Prototheca wickerhamii is an achlorophyllic algae that rarely acts as an opportunistic pathogen in humans. We report the case of a 66-year-old female patient with a history of diabetes mellitus who presented with a pus-like discharge from face, facial redness, and swelling. The patient was admitted to the emergency room with worsening facial pain. Gram staining from pus-like discharge revealed yeast like features; however, an isolated colony on a blood agar plate was not identified using VITEK 2 (Biomerieux) or matrix-assisted laser desorption/ionization time-of flight mass spectrometry (MALDI-TOF) using VITEK MS (Biomerieux). Lactophenol cotton blue staining of the colony revealed characteristic sporangia and endospore features. After performing the protein extraction procedure for filamentous fungi (mold) isolates using ethanol and formic acid, MALDI-TOF MS identified the colony as Prototheca wickerhamii, with 99.9% confidence. This case indicates that Prototheca spp.require specialized sample preparation steps, such as the ethanol/formic acid extraction procedure, for identification using MALDI-TOF MS.

Prototheca wickerhamii is an achlorophyllic algae that rarely acts as an opportunistic pathogen in humans. We report the case of a 66-year-old female patient with a history of diabetes mellitus who presented with a pus-like discharge from face, facial redness, and swelling. The patient was admitted to the emergency room with worsening facial pain. Gram staining from pus-like discharge revealed yeast like features; however, an isolated colony on a blood agar plate was not identified using VITEK 2 (Biomerieux) or matrix-assisted laser desorption/ionization time-of flight mass spectrometry (MALDI-TOF) using VITEK MS (Biomerieux). Lactophenol cotton blue staining of the colony revealed characteristic sporangia and endospore features. After performing the protein extraction procedure for filamentous fungi (mold) isolates using ethanol and formic acid, MALDI-TOF MS identified the colony as Prototheca wickerhamii, with 99.9% confidence. This case indicates that Prototheca spp.require specialized sample preparation steps, such as the ethanol/formic acid extraction procedure, for identification using MALDI-TOF MS.

Prototheca wickerhamii is an achlorophyllic algae that rarely acts as an opportunistic pathogen in humans. We report the case of a 66-year-old female patient with a history of diabetes mellitus who presented with a pus-like discharge from face, facial redness, and swelling. The patient was admitted to the emergency room with worsening facial pain. Gram staining from pus-like discharge revealed yeast like features; however, an isolated colony on a blood agar plate was not identified using VITEK 2 (Biomerieux) or matrix-assisted laser desorption/ionization time-of flight mass spectrometry (MALDI-TOF) using VITEK MS (Biomerieux). Lactophenol cotton blue staining of the colony revealed characteristic sporangia and endospore features. After performing the protein extraction procedure for filamentous fungi (mold) isolates using ethanol and formic acid, MALDI-TOF MS identified the colony as Prototheca wickerhamii, with 99.9% confidence. This case indicates that Prototheca spp.require specialized sample preparation steps, such as the ethanol/formic acid extraction procedure, for identification using MALDI-TOF MS.

Prototheca wickerhamii is an achlorophyllic algae that rarely acts as an opportunistic pathogen in humans. We report the case of a 66-year-old female patient with a history of diabetes mellitus who presented with a pus-like discharge from face, facial redness, and swelling. The patient was admitted to the emergency room with worsening facial pain. Gram staining from pus-like discharge revealed yeast like features; however, an isolated colony on a blood agar plate was not identified using VITEK 2 (Biomerieux) or matrix-assisted laser desorption/ionization time-of flight mass spectrometry (MALDI-TOF) using VITEK MS (Biomerieux). Lactophenol cotton blue staining of the colony revealed characteristic sporangia and endospore features. After performing the protein extraction procedure for filamentous fungi (mold) isolates using ethanol and formic acid, MALDI-TOF MS identified the colony as Prototheca wickerhamii, with 99.9% confidence. This case indicates that Prototheca spp.require specialized sample preparation steps, such as the ethanol/formic acid extraction procedure, for identification using MALDI-TOF MS.

Prototheca wickerhamii is an achlorophyllic algae that rarely acts as an opportunistic pathogen in humans. We report the case of a 66-year-old female patient with a history of diabetes mellitus who presented with a pus-like discharge from face, facial redness, and swelling. The patient was admitted to the emergency room with worsening facial pain. Gram staining from pus-like discharge revealed yeast like features; however, an isolated colony on a blood agar plate was not identified using VITEK 2 (Biomerieux) or matrix-assisted laser desorption/ionization time-of flight mass spectrometry (MALDI-TOF) using VITEK MS (Biomerieux). Lactophenol cotton blue staining of the colony revealed characteristic sporangia and endospore features. After performing the protein extraction procedure for filamentous fungi (mold) isolates using ethanol and formic acid, MALDI-TOF MS identified the colony as Prototheca wickerhamii, with 99.9% confidence. This case indicates that Prototheca spp.require specialized sample preparation steps, such as the ethanol/formic acid extraction procedure, for identification using MALDI-TOF MS.

Acquired fluconazole resistance (FR) in bloodstream infection (BSI) isolates of Candida albicans is rare. We investigated the FR mechanisms and clinical features of 14 fluconazole non-susceptible (FNS; FR and fluconazole-susceptible dose-dependent) BSI isolates of C. albicans recovered from Korean multicenter surveillance studies during 2006–2021. Mutations causing amino acid substitutions (AASs) in the drug-target gene ERG11 and the FR-associated transcription factor genes TAC1 , MRR1, and UPC2 of the 14 FNS isolates were compared with those of 12 fluconazole-susceptible isolates. Of the 14 FNS isolates, eight and seven had Erg11p (K143R, F145L, or G464S) and Tac1p (T225A, R673L, A736T, or A736V) AASs, respectively, which were previously described in FR isolates. Novel Erg11p, Tac1p, and Mrr1p AASs were observed in two, four, and one FNS isolates, respectively. Combined Erg11p and Tac1p AASs were observed in seven FNS isolates. None of the FR-associated Upc2p AASs were detected. Of the 14 patients, only one had previous azole exposure, and the 30-day mortality rate was 57.1% (8/14). Our data show that Erg11p and Tac1p AASs are likely to contribute to FR in C. albicans BSI isolates in Korea and that most FNS C. albicans BSIs develop without azole exposure.

Background: Rapid detection of the causative agents is essential for determining the appropriate treatment for patients with lower respiratory tract infections. We evaluated the performance of the Biofire FilmArray pneumonia panel (FA-PE; BioFire Diagnostics, USA) in the identification of bacterial pathogens and antibiotic resistance genes in endotracheal aspirate specimens. Methods: A total of 43 non-duplicated endotracheal aspirates were included in this study. The performance of the FA-PE was assessed using the routine culture method as the reference standard. Results: The FA-PE demonstrated 92.9% sensitivity and 79.3% specificity for the identification of 15 bacterial targets compared to routine bacterial culture. Four antimicrobial resistance genes in 43 specimens were detected by the FA-PE. The most frequently detected resistance genes were mecA/C and SCCmec in three specimens, followed by CTX-M in one specimen. Conclusion The FA-PE offers a rapid diagnostic method for lower respiratory tract infections.It may be useful at the early stage of pneumonia, before routine culture and antimicrobial susceptibility results are available.

Background: Liquid biopsy is a useful assay for the diagnosis, treatment, and prognosis prediction of solid tumors and its clinical application is expanding. Therefore, the need for developing an External Quality Assessment (EQA) protocol for liquid biopsy is increasing. In this study, we developed and implemented the liquid biopsy EQA program for the epidermal growth factor receptor mutation. Methods: We validated the feasibility of the protocol using citrate instead of ethylenediaminetetraacetic acid (EDTA). Additionally, we analyzed the homogeneity and stability of the aliquoted quality control (QC) materials. Mutation-positive QC material with four mutations (exon 19 deletion, L858R, T790M, and exon 20 insertion) was used to make two types of QC materials (low and high) and the wild type material was used for the negative controls. If the EQA results showed consensus in more than 80% of the participating laboratories, the results were reported as acceptable or unacceptable. If not, we reported the results as not graded. Results: Citrate showed equivalent performance to EDTA. Highly mutated QC material and mutation-negative QC material passed the homogeneity and stability test, but low-level mutant specimens showed inconsistent results. In total, 11 laboratories participated, and all of them reported consistent results except for low-grade mutant samples. Thus, the evaluation results were acceptable except for low mutation QC material. Conclusions The applicability of liquid biopsy is expanding. To obtain accurate test results, EQA is indispensable. Here, QC materials for liquid biopsy EQA were produced, distributed, and had its results analyzed. This study could be the foundation for further development of liquid biopsy EQA.

BACKGROUND: Without standardization of medical laboratory's testing practices, there is an increase in false diagnoses when relying on test results. However, the effect of test standardization is difficult to assess numerically. This study's purpose is to quantify the effect of the standardization level of a laboratory on the prevalence of diabetes mellitus (DM) and impaired fasting glucose (IFG). METHODS: Laboratories were classified into three levels: ‘highly-standardized laboratory,’‘basically-standardized laboratory,’ and ‘non-standardized laboratory.’ Based on the results of Korean External Quality Assessment Scheme (KEQAS), the cutoff values for diagnosis of DM and IFG were recalculated, given false positive and false negative rates. RESULTS: The prevalence of DM and IFG in the population as a whole was estimated using the 2013 Korea National Health and Nutrition Examination Survey (KNHANES) database. When the prevalence of DM from KNHANES was 11.88% (95% confidence interval [CI], 10.59%–13.17%), the proportion with a systematic false error ranged from 10.91% (95% CI, 9.65%–12.17%) to 13.09% (95% CI, 11.74%–14.45%). The prevalence of IFG varied from 13.59% (95% CI, 12.25%–14.91%) to 40.49% (95% CI, 38.54%–42.43%), in contrast to 24.58% (95% CI, 22.85%–26.31%) of the reference value. The prevalence of DM and IFG tended to be over- and under-estimated more as the laboratory standardization level became lower, respectively. CONCLUSION: Our study proved that standardization of clinical laboratory tests is an important factor affecting the prevalence estimation of national disease statistics based on the simulation using KNHANES data.
Diabetes Mellitus* ; Diagnosis ; Diagnostic Tests, Routine* ; Fasting* ; Glucose* ; Korea ; Nutrition Surveys ; Prevalence* ; Reference Values

The period of study in title should have been listed as ‘in the Past Nine Years’. Therefore, we ask to correct ‘from 2015 to 2017’ with ‘from 2007 to 2015’.