At the time when owing to COVID-19 pandemic, the public is more interested in infectious diseases and pathogens than in any other period, a book titled “The New Microbiology: From Microbiomes to CRISPR” by the renowned microbiologist Pascale Cossart was translated and published by our colleague. In this book, the author describes important discoveries and new conceptual advances in the field of microbiology over the past century. The author emphasizes that bacteria form a microbiome and lead a social life and explains the impact and importance of the microbiome on human health and ecosystem. Further, the discovery of ‘CRISPR,’ which led to the era of genome editing and gene therapy, has been described in details. This book will dramatically change our perspective regarding all living things, including bacteria, plants, animals, and even insects, as well as our eating habits and daily life, based on the new understanding of microorganisms. I recommend reading this book as I am sure that it will broaden the perspectives of both clinical microbiologists and health care workers.

BACKGROUND: We aimed to validate a pilot study of photodiagnosis using near infrared (NIR) transillumination and assess the clinical efficacy of hypericin-mediated photodynamic therapy (HYP-PDT) in a rabbit laryngeal cancer model in order to develop a novel therapeutic modality with complete remission and preservation of the functional organ. METHODS: (1) In vitro study: VX tumor cells were subcultured and subjected to HYP-PDT. (2) In vivo study: A laryngeal cancer model was developed in which 12 rabbits were inoculated with a VX tumor suspension in the submucosal area of the left vocal fold using a transoral approach. All rabbits underwent NIR transillumination using light with a wavelength of 780 nm. The survival periods of the three treatment groups (6 rabbits in Group A: HYP-PDT, 3 each in Groups B and C: laser irradiation or HYP administration only) were analyzed. RESULTS: The higher the HYP concentration, the lower the VX cell viability in response to HYP-PDT using 590 nm LED. Following HYP-PDT, small tumors in Group A-1 rabbits healed completely and the animals demonstrated a long survival period, and larger tumors in Group A-2 healed partially with a survival period that extended over 3 weeks after inoculation. The survival of Groups B and C were not different over the first 3 weeks of the study, and were shorter than in Group A. CONCLUSION We found HYP-PDT could be a curative therapy for early-stage cancers that may also preserve organ function, and may inhibit tumor progression and metastasis during advanced stages of laryngeal cancer.

BACKGROUND: Nasopharyngeal aspirate (NPA) is known as the best specimen for accurate diagnosis of viral respiratory infections in pediatric patients, but the procedure is very annoying. Recently introduced flocked swabs have been reported to be easy to obtain a good quality specimen and comfortable to patients. The purpose of this study was to compare the sensitivities between NPA and nasopharyngeal flocked swabs (NPFS) for detection of respiratory viruses in children. METHODS: For this study, 111 hospitalized children with acute respiratory tract infections were recruited. NPA and NPFS were performed in parallel from each patient. NPFS were always collected after NPA. Specimens were tested for six common respiratory viruses in triplicate using indirect immunofluorescence (IIF), viral cultures, and multiplex reverse transcription PCR (RT-PCR). RESULTS: The proportion of specimens inadequate for IIF was higher in NPA (23.4%) than NPFS (5.4%). According to the consensus positive, the positive rates of NPFS were higher than those of NPA when using IIF (45.7% and 30.6%, P=0.048) and culture (38.7% and 27.9%, P=0.004). However, the false-positive rates of NPFS were higher than those of NPA when using IIF (12.4% and 1.2%, P=0.004). The positive rates of NPFS and those of NPA were not different in multiplex RT-PCR (67.6% and 55.9%, P=0.055). CONCLUSION: The higher sensitivity of IIF for NPFS specimens and of culture for respiratory viruses and the similar sensitivities in multiplex PCR could make them an alternative to NPA samples, especially in physician clinics or emergency rooms.
Child ; Child, Hospitalized ; Consensus ; Diagnosis ; Emergency Service, Hospital ; Fluorescent Antibody Technique, Indirect ; Humans ; Multiplex Polymerase Chain Reaction ; Nasopharynx ; Polymerase Chain Reaction ; Respiratory Tract Infections ; Reverse Transcription ; Specimen Handling

PURPOSE: This study investigated the clinical presentations of symptomatic Clostridium difficile infection (CDI) in children. METHODS: We reviewed the medical records of 43 children aged <20 years who showed either positive C. difficile culture or C. difficile toxin test results between June 2010 and April 2014. RESULTS: Of the 43 patients (mean age 6.7 years), 22 were boys. Sixteen patients (37.2%) showed both positive C. difficile culture and toxin test results. Seventeen out of 43 children (39.5%) had preexisting gastrointestinal diseases, and 26 children had other medical conditions that were risk factors for CDI. Twenty-eight children had a history of antibiotic treatment for >3 days, and the most frequently prescribed antibiotic was amoxicillin-clavulanate (35.7%). Twenty-eight patients were diagnosed with CDI despite taking probiotic supplements, most commonly Lactobacillus acidophilus (53.6%). The most common symptom was diarrhea (72.1%) at the time CDI was diagnosed. C. difficile was eradicated in 11 patients (25.6%) after treatment with oral metronidazole for 10-14 days, and in the two patients (4.6%) who required two courses of oral metronidazole. Sixteen patients (37.2%) showed clinical improvement without any treatment. CONCLUSION: This study showed the various clinical characteristics of CDI in children and that preexisting clinical conditions favored the development of CDI. In addition, CDI was found to occur in a number of patients even after probiotic prophylaxis given in conjunction with antibiotic therapy.
Child* ; Clostridium difficile* ; Diarrhea ; Gastrointestinal Diseases ; Humans ; Lactobacillus acidophilus ; Medical Records ; Metronidazole ; Probiotics* ; Risk Factors

With increase of multi-drug resistant Escherichia coli in community-acquired urinary tract infections (CA-UTI), other treatment option with a therapeutic efficacy and a low antibiotic selective pressure is necessary. In this study, we evaluated in vitro susceptibility of E. coli isolates from CA-UTI to fosfomycin (FM), nitrofurantoin (NI), temocillin (TMO) as well as trimethoprim-sulfamethoxazole (SMX), ciprofloxacin (CIP) and cefepime (FEP). The minimal inhibitory concentrations were determined by E-test or agar dilution method according to the Clinical and Laboratory Standards Institute guidelines, using 346 E. coli collected in 12 Korean hospitals from March 2010 to February 2011. FM, NI and TMO showed an excellent susceptibility profile; FM 100% (346/346), TMO 96.8% (335/346), and NI 99.4% (344/346). Conversely, resistance rates of CIP and SMX were 22% (76/346) and 29.2% (101/349), respectively. FEP still retained an activity of 98.5%. In Korea, NI and TMO in addition to FM are a good therapeutic option for uncomplicated CA-UTI, especially for lower UTI.
Anti-Bacterial Agents/*administration & dosage ; Cell Survival/*drug effects ; Cephalosporins/administration & dosage ; Ciprofloxacin/administration & dosage ; Community-Acquired Infections/drug therapy/*microbiology ; Dose-Response Relationship, Drug ; Drug Combinations ; Drug Resistance, Bacterial/drug effects ; Escherichia coli/*drug effects ; Escherichia coli Infections/drug therapy/*microbiology ; Fosfomycin/administration & dosage ; Humans ; Nitrofurantoin/administration & dosage ; Penicillins/administration & dosage ; Republic of Korea ; Sulfadoxine/administration & dosage ; Treatment Outcome ; Trimethoprim/administration & dosage ; Urinary Tract Infections/diagnosis/*microbiology

With increase of multi-drug resistant Escherichia coli in community-acquired urinary tract infections (CA-UTI), other treatment option with a therapeutic efficacy and a low antibiotic selective pressure is necessary. In this study, we evaluated in vitro susceptibility of E. coli isolates from CA-UTI to fosfomycin (FM), nitrofurantoin (NI), temocillin (TMO) as well as trimethoprim-sulfamethoxazole (SMX), ciprofloxacin (CIP) and cefepime (FEP). The minimal inhibitory concentrations were determined by E-test or agar dilution method according to the Clinical and Laboratory Standards Institute guidelines, using 346 E. coli collected in 12 Korean hospitals from March 2010 to February 2011. FM, NI and TMO showed an excellent susceptibility profile; FM 100% (346/346), TMO 96.8% (335/346), and NI 99.4% (344/346). Conversely, resistance rates of CIP and SMX were 22% (76/346) and 29.2% (101/349), respectively. FEP still retained an activity of 98.5%. In Korea, NI and TMO in addition to FM are a good therapeutic option for uncomplicated CA-UTI, especially for lower UTI.
Anti-Bacterial Agents/*administration & dosage ; Cell Survival/*drug effects ; Cephalosporins/administration & dosage ; Ciprofloxacin/administration & dosage ; Community-Acquired Infections/drug therapy/*microbiology ; Dose-Response Relationship, Drug ; Drug Combinations ; Drug Resistance, Bacterial/drug effects ; Escherichia coli/*drug effects ; Escherichia coli Infections/drug therapy/*microbiology ; Fosfomycin/administration & dosage ; Humans ; Nitrofurantoin/administration & dosage ; Penicillins/administration & dosage ; Republic of Korea ; Sulfadoxine/administration & dosage ; Treatment Outcome ; Trimethoprim/administration & dosage ; Urinary Tract Infections/diagnosis/*microbiology

BACKGROUND: Antimicrobial susceptibility testing (AST) of Clostridium difficile is increasingly important because of the rise in resistant strains. The standard medium for the AST of C. difficile is supplemented Brucella agar (sBA), but we found that the growth of C. difficile on sBA was not optimal. Because active growth is critical for reliable AST, we developed a new, modified C. difficile (mCD) agar. C. difficile grew better on mCD agar than on sBA. METHODS: C. difficile isolates were collected from patients with healthcare-associated diarrhea. sBA medium was prepared according to the CLSI guidelines. Homemade mCD agar containing taurocholate, L-cysteine hydrochloride, and 7% horse blood was used. For 171 C. difficile isolates, we compared the agar dilution AST results from mCD agar with those from sBA. RESULTS: No significant differences were observed in the 50% minimal inhibitory concentration (MIC50) and 90% minimal inhibitory concentration (MIC90) of clindamycin (CLI), metronidazole (MTZ), moxifloxacin (MXF), piperacillin-tazobactam (PTZ), and rifaximin (RIX), but the values for vancomycin (VAN) were two-fold higher on mCD agar than on sBA. The MICs of CLI, MXF, and RIX were in 100% agreement within two-fold dilutions, but for MTZ, VAN, and PTZ, 13.7%, 0.6%, and 3.1% of the isolates, respectively, were outside the acceptable range. CONCLUSIONS: The MIC ranges, MIC50 and MIC90, were acceptable when AST was performed on mCD agar. Thus, mCD agar could be used as a substitute medium for the AST of C. difficile.
Anti-Infective Agents/*pharmacology ; Clostridium Infections/microbiology ; Clostridium difficile/*drug effects/isolation & purification ; Diarrhea/*microbiology ; Humans ; Microbial Sensitivity Tests/*methods

BACKGROUND: Binary toxin-producing Clostridium difficile infections (CDI) are known to be more severe and to cause higher case fatality rates than those by binary toxin-negative isolates. There has been few data of binary toxin-producing CDI in Korea. Objective of the study is to characterize clinical and microbiological trait of CDI cause by binary-toxin producing isolates in Korea. MATERIALS AND METHODS: From September 2008 through January 2010, clinical characteristics, medication history and treatment outcome of all the CDI patients were collected prospectively. Toxin characterization, PCR ribotyping and antibiotic susceptibility were performed with the stool isolates of C. difficile. RESULTS: During the period, CDI caused by 11binary toxin-producing isolates and 105 toxin A & toxin B-positive binary toxin-negative isolates were identified. Comparing the disease severity and clinical findings between two groups, leukocytosis and mucoid stool were more frequently observed in patients with binary toxin-positive isolates (OR: 5.2, 95% CI: 1.1 to 25.4, P = 0.043; OR: 7.6, 95% CI: 1.6 to 35.6, P = 0.010, respectively), but clinical outcome of 2 groups did not show any difference. For the risk factors for acquisition of binary toxin-positive isolates, previous use of glycopeptides was the significant risk factor (OR: 6.2, 95% CI: 1.4 to 28.6, P = 0.019), but use of probiotics worked as an inhibitory factor (OR: 0.1, 95% CI: 0.0 to 0.8; P = 0.026). PCR ribotypes of binary toxinproducing C. difficile showed variable patterns: ribotype 130, 4 isolates; 027, 3 isolates; 267 and 122, 1 each isolate and unidentified C1, 2 isolates. All 11 binary toxin-positive isolates were highly susceptible to clindamycin, moxifloxacin, metronidazole, vancomycin and piperacillin-tazobactam, however, 1 of 11 of the isolates was resistant to rifaximin. CONCLUSIONS: Binary toxin-producing C. difficile infection was not common in Korea and those isolates showed diverse PCR ribotypes with high susceptibility to antimicrobial agents. Glycopeptide use was a risk factor for CDI by those isolates.
Anti-Infective Agents ; Aza Compounds ; Clindamycin ; Clostridium ; Clostridium difficile ; Glycopeptides ; Humans ; Korea ; Leukocytosis ; Metronidazole ; Polymerase Chain Reaction ; Probiotics ; Prospective Studies ; Quinolines ; Ribotyping ; Risk Factors ; Sprains and Strains ; Treatment Outcome ; Vancomycin

Healthcare personnel (HCP) face a wide range of occupational hazards, including needle-stick injuries, back injuries, latex allergy, violence, and stress. In particular, occupational exposures to infectious agents, such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV),or tuberculosis, are devastating to the victims. The World Health Organization (WHO) estimates the global burden of disease from occupational exposure to be 40% of hepatitis B and C virus infections and 2.5% of the HIV infections among HCP. Infectious disease cases for which compensation is given by the Korean Occupational Safety and Health Agency are increasing, and tuberculosis is the most common infectious disease compensated by KOSHA for HCP in Korea. While viral respiratory infections are common in health care settings, systematic surveillance has not been established yet in Korea. Infection control programs for HCP, such as engineering control in medical facilities, immunization, post exposure prophylaxis, and use of personal protective equipment need to be improved in Korea. This article describes the epidemiologic characteristics of occupational infectious diseases among HCP in Korea, especially focusing on needle-stick injuries and airborne infections. Also brief commentary is offered concerning effective measures for the control and prevention of occupational infectious disease transmission among HCP.
Back Injuries ; Communicable Diseases ; Compensation and Redress ; Delivery of Health Care ; Disease Transmission, Infectious ; Hepacivirus ; Hepatitis B ; Hepatitis B virus ; HIV ; HIV Infections ; Humans ; Immunization ; Infection Control ; Korea ; Latex Hypersensitivity ; Needlestick Injuries ; Occupational Diseases ; Occupational Exposure ; Occupational Health ; Post-Exposure Prophylaxis ; Respiratory Tract Infections ; Tuberculosis ; Violence ; Viruses ; World Health Organization

BACKGROUND/AIMS: Revaprazan (Revanex(R)) is a novel proton pump inhibitor (PPI) that has a somewhat different effect on proton pump compared with the other PPI's, also (called as 'acid pump antagonist'). We aimed to examine the false negative rate of 13C-urea breath test (UBT) in the patients with Helicobacter pylori (H. pylori) associated peptic ulcer disease who were treated with revaprazan and evaluate the anti-urease activity of revaprazan. METHODS: Total 55 patients were enrolled in this study. They received EGD examination between January 2009 and December 2009 and diagnosed histologically as H. pylori associated peptic ulcer disease. All patients took revaprazan only. Three patients were excluded because of underlying chronic disease and inappropriate breath sampling. The remaining 52 patients had UBT at 0, 2 and 4 weeks of revaprazan use. After 2 weeks of the cessation of revaprazan, they had the fourth UBT. RESULTS: At 2 and 4 weeks, the false negative rates of UBT were 5.8% and 23.1%, respectively (p=0.05). After 2 weeks of the cessation, the cases of the false negative result were five. Four out of five patients had prolonged negative results on two or three successive tests, and baseline 13C difference value did not predict the false negative results. CONCLUSIONS: False negative results of UBT were common and increased with prolonged use of acid pump antagonist. As PPI, it had also anti-urease activity and most patients (47/52, 90.4%) reverted to positive results by 2 weeks after the cessation of taking the medication.
*Breath Tests ; Carbon Isotopes ; False Negative Reactions ; Female ; Helicobacter Infections/complications/*diagnosis ; *Helicobacter pylori ; Humans ; Male ; Middle Aged ; Peptic Ulcer/*drug therapy/microbiology ; Proton Pump Inhibitors/*therapeutic use ; Pyrimidinones/*therapeutic use ; Tetrahydroisoquinolines/*therapeutic use ; Urea/*diagnostic use