is a simple, rapid and diagnostic procedure to confirm dermatophytic infections. It is important to select a proper examination site of the lesion. To determinate the proper examination site of the lesion, mycologic studies were done with multiple specimens collected from the center, margin and out of margin of the ring-shaped dermatophytic skin lesion on the 58 patients. The results were as follows. Positive rate of KOH wet smear was 94.8% at the center and 100% at the margin of the lesions, 22.4% at the 1 cm and 5.2% at the 2 cm out of the lesions. The more hyphae were found in the lesion, the more hyphae were found out of the lesion. Culture was done on the Sabouraud's glucose agar from the highest KOH positive area and the positive culture was 48 strains (82.8%) of 58 patients. These findings suggested that the ring-shaped active margin was the best site to examine mycologic studies.
Agar ; Glucose ; Humans ; Hyphae ; Skin*

BACKGROUND: Early and appropriate antibiotic treatment improves the clinical outcome of patients with septicemia; therefore, reducing the turn-around time for identification (ID) and antimicrobial susceptibility test (AST) results is essential. We established a method for rapid ID and AST using short-term incubation of positive blood culture broth samples on solid media, and evaluated its performance relative to that of the conventional method using two rapid ID systems and a rapid AST method. METHODS: A total of 254 mono-microbial samples were included. Positive blood culture samples were incubated on blood agar plates for six hours and identified by the MicroFlex LT (Bruker Daltonics) and Vitek-MS (bioMeriéux) systems, followed by AST using the Vitek2 System (bioMeriéux). RESULTS: The correct species-level ID rates were 82.3% (209/254) and 78.3% (199/254) for the MicroFlex LT and Vitek-MS platforms, respectively. For the 1,174 microorganism/antimicrobial agent combinations tested, the rapid AST method showed total concordance of 97.8% (1,148/1,174) with the conventional method, with a very major error rate of 0.5%, major error rate of 0.7%, and minor error rate of 1.0%. CONCLUSIONS: Routine implementation of this short-term incubation method could provide ID results on the day of blood culture-positivity detection and one day earlier than the conventional AST method. This simple method will be very useful for rapid ID and AST of bacteria from positive blood culture bottles in routine clinical practice.
Agar ; Bacteria* ; Humans ; Methods ; Sepsis

BACKGROUND: The aim of this study is to evaluate the effectiveness of automated ozonated water endoscopic reprocessing system (AORS). MATERIALS AND METHODS: Thirty cases were collected and randomly assigned to 3 groups according to the disinfection methods (Group A, AORS for 5 minutes; Group B, AORS for 10 minutes; Group C, automated disinfection with superoxidized water for 3 minutes 30 seconds). After disinfection was finished, samples were collected from the tip of scopes (Site 1, S1) and rinsing water through biopsy channel (Site 2, S2). Samples were inoculated in blood agar plate for 48 hrs, and then colony count was evaluated. RESULTS: Culture positive rate of S1 was 0% in all three groups. Culture positive rates of S2 were 70% (7/10), 70% (7/10) and 90% (9/10) in group A, group B and group C, respectively. High culture rate group (> or = 1 CFU/ml rinsing water) was 0% (0/10), 30% (3/10) and 70% (7/10) in group A, group B and group C, respectively. Disinfection efficacy between group A and C showed a significant difference in high culture rate (P<0.05). CONCLUSIONS: AORS for 5min was at least equally effective in endoscopic reprocessing compared with the conventional superoxidized water system.
Agar ; Biopsy ; Disinfection* ; Endoscopes ; Water*

BACKGROUND: The aim of this study is to evaluate the effectiveness of automated ozonated water endoscopic reprocessing system (AORS). MATERIALS AND METHODS: Thirty cases were collected and randomly assigned to 3 groups according to the disinfection methods (Group A, AORS for 5 minutes; Group B, AORS for 10 minutes; Group C, automated disinfection with superoxidized water for 3 minutes 30 seconds). After disinfection was finished, samples were collected from the tip of scopes (Site 1, S1) and rinsing water through biopsy channel (Site 2, S2). Samples were inoculated in blood agar plate for 48 hrs, and then colony count was evaluated. RESULTS: Culture positive rate of S1 was 0% in all three groups. Culture positive rates of S2 were 70% (7/10), 70% (7/10) and 90% (9/10) in group A, group B and group C, respectively. High culture rate group (> or = 1 CFU/ml rinsing water) was 0% (0/10), 30% (3/10) and 70% (7/10) in group A, group B and group C, respectively. Disinfection efficacy between group A and C showed a significant difference in high culture rate (P<0.05). CONCLUSIONS: AORS for 5min was at least equally effective in endoscopic reprocessing compared with the conventional superoxidized water system.
Agar ; Biopsy ; Disinfection* ; Endoscopes ; Water*

BACKGROUND: Stool culture for enteric pathogens constitutes a significant portion of the workload in clinical microbiology. Several reports recommended that selenite enrichment have been used only in stool cultures from suspected carriers, during outbreaks, and other special circumstances for cost-effectiveness. We evaluated the usefulness of selenite F enrichment for the isolation of Salmonella in routine stool cultures. METHODS: Stool specimens submitted from March to October, 1999 were inoculated onto MacConkey(Mac) agar and Salmonella-Shiegella(SS) agar and into Selenite F(SF) enrichment broth. After overnight incubation, the SF broth was subcultured onto a second SS agar. RESULTS: Total 45 strains of Salmonella spp. were recovered from 1,338 stool specimens and Shiegella or other enteric pathogens were not recovered. Twenty out of the forty-five Salmonella spp.(44%) were recovered on Mac agar and 33 of 45 Salmonella spp.(73%) on SS agar, 45 out of 45 Salmonella spp.(100%) after SF enrichment and 35 of 45 Salmonella spp.(78%) on Mac and/or SS agar. Ten Salmonella spp. were recovered only after SF enrichment, but no Salmonella spp. were recovered only on the primary Mac agar or SS agar. After SF enrichment, Salmonella spp. grew more purely and heavily than on the primary medium. CONCLUSIONS: These results suggest that SF enrichment is necessary to routine stool cultures and the elimination of the primary Mac or SS agar is cost-effective than the elimination of SF enrichment.
Agar ; Disease Outbreaks ; Salmonella* ; Selenious Acid*

BACKGROUND: During the specimen preparation, neutralization after alkali processing is not necessary when inoculate into agar or broth media, but into 3% Ogawa media, the mostly used egg-based media in Korea. To simplify the specimen processing, the recovery of mycobacteria from 3% Ogawa media inoculating differently processed sputa, was evaluated. Futhermore, the recovery from the three different media was evaluated, too. METHODS: 209 sputa were included. Each specimen was divided into 3 bottles.(A) One was only decontaminated by 4% NaOH before inoculation.(B) Another was decontaminated, and concentrated without neutralization. These two specimens were inoculated into 3% Ogawa media.(C) The other was decontaminated, neutralized and concentrated, and innoculated into 3% Ogawa, Middlebrook 7H9 selective broth and 7H10 selective agar media. The isolates were identified by AccuProbe method. RESULTS: M. tuberculosis were isolated from 43(20.5%) specimens. The recovery number and time from Ogawa media, inoculating specimens processed by A, B, and C method, were 29(13.9%), 35(16.7%), and 36(17.2%), and 23, 23, and 19 days, respectively. The recovery number and time from Ogawa, 7H10 agar and 7H9 broth media, inoculating specimens processed by C method, were 36(17.2%), 42(20.1%), and 41(19.6%), and 26, 24, and 22 days, respectively. CONCLUSIONS: Neutralization of alkali-decontaminated specimens could be used to inoculate into 3% Ogawa media. Inoculation into homemade 7H10 agar and 7H9 broth media in addition to 3% Ogawa media improved the recovery rate and time of mycobacteria.
Agar ; Alkalies ; Korea ; Mycobacterium tuberculosis ; Sputum ; Tuberculosis

BACKGROUND: Clostridium difficile is the main etiologic agent of antibiotic-associated diarrhea and the most common cause of hospital-acquired diarrhea. Recently, the incidence of C. difficile infections (CDI) has increased and new highly virulent C. difficile strains have emerged. Therefore, accurate and rapid diagnosis is needed. We compared the results of using chromID C. difficile (chromID CD, bioMerieux, France) with the conventional C. difficile Selective Agar (CDSA; BD, USA) for the isolation of C. difficile. METHODS: A total of 738 stool specimens of suspected CDI patients at the Severance Hospital from July to August 2011 were inoculated onto CDSA. Among them, 104 stool specimens revealed colonies on CDSA that were then re-inoculated onto chromID CD. The stool samples were stored at -20degrees C until the time of the re-inoculation. Cultured agars were interpreted after 24 hrs and 48 hrs, respectively. Species identification was performed on the basis of colony characteristics on agar plates as well as the ATB 32A system (API System SA, France). RESULTS: The recovery rates of CDSA and chromID CD were 30.1% and 77.5% after 24 hrs, and 77.5% and 98.6% after 48 hrs, respectively. All of the C. difficile isolates were recovered as typical gray/black colonies on chromID CD. CONCLUSION: The performance of chromID CD for the isolation of C. difficile was better than that of conventional CDSA. The chromID CD could provide easy and sensitive detection of C. difficile even after 24hrs of incubation.
Agar ; Clostridium ; Clostridium difficile ; Diarrhea ; Humans ; Incidence

BACKGROUND: Urine samples should be tested in a rapid and cost-effective way, as they represent the largest volume of specimens cultured in the microbiology laboratory. Some bacteria can be presumptively identified with CHROMagar Orientation (CO) according to the specific colors produced on the colonies. In this study, the usefulness of CO agar was evaluated for urine cultures. METHODS: The urine samples from 980 patients from March through April, 2004 were inoculated on blood agar (BAP), MacConkey agar, and CO agar plates, and we compared the detection rates of potential pathogens and the agreement between presumptive identification directly from the CO agar and the confirmative idntification, which was performed using Vitek systems (bioMerieux). RESULTS: The detection rates of urinary tract pathogens on all three media, conventional BAP, MacConkey agar and CO agar were identical (18.9%). All isolates of Escherichia coli (54) and ente-rococci (40) were correctly identified with CO agar. The overall agreement of presumptive identification was 87.4% (187/199). CONCLUSIONS: Use of the CO agar enabled a rapid presumptive identification of E. coli, and ente-rococci, the most common urinary tract pathogens. The CO agar is cost-effective by saving some of the bacterial identification kits that would be required for the conventional BAP and MacConkey agar method.
Agar* ; Bacteria ; Escherichia coli ; Humans ; Urinary Tract*