Yong Jun Kwon, Seung A Byun, Min Ji Choi, Eun Jeong Won, Soo Hyun Kim, Jong Hee Shin
Ann Clin Microbiol 2019 December, 22(4): 81-89. Published on 20 December 2019.
Background: Candida auris was first isolated from the ears of Japanese and Korean patients. However, the prevalence of yeast isolates from ear cultures and their antifungal susceptibility profiles in these nations remain unclear.
Methods: We assessed yeast isolates recovered from ear cultures from a university hospital in Korea over a 4-year period from January 2014 to December 2017. Species identification was performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and/or sequence analysis. Antifungal minimal inhibitory concentrations (MICs) were determined using the broth microdilution method of the Clinical and Laboratory Standards Institute.
Results: Among 81 non-duplicate isolates from ear cultures, Cadida parapsilosis was the most frequently detected yeast species (34.6%), followed by C. auris (28.4%), Candida metapsilosis (9.9%), Candida orthopsilosis (8.6%), Candida albicans (7.4%), and others (11.1%). The MICs of the isolates were 0.125 to ＞64 μg/mL, ≤0.03 to 4 μg/mL, 0.25 to 1 μg/mL, 0.125 to 1 μg/mL, and ≤0.03 to 2 μg/mL for fluconazole, voriconazole, amphotericin B, caspofungin, and micafungin, respectively. Of the 81 isolates, 44.4% (36/81) showed decreased susceptibility to fluconazole (MIC ≥4 μg/mL). Of the 23 C. auris isolates, 19 (82.6%) had a fluconazole MIC of ≥32 μg/mL. None of the isolates showed resistance to amphotericin B or echinocandins. Most of these patients suffered from chronic otitis media (84%).
Conclusion: Candida parapsilosis complex and C. auris were the yeast species identified most frequently from ear cultures and they exhibited a high rate of fluconazole non-susceptibility, particularly C. auris.
[in Korean]
Min-Seung Park, In Young Yoo, On-Kyun Kang, Jung Eun Lee, Dae Joong Kim, Hee Jae Huh, Nam Yong Lee
Ann Clin Microbiol 2019 December, 22(4): 90-95. Published on 20 December 2019.
Background: A major complication of peritoneal dialysis (PD) is peritonitis, and bacterial culture of PD effluent in a blood culture bottle is the preferred technique for diagnosis of peritonitis. In this study, we compared dialysate inoculation and culture using the BacT/AlerTⓇ Fastidious Antimicrobial Neutralization Plus blood culture bottles (FAN Plus; bioMérieux, France) to the conventional centrifugation culture method.
Methods: A total of 170 PD effluents were simultaneously processed by the conventional centrifugation culture method and by culture using FAN Plus media with two different inoculation procedures: inoculation after centrifugation and direct bedside inoculation.
Results: Of the 52 cultures that were positive on at least one of the culture methods, 27 samples were positive on conventional centrifugation. However, 46 samples showed growth following inoculation into the FAN Plus media after centrifugation, and 47 samples were positive on the direct FAN Plus inoculation method. Using the case definition for PD peritonitis to classify samples, sensitivity of the conventional method was 50.0% (95% CI, 33.7-66.3%), whereas the sensitivity of the FAN Plus media was 78.9% (95% CI, 62.2-89.9%) by inoculation after centrifugation and 86.8% (95% CI, 71.1-95.1%) by direct inoculation. Use of both inoculation methods with FAN Plus media resulted in 92.1% sensitivity (95% CI, 89.2-99.9%).
Conclusion: Culture using FAN Plus media demonstrated a superior bacterial recovery rate to the conventional centrifugation culture method. A combination of the two inoculation methods with FAN Plus media is recommended for the best diagnostic yield, while direct inoculation alone can be useful due to its simplicity and cost-effectiveness.
Seon Han Yun, Bareum Gwon, Hea Lim Hong, Hwan Seop Lim, Kyung Ryul Lee, Inho Jang, Eun-Jeong Yoon, Seok Hoon Jeong
Ann Clin Microbiol 2019 December, 22(4): 96-104. Published on 20 December 2019.
Background: Antimicrobial resistance (AMR) is an issue not only with regard to public health, but also in terms of economic impact. AMR surveillance has mainly been carried out in general hospitals, and not in nursing hospitals. This study was conducted to investigate the AMR rate for bacterial strains isolated from nursing hospital samples.
Methods: Antimicrobial susceptibility testing (AST) results from a total of 23,518 bacterial isolates recovered from clinical specimens taken in 61 nursing hosals were analyzed. AST was conducted using Vitek 2 with AST cards specific for the bacterial strains.
Results: A total of 19,357 Gram-negative and 4,161 Gram-positive bacterial strains were isolated. Pseudomonas aeruginosa (n=6,384) and Escherichia coli (n= 5,468) were the most prevalent bacterial species and, among Gram-positive bacteria, Staphylococcus aureus (n=1,565) was common. The AMR rate was high for the following strains: cefotaxime-resistant Klebsiella pneumoniae, 77.4%; cefotaxime-resistant E. coli, 70.6%; imipenem-resistant Acinetobacter baumannii, 90.3%; imipenem-resistant P. aeruginosa, 49.3%; oxacillin-resistant S. aureus, 81.1%, penicillin-resistant Enterococcus faecalis, 44.8%, and vancomycin-resistant Enterococcus faecium, 53.5%. AMR rate change varied by bacterial species and antimicrobial drug.
Conclusion: AMR rates of major pathogens from nursing hospitals were higher than those from general hospitals with the exception of imipenem-resistant A. baumannii. Continuous monitoring and infection control strategies are needed.
[in Korean]
Young Jin Ko, Soo-Young Yoon, Chae Seung Lim, Chang Kyu Lee
Ann Clin Microbiol 2019 December, 22(4): 105-109. Published on 20 December 2019.
We report a case of cellulitis caused by a novel Cupriavidus species identified using whole-genome sequence analysis. Subcutaneous tissue biopsies from the left lower leg of a 67-year-old man who suffered from cellulitis were cultured. Round, convex, gray and non-hemolytic colonies were recovered after 72-h incubation. 16S rRNA sequence analysis showed 98.6% similarity with Cupriavidus basilensis DSM 11853(T) in the NCBI database and 99.9% similarity with C. basilensis KF708 in the EzBioCloud database. Genomic analysis using the MiSeq platform (Illumina, USA) and the TrueBac ID database (ChunLab, Korea) revealed that the average nucleotide identity (ANI) of this strain with C. basilensis DSM 11853(T) was 87.6%. The patient was treated with oral cefditoren pivoxil for 9 weeks. This study is the first to report cellulitis caused by Cupriavidus species strain J1218. (Ann Clin Microbiol 2019;22:105-109)
