Nowadays, Klebsiella oxytoca is described as a causative organism for antibiotic-associated hemorrhagic colitis (AAHC). Here we report two cases of pediatric AAHC, from which K. oxytoca was cultured after starting amoxicillin-clavulanate or amoxicillin treatment. The patients developed severe abdominal pain and a large amount of bloody diarrhea. K. oxytoca was obtained in intestinal fluid culture of a boy through the colonoscopy. On the other hand, colonic tissue culture and intestinal fluid culture were negative of the other patient. K. oxytoca was detected in stool culture when he was admitted. These cases showed characteristic endoscopic findings of segmental hemorrhagic colitis, and both boys recovered spontaneously within 2–3 days after they stopped taking the antibiotics. Therefore, in children who develop relatively large amount of bloody diarrhea after antibiotic treatment, we should consider AAHC caused by K. oxytoca.
Abdominal Pain ; Amoxicillin ; Anti-Bacterial Agents ; Child ; Colitis* ; Colon ; Colonoscopy ; Diarrhea ; Hand ; Humans ; Klebsiella oxytoca* ; Klebsiella* ; Male

Enteric infections have previously been postulated to play a role in the pathogenesis of inflammatory bowel disease (IBD), however, little evidence exists in the etiologic role of specific enteric infections in the development of IBD. When encountered in the setting of IBD, enteric infections pose a clinical challenge in management given the competing treatment strategies for infectious conditions and autoimmune disorders. Here we present the case of a young male with enteric infections complicating a new diagnosis of IBD. Our patient's initial clinical presentation included diagnoses of Klebsiella oxytoca isolation and Clostridium difficile infection. Directed therapies to include withdrawal of antibiotics and fecal microbiota transplantation were performed without resolution of clinical symptoms. Given persistence of symptoms and active colitis, the patient was diagnosed with ulcerative colitis (UC), requiring treatments directed at severe UC to include cyclosporine therapy. The finding of multiple enteric infections in a newly presenting patient with IBD is an unexpected finding that has treatment implications.
Anti-Bacterial Agents ; Clostridium difficile ; Colitis ; Colitis, Ulcerative* ; Cyclosporine ; Diagnosis ; Fecal Microbiota Transplantation ; Humans ; Inflammatory Bowel Diseases ; Klebsiella oxytoca ; Male ; Ulcer*

BACKGROUND: This study was conducted to evaluate the impact of the media type used for direct identification of colonies on the surveillance culture of carbapenem-resistant Enterobacteriaceae (CRE) by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). METHODS: CRE surveillance culture isolates were subjected to species identification using the MALDI Biotyper (Bruker Daltonics, Germany) for 2 months starting in March 2017. Four types of media were evaluated: blood agar (BA), Mueller Hinton agar (MH), MacConkey agar (Mac), and MacConkey agar containing imipenem of 1 µg/mL (IMP-Mac). CRE-like colonies on IMP-Mac and their subculture colonies on the other media were tested after overnight incubation and extended incubation for one additional day. The percent identification and score value were analyzed for each media types and incubation time when the identification was correct at the genus level. RESULTS: A total of 117 isolates were identified as 84 Klebsiella pneumoniae, 12 Escherichia coli, 9 Enterobacter cloacae, 5 Klebsiella oxytoca, 4 Enterobacter aerogenes, and 2 Raoultella ornithinolytica. The successful identification rates (SIR) for BA and MH were 98.3% and 97.4% (P=0.9), respectively, while those for Mac and IMP-Mac were 82.1% (P < 0.001) and 70.9% (P < 0.001), respectively. After extended incubation, SIRs were decreased to 96.6%, 96.6% (P=1.0), 61.5% (P < 0.001), and 58.1% (P < 0.001) on BA, MH, Mac, and IMP-Mac, respectively. The average score values were significantly lower for Mac (2.017±0.22) and IMP-Mac (1.978±0.24) than for BA (2.213±0.16) (P < 0.001). CONCLUSIONS: The low performance of the MALDI Biotyper applied directly to the colonies grown on Mac or IMP-Mac indicates that subculture on BA or MH is preferable before identification by MALDI-TOF MS.
Agar ; Enterobacter aerogenes ; Enterobacter cloacae ; Enterobacteriaceae* ; Escherichia coli ; Imipenem ; Klebsiella oxytoca ; Klebsiella pneumoniae ; Mass Spectrometry ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization*

Cadaverine is a biogenic amine that has the potential to become an important platform chemical for the production of industrial polymers, such as polyamides and polyurethanes. We reported here a lysine decarboxylase from Klebsiella oxytoca. The lysine decarboxylase from Klebsiella oxytoca was cloned to Escherichia coli to get the strain LN18. The specific activity of the crude protein from LN18 reached 30 000 U. The molecular weight was about 80 kDa. The optimum temperature and pH of the crude protein were 55 ℃ and 5.5 respectively. The specific activity could keep over 30% at pH 8.0 compared the one at pH 5.5, much difference from Escherichia coli lysine decarboxylase CadA. Mg²⁺ was positive to the specific activity, whereas Fe²⁺, Zn²⁺ and Ca²⁺ were negative.
Bacterial Proteins ; genetics ; metabolism ; Cadaverine ; Carboxy-Lyases ; genetics ; metabolism ; Escherichia coli ; metabolism ; Hydrogen-Ion Concentration ; Klebsiella oxytoca ; enzymology ; genetics ; Temperature

To get the tolerability and consumption of Klebsiella oxytoca on major inhibitors in lignocelluloses hydrolysate, we studied the effect of acetic acid, furfural and 5-hydroxymethylfurfural on production of 2,3-butanediol by Klebsiella oxytoca. The metabolites of furfural and 5-hydroxymethylfurfural were measured. The results show that when acetic acid, furfural and 5-hydroxymethylfurfural was individually added, tolerance threshold for Klebsiella oxytoca was 30 g/L, 4 g/L and 5 g/L, respectively. Acetic acid was likely used as substrate to produce 2,3-butanediol. The yield of 2,3-butanediol increased when acetic acid concentration was lower than 30 g/L. In the fermentation, more than 70% 5-hydroxymethylfurfural was converted to 2,5-furandimethanol. All furfural and the rest of 5-hydroxymethylfurfural were metabolized by Klebsiella oxytoca. It showed that in the detoxification process of 2,3-butanediol production using lignocelluloses hydrolysate, furfural should be given priority to remove and a certain concentration of acetic acid is not need to removal.
Acetic Acid ; chemistry ; Butylene Glycols ; metabolism ; Fermentation ; Furaldehyde ; analogs & derivatives ; chemistry ; Klebsiella oxytoca ; metabolism ; Lignin ; chemistry ; metabolism

PURPOSE: This study was performed to describe the clinical manifestations of hospitalized children due to varicella-zoster virus (VZV) infection. METHODS: This study included 40 children who were hospitalized for varicella or herpes zoster at Seoul National University Children's Hospital, 2009-2012. Diagnosis of VZV infection was confirmed by VZV PCR or culture from vesicular fluid. Medical records were reviewed to collect clinical features and outcome, antiviral treatment, history of varicella vaccination, and underlying diseases. RESULTS: Sixteen patients with varicella and 24 patients with herpes zoster were included. Their median age was 10.5 years (16 days-19 years). Thirty-five (87.5%) patients had underlying diseases. Among 24 patients with herpes zoster, 11 patients had previous history of varicella and 1 had herpes zoster. Twenty patients (50%) had a history of varicella vaccination, and 19 immunocompromised patients had VZV infection despite of vaccination. Most (95%) patients were treated by intravenous or oral acyclovir, and no treatment failure of intravenous acyclovir was found. The median duration of fever was 4.4 days (1-10 days), and that of antiviral treatment was 12 days (7-23 days) in immunocompromised patients. Immunocompromised patients received longer duration of antiviral treatment than imunocompetent patients (P=0.014). Eleven (27.5%) immunocompromised patients had postherpetic neuralgia, 2 (5%) had proven co-infection by Streptococcus pyogenes and Klebsiella oxytoca, and 1 (2.5%) complicated with pneumonia. CONCLUSION: Immunocompromised children require longer duration of treatment and are at risk of severe complication associated with VZV infection. Early initiation of antiviral therapy and close monitoring are necessary for those in immunocpompromised conditions.
Acyclovir ; Chickenpox ; Child ; Child, Hospitalized* ; Coinfection ; Diagnosis ; Fever ; Herpes Zoster ; Herpesvirus 3, Human* ; Humans ; Immunocompromised Host ; Klebsiella oxytoca ; Medical Records ; Neuralgia, Postherpetic ; Pneumonia ; Polymerase Chain Reaction ; Seoul ; Streptococcus pyogenes ; Treatment Failure ; Vaccination

PURPOSE: Necrotizing fasciitis is a rare, life-threatening, and rapidly progressive soft tissue infection associated with extensive necrosis. Despite recent advances in its management, outcomes have not improved and the mortality rate from this disease is still high. The objective of this study was to identify the predictive factors of mortality for patients diagnosed with necrotizing fasciitis in the ED. METHODS: A total of 38 necrotizing fasciitis cases diagnosed by an emergency department from January 2001 to April 2012 were retrospectively reviewed. RESULTS: Mean serum lactate levels were significantly higher in non-survivors than survivors (8.03+/-4.48 vs. 3.26+/-2.46, p=0.001). Serum glucose levels, arterial pCO2, and HCO3 values were significantly lower in non-survivors than survivors (114.75+/-78.01 vs. 203.92+/-122, p=0.027;25.02+/-6.82 vs. 32.74+/-7.06, p=0.005; 13.76+/-6.08 vs. 20.63+/-5.12, p=0.002, respectively). Microorganisms isolated included coagulase-negative Staphylococci from seven patients (18.4%), Acinetobacter baumannii from six patients (15.8%), Enterococcus faecium from five patients (13.2%), Staphylococcus aureus from five patients (13.2%), Beta-hemolytic Streptococcus from three patients (7.9%), Enterococcus faecalis from three patients (7.9%), Escherichia coli from two patients (5.3%), Pseudomonas aeruginosa from two patients (5.3%), Enterobacter cloaca from two patients (5.3%), Klebsiella oxytoca from two patients (5.3%), and Klebsiella pneumonia from two patients (5.3%). More Acinetobacter baumannii were cultured from the non-survival group than the survival group (p=0.022), while there was no statistical difference from surgical treatment between the survivor and non-survivor group (p=0.460). Interestingly, serum lactate levels above 4.0 mmol/L were a predictor of mortality in the ED (OR, 20.000; confidence interval, 1.796-222.777). CONCLUSION: Initial serum lactate levels above 4 mmol/Larea predictor of mortality in patients diagnosed with necrotizing fasciitis in the ED.
Acinetobacter baumannii ; Blood Glucose ; Cloaca ; Emergencies* ; Enterobacter ; Enterococcus faecalis ; Enterococcus faecium ; Escherichia coli ; Fasciitis, Necrotizing* ; Humans ; Klebsiella ; Klebsiella oxytoca ; Lactic Acid ; Mortality* ; Necrosis ; Pneumonia ; Pseudomonas aeruginosa ; Retrospective Studies ; Soft Tissue Infections ; Staphylococcus aureus ; Streptococcus ; Survivors

PURPOSE: Necrotizing fasciitis is a rare, life-threatening, and rapidly progressive soft tissue infection associated with extensive necrosis. Despite recent advances in its management, outcomes have not improved and the mortality rate from this disease is still high. The objective of this study was to identify the predictive factors of mortality for patients diagnosed with necrotizing fasciitis in the ED. METHODS: A total of 38 necrotizing fasciitis cases diagnosed by an emergency department from January 2001 to April 2012 were retrospectively reviewed. RESULTS: Mean serum lactate levels were significantly higher in non-survivors than survivors (8.03+/-4.48 vs. 3.26+/-2.46, p=0.001). Serum glucose levels, arterial pCO2, and HCO3 values were significantly lower in non-survivors than survivors (114.75+/-78.01 vs. 203.92+/-122, p=0.027;25.02+/-6.82 vs. 32.74+/-7.06, p=0.005; 13.76+/-6.08 vs. 20.63+/-5.12, p=0.002, respectively). Microorganisms isolated included coagulase-negative Staphylococci from seven patients (18.4%), Acinetobacter baumannii from six patients (15.8%), Enterococcus faecium from five patients (13.2%), Staphylococcus aureus from five patients (13.2%), Beta-hemolytic Streptococcus from three patients (7.9%), Enterococcus faecalis from three patients (7.9%), Escherichia coli from two patients (5.3%), Pseudomonas aeruginosa from two patients (5.3%), Enterobacter cloaca from two patients (5.3%), Klebsiella oxytoca from two patients (5.3%), and Klebsiella pneumonia from two patients (5.3%). More Acinetobacter baumannii were cultured from the non-survival group than the survival group (p=0.022), while there was no statistical difference from surgical treatment between the survivor and non-survivor group (p=0.460). Interestingly, serum lactate levels above 4.0 mmol/L were a predictor of mortality in the ED (OR, 20.000; confidence interval, 1.796-222.777). CONCLUSION: Initial serum lactate levels above 4 mmol/Larea predictor of mortality in patients diagnosed with necrotizing fasciitis in the ED.
Acinetobacter baumannii ; Blood Glucose ; Cloaca ; Emergencies* ; Enterobacter ; Enterococcus faecalis ; Enterococcus faecium ; Escherichia coli ; Fasciitis, Necrotizing* ; Humans ; Klebsiella ; Klebsiella oxytoca ; Lactic Acid ; Mortality* ; Necrosis ; Pneumonia ; Pseudomonas aeruginosa ; Retrospective Studies ; Soft Tissue Infections ; Staphylococcus aureus ; Streptococcus ; Survivors

BACKGROUND: Impetigo is a common bacterial infection caused by Staphylococcus aureus, and group A beta-hemolytic Streptococcus or both. Recently, S. aureus has been reported as the most frequently isolated pathogen of impetigo and the incidence of methicillin-resistant S. aureus (MRSA) among patients with impetigo has increased. OBJECTIVE: To investigate the predominant microorganism and the antibiotic susceptibility of the impetigo causative pathogen. METHODS: Bacterial culture and antimicrobial susceptibility testing were performed in patients with impetigo from June 2006 to May 2012. RESULTS: Of 164 patients, bacteria were cultured from 139 patients. Among them, S. aureus was isolated from 114 (82%) patients. The others were Acinetobacter baumannii, Enterobactercloacae, Enterococcus species, Enterococcus faecium, Enterococcus faecalis, Klebsiella oxytoca, and Candida albicans. The resistance rates of S. aureus against antibiotics were as follows: penicillin, 95.6%; erythromycin, 43.9%; fusidicacid, 38.1%; clindamycin, 24.5%; gentamycin, 21%; tetracycline, 12.3%; trimethoprim-sulfamethoxazole, 0.9%; ciprofloxacin, 0%; habekacin, 0%; linezolid, 0%; teicoplanin, 0%; and vancomycin, 0%. Thirty-four (29.8%) S. aureus isolates were MRSA, and the prevalence of MRSA increased during the 6-year period. CONCLUSION: The most predominant pathogen in impetigo was S. aureus, which was sensitive to ciprofloxacin, habekacin, linezolid, trimethoprim-sulfamethoxazole, teicoplanin, and vancomycin. An increase in the prevalence of MRSA was observed during the 6-year period, and the effective antibiotics for MRSA were trimethoprim-sulfamethoxazole, teicoplanin and vancomycin.
Acetamides ; Acinetobacter baumannii ; Anti-Bacterial Agents ; Bacteria ; Bacterial Infections ; Candida albicans ; Ciprofloxacin ; Clindamycin ; Dibekacin ; Enterococcus ; Enterococcus faecalis ; Enterococcus faecium ; Erythromycin ; Gentamicins ; Humans ; Impetigo ; Incidence ; Klebsiella oxytoca ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Oxazolidinones ; Penicillins ; Prevalence ; Staphylococcus aureus ; Streptococcus ; Teicoplanin ; Tetracycline ; Trimethoprim, Sulfamethoxazole Drug Combination ; Vancomycin ; Linezolid

BACKGROUND: In 2010, the Clinical and Laboratory Standards Institute (CLSI) revised breakpoints for cephalosporins and carbapenems and indicated that extended-spectrum beta-lactamase (ESBL) testing is no longer necessary for Enterobacteriaceae. We compared the results of the CLSI 2010 and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) MIC breakpoints for Enterobacteriaceae producing ESBL and/or plasmid-mediated AmpC beta-lactamase (PABL). METHODS: A total of 94 well-characterized clinical isolates of Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Salmonella spp., Shigella spp., Citrobacter freundii, Enterobacter aerogenes, Enterobacter cloacae, and Serratia marcescens were analyzed. Of them, 57 were ESBL producers, 24 were PABL producers, and 13 were ESBL plus PABL co-producers. Broth microdilution MIC tests were performed for cefotaxime, ceftazidime, aztreonam, cefepime, and imipenem. RESULTS: Among the 94 isolates containing ESBL and/or PABL, the number of isolates that were susceptible to cefotaxime, ceftazidime, aztreonam, cefepime, and imipenem according to the CLSI 2010 vs. the EUCAST breakpoints were 4 (4.3%) vs. 4 (4.3%); 26 (27.7%) vs. 8 (8.5%); 37 (39.4%) vs. 14 (14.9%); 71 (75.5%) vs. 31 (33.0%); and 76 (80.9%) vs. 90 (95.7%), respectively. Of the 18 isolates that were not susceptible to imipenem according to the CLSI 2010 breakpoints, 13 isolates (72.2%) were P. mirabilis. CONCLUSION: The CLSI 2010 MIC breakpoints without tests to detect ESBL and/or PABL for Enterobacteriaceae could be unreliable. Thus, special tests for ESBLs and AmpC beta-lactamases are required to detect the resistance mechanisms involved.
Aztreonam ; Bacterial Proteins ; beta-Lactamases ; beta-Lactams ; Carbapenems ; Cefotaxime ; Ceftazidime ; Cephalosporins ; Citrobacter freundii ; Enterobacter aerogenes ; Enterobacter cloacae ; Enterobacteriaceae ; Escherichia coli ; Imipenem ; Klebsiella oxytoca ; Klebsiella pneumoniae ; Proteus mirabilis ; Salmonella ; Serratia marcescens ; Shigella