Classificação dos graus de lesões de aerossaculite em perus associadas com enterobactérias / [Classification of the levels of the airsacculitis injuries in turkeys associated with Enterobacteriaceae]

Foram padronizados os graus de lesões dos sacos aéreos em perus com aerossaculite, associadas com a presença de isolados de enterobactérias nesses órgãos. Um total de 110 amostras de sacos aéreos de perus machos com aerossaculite foi coletado para o estudo. Durante o processo de abate, as amostras foram coletadas por meio de swabs e submetidas a três métodos de armazenamento (imediato, congelado ou pré-incubado após congelamento) para posterior comparação das suas eficiências de isolamento. Os gêneros da família Enterobacteriaceae foram identificados pelas séries bioquímicas EPM, MILi e citrato de Simmons. O crescimento bacteriano ocorreu em 43,64% das amostras. Neste estudo, quatro padrões de lesões de aerossaculite foram identificados de acordo com as características patológicas dos sacos aéreos. Os principais gêneros de enterobactérias identificadas foram: Escherichia coli, Citrobacter, Proteus, Edwardsiella, Morganella, Kluyvera, Salmonella e Klebsiella. Foi observado que os graus padronizados como 3 e 4 apresentaram maior variedade de gêneros bacterianos. O armazenamento imediato apresentou maior porcentagem de positividade, 41,82%, no entanto o pré-incubado após congelamento se apresentou mais eficaz em relação à quantidade de colônias.(AU)

The degrees of air sac lesions in turkeys with airsacculitis were standardized, associated with the presence of Enterobacteriaceae isolated from these organs. A total of 110 samples of air sacs from male turkeys with airsacculitis were collected and analyzed. During the slaughtering process, the sample collection was done using swabs and submitted to three storage methods (immediate, frozen, or pre incubated after freezing) for further comparison of their isolated efficiency. The bacterial genera of the family Enterobacteriaceae were identified biochemical series EPM, MILi and Simmons citrate. Bacterial growth occurred in 43.64% of samples. In this study, four patterns of aerossaculitis lesions were identified according to the pathological characteristics of air sacs. The frequencies of the Enterobacteriaceae isolated identified in the samples were: Escherichia coli, Citrobacter, Proteus, Edwardsiella, Morganell, Kluyvera, Salmonella and Klebsiella. Otherwise, it was observed that the levels already standardized as level three and four showed higher variety of genus. The immediate storage showed higher percentage of positivity at 41.82%, however, the pre incubated after freezing showed more efficiency in relation to the quantity of colonies.(AU)

Infecção de trato urinário inferior por Citrobacter sp em cadela com hipoadrenocorticismo / Citrobacter sp lower urinary tract infection in a bitch with hypoadrenocorticism

Citrobacter sp. é um microrganismo frequentemente encontrado em vagina de cadelas, mas corresponde a menos de 3% do total de microrganismos isolados em urocultura. O hipoadrenocorticismo (HA) é uma doença endócrina incomum e que leva a poliúria e hipostenúria. O objetivo deste trabalho é relatar o caso de uma fêmea da espécie canina, da raça Teckel, 11 anos, atendida com queixa de urina de odor alterado há vários dias, além de vômito, diarreia e inapetência há três dias, e poliúria e polidipsia há 2 meses, com histórico de tratamento anterior com mitotano para hiperadrenocorticismo. O diagnóstico foi de ITU por Citrobacter sp., além de HA iatrogênico. Como destaques nos exames, relação sódio:potássio de 22,6 foi observada, sugestiva de HA, que foi confirmado por teste de estimulação com ACTH, além de urina inicialmente hipostenúrica (densidade 1,006), o que pode ser atribuído ao washout medular renal devido à hiponatremia causada pelo hipoadrenocorticismo. O tratamento foi feito com amoxicilina associada a ácido clavulânico por 20 dias, além da terapia específica para HA com prednisona e fludrocortisona, que foi continuado. A paciente recuperou-se bem, a densidade urinária aumentou após início do tratamento para HA e não houve recidiva da ITU em período de acompanhamento de 8 meses. Acredita-se que a baixa densidade urinária causada pelo HA tenha sido fator essencial para a oco

Citrobacter sp. is a normal constituent of bitches’ vagina, but it is related to less than 3% of total isolated microorganism in uroculture. Hypoadrenocorticism (HA) is an endocrine disease uncommonly diagnosed that leads to polyuria and hypostenuria. The aim of this work is report the case of a Teckel bitch, 11 years old, attended with complaint of altered urinary smell for several days, besides vomiting, diarrhea and inappetence for three days, and polyuria and polydispsia for two months, with previous mitotane treatment for hyperadrenocorticism. The diagnosis was Citrobacter UTI, besides iatrogenic HA. The most important exam results include sodium:potassium ratio of 22.6, suggestive of HA, that was confirmed by ACTH stimulation test. Besides, hypostenuria (urinary specific gravity – USG - of 1.006) was noted, attributed to renal medular washout due to hyponatremia seen in HA. Therapy comprised amoxicillin associated with clavulanic acid for 20 days, in addition to specific therapy for AH with prednisone and fludrocortisone. The patient recovery well, USG increased after the beginning of the treatment for HA and there was no UTI reinfection for a 8 month period. It is believed that low USG due to HA was essential for the occurrence of Citrobacter UTI.

Infecção de trato urinário inferior por Citrobacter sp em cadela com hipoadrenocorticismo / Citrobacter sp lower urinary tract infection in a bitch with hypoadrenocorticism

Citrobacter sp. é um microrganismo frequentemente encontrado em vagina de cadelas, mas corresponde a menos de 3% do total de microrganismos isolados em urocultura. O hipoadrenocorticismo (HA) é uma doença endócrina incomum e que leva a poliúria e hipostenúria. O objetivo deste trabalho é relatar o caso de uma fêmea da espécie canina, da raça Teckel, 11 anos, atendida com queixa de urina de odor alterado há vários dias, além de vômito, diarreia e inapetência há três dias, e poliúria e polidipsia há 2 meses, com histórico de tratamento anterior com mitotano para hiperadrenocorticismo. O diagnóstico foi de ITU por Citrobactersp., além de HA iatrogênico. Como destaques nos exames, relação sódio:potássio de 22,6 foi observada, sugestiva de HA, que foi confirmado por teste de estimulação com ACTH, além de urina inicialmente hipostenúrica (densidade 1,006), o que pode ser atribuído ao washout medular renal devido à hiponatremia causada pelo hipoadrenocorticismo. O tratamento foi feito com amoxicilina associada a ácido clavulânico por 20 dias, além da terapia específica para HA com prednisona e fludrocortisona, que foi continuado. A paciente recuperou-se bem, a densidade urinária aumentou após início do tratamento para HA e não houve recidiva da ITU em período de acompanhamento de 8 meses. Acredita-se que a baixa densidade urinária causada pelo HA tenha sido fator essencial para a ocorrência da ITU por Citrobacter.

Citrobacter sp. is a normal constituent of bitches' vagina, but it is related to less than 3% of total isolated microorganism in uroculture. Hypoadrenocorticism (HA) is an endocrine disease uncommonly diagnosed that leads to polyuria and hypostenuria. The aim of this work is report the case of a Teckel bitch, 11 years old, attended with complaint of altered urinary smell for several days, besides vomiting, diarrhea and inappetence for three days, and polyuria and polydispsia for two months, with previous mitotane treatment for hyperadrenocorticism. The diagnosis was Citrobacter UTI, besides iatrogenic HA. The most important exam results include sodium:potassium ratio of 22.6, suggestive of HA, that was confirmed by ACTH stimulation test. Besides, hypostenuria (urinary specific gravity ­ USG - of 1.006) was noted, attributed to renal medular washout due to hyponatremia seen in HA. Therapy comprised amoxicillin associated with clavulanic acid for 20 days, in addition to specific therapy for AH with prednisone and fludrocortisone. The patient recovery well, USG increased after the beginning of the treatment for HA and there was no UTI reinfection for a 8 month period. It is believed that low USG due to HA was essential for the occurrence of Citrobacter UTI.

Sudden Deaths of Neonates Receiving Intravenous Infusion of Lipid Emulsion Contaminated with Citrobacter freundii

At an intensive care unit, four neonates died consecutively within 80 minutes. Citrobacter freundii was isolated from blood samples of the 4 patients. It was also cultured from the leftover SMOFlipid that had been infused intravenously into the patients. In this in vitro study, we evaluated the bacterial growth kinetics and change in size of fat globules in SMOFlipid contaminated with C. freundii. Following the growth of bacteria, pH of SMOFlipid decreased to < 6, and the number of fat globules larger than 5 µm increased. Pulmonary fat embolism is proposed as a possible cause of the sudden deaths as well as fulminant sepsis.

Evaluation of Six Phenotypic Methods for the Detection of Carbapenemases in Gram-Negative Bacteria With Characterized Resistance Mechanisms

BACKGROUND: We compared the performance of the modified Hodge test (MHT), Triton Hodge test (THT), Carba NP test (CNPt), simplified Carba NP test (CNPt-direct), blue-Carba NP test (BCT), and carbapenem inactivation method (CIM) for rapid and accurate carbapenemase detection. METHODS: The methods were evaluated by using 256 gram-negative isolates, including 197 Enterobacteriaceae (79 Enterobacter spp., 74 Klebsiella spp., 33 Escherichia coli, 10 Citrobacter spp., and 1 Serratia marcescens), 51 Acinetobacter baumannii, and 8 Pseudomonas aeruginosa strains. The collection included 117 non-carbapenemase, 18 Klebsiella pneumoniae carbapenemases (KPC) producers, 46 New Delhi metallo-β-lactamases (NDM) producers, 11 imipenemases (IMP) producers, and 51 oxacillinases (OXA) producers, and 13 strains harboring two different carbapenemase genes. RESULTS: The specificity of the THT (91.5%) was significantly lower than other methods, each of which had 100% specificity (P0.999). Because of improved detection of NDM carriers, THT showed significantly higher sensitivity than the MHT (84.9% vs 75.5%, P<0.001). However, poor performances in detecting OXA still influenced the sensitivities of the CNPt (66.2%) and BCT (82.0%), as well as the MHT and THT. CONCLUSIONS: CNPt-direct and CIM demonstrated the best performance for the efficient detection of carbapenemase among the six evaluated methods. Except the MHT and THT, the detection of carbapenemase-producing Enterobacteriaceae by all the other methods was acceptable, when the OXA-type carbapenemase was not prevalent.

Efficient expression and characterization of a cold-active endo-1, 4-β -glucanase from Citrobacter farmeri by co-expression of Myxococcus xanthus protein S

Background: Cold-active endo-1, 4-β-glucanase (EglC) can decrease energy costs and prevent product denaturation in biotechnological processes. However, the nature EglC from C. farmeri A1 showed very low activity (800 U/L). In an attempt to increase its expression level, C. farmeri EglC was expressed in Escherichia coli as an N-terminal fusion to protein S (ProS) from Myxococcus xanthus. Results: A novel expression vector, pET(ProS-EglC), was successfully constructed for the expression of C. farmeri EglC in E. coli. SDS-PAGE showed that the recombinant protein (ProS-EglC) was approximately 60 kDa. The activity of ProS-EglC was 12,400 U/L, which was considerably higher than that of the nature EglC (800 U/L). ProS-EglC was active at pH 6.5-pH 8.0, with optimum activity at pH 7.0. The recombinant protein was stable at pH 3.5-pH 6.5 for 30 min. The optimal temperature for activity of ProS-EglC was 30°C-40°C. It showed greater than 50% of maximum activity even at 5°C, indicating that the ProS-EglC is a cold-active enzyme. Its activity was increased by Co2+ and Fe2+, but decreased by Cd2+, Zn2+, Li+, methanol, Triton-X-100, acetonitrile, Tween 80, and SDS. Conclusions: The ProS-EglC is promising in application of various biotechnological processes because of its cold-active characterizations. This study also suggests a useful strategy for the expression of foreign proteins in E. coli using a ProS tag.

Periungual Abscess Caused by Citrobacter braakii in a Patient with Chronic Paronychia

No abstract available.

Clinico-microbiological study of Citrobacter isolates from various clinical specimens and detection of β-lactamase production.

Citrobacter species have been reported to cause a wide spectrum of infections in humans and invasive infections are associated with a high mortality rate, with 33 to 48% of patients succumbing to Citrobacter bacteraemia. The high mortality rate associated with Citrobacter infections may be due in part to ineffective empirical antibiotic therapy. Citrobacter has been found to produce SHV and TEM derived Extended spectrum beta lactamases in addition to chromosomal inducible AmpC beta - lactamases which could be contributing to increasing drug resistance. The aims of the study were to detect the prevalence of Citrobacter infections with its associated risk factors, antibiotic susceptibility patterns and determination of beta-lactamase activity- both extended spectrum beta - lactamase and AmpC beta-lactamase activity among Citrobacter isolates. The isolates were identified by standard microbiological procedures. ESBL detection was by double disc diffusion method and AmpC beta-lactamase detection was done using Cefotaxime and Cefoxitin discs. C. braakii (33.3%) was the commonest genomospecies identified followed by C. freundii (21.3%) and C. amalonaticus (16.66 %) among 150 Citrobacter isolates. Diabetes mellitus was the major risk factor. Imipenem (100%)was most effective whereas 98% showed resistance to Ampicillin; carbapenems and fourth generation Cefipime showed better sensitivity than third generation cephalosporins. The study highlights the need for informed antibiotic treatment guided by routine antimicrobial susceptibility and knowledge of the ESBL status of the isolate, the outcome of which undoubtedly will be better patient care.

Unusual CAPD Citrobacter freundii Peritonitis Complicated by a Fungal Infection, Identified by 16s Ribosomal RNA Gene Sequencing / 대한내과학회지

We present a case of continuous ambulatory peritoneal dialysis peritonitis caused by Citrobacter freundii complicated by a fungal infection with abscess formation. A 34-year-old woman was admitted to our hospital with abdominal pain. Isolate cultures were confirmed as Citrobacter freundii by DNA sequencing of the 16s ribosomal ribonucleic acid (RNA). Antibiotic therapy was ineffective and Candida tropicalis was isolated in follow-up blood cultures. We administered an antifungal agent and removed the peritoneal catheter. A sudden fever developed, and abdominal computed tomography showed intra-abdominal abscesses. Percutaneous drainage was performed, but no bacteria were cultured. After draining the abscesses, the patient recovered. Citrobacter species are unusual pathogens in peritonitis, and fungal peritonitis is a serious complication of bacterial peritonitis. Indwelling catheters should be removed and appropriate antibiotic therapy provided. Suspicion of a fungal infection combined with bacterial peritonitis will improve the prognosis of patients on peritoneal dialysis.

Circulação de Enterobactérias no Parque Nacional Serra da Capivara (PNSC), Piauí-Brasil: sua prospectiva dotrinômio zoonótico animal, homem, ambiente / Circulação de Enterobactérias no Parque Nacional Serra da Capivara (PNSC), Piauí-Brasil: sua prospectiva do trinômio zoonótico animal, homem, ambiente

O Parque Nacional Serra da Capivara (PNSC) é um ambiente propício para o desenvolvimento e conservação de grande número de espécies endêmicas da caatinga, além de ser uma região de importância ímpar, pois é o maior sítio arqueológico do Brasil. A água nesta região é escassa e o contato das pessoas e seus animais domésticos e de criação com os animais silvestres faz com que aumente a possibilidade de circulação de possíveis patógenos, possibilitando a emergência de doenças tanto no homem quanto em animais. Este trabalho teve como objetivo analisar a presença e circulação de bactérias potencialmente enteropatogênicas e zoonóticas na região do Parque Nacional Serra da Capivara, localizado no sudeste do Estado do Piauí – Brasil. Coletas de amostras de água, fezes humanas e de animais silvestres e de criação foram realizadas em diferentes regiões no interior e no seu entorno,durante as idas ao campo, computando um montante de 170 amostras coletadas. (...) Não foi possível o isolamento de amostras do gênero Campylobacter, importante enteropatógeno de impacto para a Saúde Pública. O percentual de resistência das amostras a pelo menos uma das drogas testadas foi de 71 por cento sendo mais representativos para os fármacos: penicilina, cefoxitina e tetraciclina. A vigilância dos sorovares de Salmonella em ambientes aquáticos constitui um importante elemento para o monitoramento de infecções humanas e animais...

The National Park “Serra da Capivara” (PNSC) is a proper environment for the developmentand conservation of a great number of species of the caatinga and endemic species, it is also aregion of singular importance for being the largest archaeological site in Brazil. The water inthis region is scant and the contact of people and of their animal whether they are pets or forbreeding, with the wild animals incresases the probability of circulation of pathogens, makingit possible for the appearance of deseases in men and in other animals. This study had theobjective of analisyng the presence and circulation of bacterias potencially enteropathenogenic and zoonotic in the region of the National Park “Serra da Capivara”,located in the southeast of the state of Piaui – Brazil. Water samples, feces of humans and ofbreeding and wild animals were collected in different regions inside and in the surroundings of the PNSC, during trips to the field mounting up to 170 samples collected. Five Hundredand twenty two isolated were obtained to the following genus/species of the family Enterobacteriaceae: Escherichia coli (32.6 percent); Enterobacter spp. (22.8 percent); Klebsiella spp (11.8 percent); Salmonella spp (10 percent), Citrobacter spp. (9.2 percent) amongst others. The isolation of thesample of the genus Campylobacter, important enteropathogen of public health impact, wasnot possible. The percentage of resistence of the samples to, at least, one of the drugs testedwas from 71 percent and the percentages of resistence were more representative for the drugs: penicilin, cefoxitin and tetracyclin. The surveillance of Salmonella serovars in aquatic environment constitutes an important element for the monitoring of animal and humaninfections...

Efficacy of Debridement for Early Periprosthetic Joint Infection after Hip Arthroplasty / 대한고관절학회지

PURPOSE: In early prosthetic joint infection after hip arthroplasty, debridement with prosthesis retention may be performed for implant salvage, but the reported success rates are highly variable. Hence we reviewed the outcome of radical debridement and retention of prosthesis using established diagnostic criteria and surgical procedures in relation to significant variables including clinical characteristics, pathogenicity, and antibiotic treatment. MATERIALS AND METHODS: We retrospectively reviewed 20 patients (11 men and 9 women) with early prosthetic joint infection after unilateral hip arthroplasty, treated by radical debridement with retention of prosthesis from January 2000 to May 2011. Average follow-up period was 55 months (12-178 months). The outcome was evaluated and analyzed based on recurrence of infection and clinical (Harris hip score) and radiological criteria. RESULTS: Pathogens were isolated from 11 hips (methicillin-resistant Staphylococcus aureus [MRSA] in three, methicillin-resistant Staphylococcus epidermidis [MRSE] in two, methicillin-sensitive Staphylococcus aureus [MSSA] in one, Acinetobacter baumannii in two, Enterococcus faecalis in two patients, and Enterococcus, Citrobacter species in one). The mean duration of antibiotic administration was 43.5 days. Recurrence of infection was not observed in any case. Average Harris hip score was 91 points at the last follow-up. Revision surgery was not required for any reason including implant failure. Dislocation occurred in two hips after debridement and was treated conservatively. CONCLUSION: Radical debridement with prosthesis retention is an effective procedure for early prosthetic joint infection after hip arthroplasty in carefully selected patients and with early diagnosis.

Phytochemical, antimicrobial, insecticidal and brine shrimp lethality bioassay of the crude methanolic extract of ajuga parviflora benth

Methanolic extract of medicinal herb Ajuga parviflora Benth. was evaluated for phytochemical screening [the plant extract showed the presence of aromatic compounds, carbohydrates, glycosides, tannins, alkaloids, polyphenols, quinines and dions, aminophenols, steroids/sterols, flavonoids and terpenoids], antimicrobial activities against various strains of bacteria and fungi by using disc diffusion method and insecticidal activities against red flour beetle [Tribolium castaneum], wheat weevil [Sitophilis granaries] and their larvae. The crude extract showed anti-bacterial activity against all strains with a maximum zone of inhibition of 12mm diameter against Citrobacter and Pseudomonas aurogenosa. Standard drugs Ampicillin, Gentamicin and Amoxicillin were used in parallel. The crude extract did not show antifungal activity against the tested strains of fungi even at high doses. The crude methanolic extract was also used for insecticidal activity against the two types of insects and their larva. The extract showed no significant mortality in the tested strains. For brine shrimp lethality bioassay different concentrations 10, 100 and 1000ug/ml of the medicinal herb A. parviflora methanolic extract were used. After 24 hrs the percent mortality and LD[50] value was calculated through probit analysis. The LD[50] value of extract was 321.42microg/ml while that of standard drug cyclophosphamide was 16.09ug/ml

Emphysematous Pyelonephritis Caused by Citrobacter freundii in a Patient with Type 2 Diabetes and Neurogenic Bladder

Emphysematous pyelonephritis (EPN) is a rare, life-threatening complication of upper urinary tract infections that is characterized by the presence of gas in the renal parenchyma and perirenal space. It commonly occurs in diabetic patients. Escherichia coli are the most common causative organisms, with few reports implicating Citrobacter freundii as the etiologic agent in EPN. A 57-year-old woman with diabetes and neurogenic bladder visited at our department with confused mentality, myalgia, and general weakness. Further investigation revealed that the patient suffered from unilateral EPN with sepsis caused by C. freundii. The patient's condition was improved considerably with percutaneous drainage and use of intravenous antibiotics for several weeks. However, renal function eventually deteriorated to permanent renal failure, which required hemodialysis. In conclusion, C. freundii may be the causative pathogen of EPN in a patient with type 2 diabetes and neurogenic bladder.

Establishment and comparison of pulsed-field gel electrophoresis, multiple-locus variable number tandem repeat analysis and automated ribotyping methods for subtyping of Citrobacter strains / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To establish and compare the pulsed-field gel electrophoresis (PFGE), multiple-locus variable number tandem repeat analysis (MLVA) and automated ribotyping for subtyping of Citrobacter strains.</p><p><b>METHODS</b>PFGE protocol was optimized in terms of plug preparation procedure, restriction enzymes and configuration of electrophoretic parameters. MLVA method was evaluated by finding variable number tandem repeats in two genomes of Citrobacter strains. The ribotyping was performed by using the automated RiboPrinter system.</p><p><b>RESULTS</b>We optimized the plug preparation procedure, focused on the cell suspension concentration (turbidity of 2.5 to 3.5), SDS addition (no SDS needed) and lysis time (1 h), and selected the appropriate restriction enzyme (XbaI) and the electrophoretic parameters (1.0 s-20.0 s for 19 h) of PFGE. There was nearly no discriminatory power of MLVA between Citrobacter strains. For 51 Citrobacter strains, automated ribotyping gave a D-value of 0.9945, while PFGE gave a D-value of 0.9969. Both PFGE and automated ribotyping clustered strains from the same sources (with the same species from the same place at the same time identified as the same source) and divided strains from different sources (from different years, places and hosts) into different subtypes.</p><p><b>CONCLUSION</b>PFGE protocol established in this paper and automated ribotyping are suitable for application in Citrobacter subtyping.</p>

Results of Urine Culture and Antimicrobial Sensitivity Tests According to the Voiding Method Over 10 Years in Patients with Spinal Cord Injury

PURPOSE: We studied the results of urine cultures and antimicrobial sensitivity tests according to the voiding method used by spinal cord injury (SCI) patients over a recent 10-year period. MATERIALS AND METHODS: We retrospectively analyzed 1,236 urine samples and their antimicrobial sensitivity tests for 112 patients who had used only one voiding method between January 2000 and December 2009. The voiding methods were classified into four groups: clean intermittent catheterization (CIC), suprapubic catheterization, urethral Foley catheter, and spontaneous voiding. RESULTS: Of the 1,236 urine samples, 925 (74.8%) were positive and 279 (30.2%) had more than one bacteria. The CIC group showed the lowest rate of bacteriuria, colony counts, and polymicrobial infection (p<0.001). Causative organisms were mostly Gram-negative bacteria (84%), including Pseudomonas aeruginosa (22.9%), Escherichia coli (21.1%), Klebsiella species (6.7%), and Citrobacter species (6.3%). The rate of Gram-positive bacterial infection was 13.6%, and major pathogenic organisms were Streptococcus species (8.6%) and Staphylococcus species (2.6%). Major pathogenic organisms and the results of antimicrobial sensitivity tests differed according to the voiding method. CONCLUSIONS: Although the patient's condition and preferences are important when choosing the method of bladder management, CIC is the best voiding method for reducing urinary tract infections in SCI patients. When immediate use of antibiotics is needed for treatment of urinary tract infections, an appropriate antibiotic can be chosen according to the voiding method on the basis of our study and can be administered before the results of an antimicrobial sensitivity test are available.

Identification of Helicobacter pylori in Gallstone, Bile, and Other Hepatobiliary Tissues of Patients with Cholecystitis

BACKGROUND/AIMS: Bacterial infection is accepted as a precipitating factor in cholesterol gallstone formation, and recent studies have revealed the presence of Helicobacter species in the hepatobiliary system. We utilized the polymerase chain reaction (PCR) to establish the presence of bacterial DNA, including from Helicobacter species, in gallstones, bile juice, and gallbladder mucosa from patients with gallstones. METHODS: At cholecystectomy, 58 gallstones, 48 bile samples, and 46 gallbladder mucosa specimens were obtained and subjected to nested PCR using specific 16S rRNA primers of H. pylori and other bacteria. Bacterial species were identified by DNA sequencing analysis. Bacterial 16S rRNA was detected in 25 out of 36 mixed-cholesterol gallstones, 1 out of 10 pure-cholesterol gallstones, and 9 out of 12 pigmented stones. Furthermore, 16S rDNA sequencing identified Escherichia coli, Pseudomonas, Citrobacter, Klebsiella, and Helicobacter species. RESULTS: Helicobacter DNA was detected in 4 out of 58 gallstones, 6 out of 48 bile samples, and 5 out of 46 gallbladder specimens. Direct sequencing of Helicobacter amplicons confirmed strains of H. pylori in all four gallstones, five out of six bile samples, and three out of five gallbladder specimens. Almost all mixed-cholesterol gallstones appear to harbor bacterial DNA, predominantly E. coli. CONCLUSIONS: H. pylori was also found in the biliary system, suggesting that these bacteria are of etiological importance in gallstone formation.

Molecular and Phenotypic Characteristics of 16S rRNA Methylase-producing Gram-negative Bacilli / 대한임상미생물학회지

BACKGROUND: Recently a novel plasmid-mediated resistant mechanism that conferred high-level resistance to aminoglycoside via methylation of 16S rRNA was reported. The aims of this study were to determine the prevalence of the 16S rRNA methylase genes and to characterize the coresistance to other antibiotics in Gram-negative bacilli. METHODS: Consecutive non-duplicate Gram-negative bacilli were isolated from clinical specimens at a Korean secondary- and tertiary-care hospital from July 2006 to June 2007. The antimicrobial susceptibility was tested by the CLSI agar dilution method,and PCR was performed to detect the 16S rRNA methylase genes in the arbekacin-resistant isolates. RESULTS: In Gram-negative bacilli, the proportions of 16S rRNA methylase gene-positive isolates were 5% (75/1,471) in the secondary-carehospital and 4% (48/1,251) in the tertiary-care hospital, and the positive rates by species were 1% Escherichiae coli 16% (10/1,062), Klebsiella pneumoniae 16% (75/460), K. oxytoca 2% (1/44), Citrobacter spp. 9% (7/82), Enterobacter spp. 2% (4/181), Serratia marcescens 6% (6/100), Proteus miriabilis 4% (2/57), Achromobacter xylosoxidans 20% (1/5), Pseudomonas aeruginosa < 1% (1/505), Acinetobacter spp. 10% (11/112), and Stenotrophomonas maltophilia 2% (1/66), respectively. Among 16S rRNA methylase-positive isolates from secondary- and tertiary-care hospitals, 93% (70/75) and 90% (43/48), respectively, were armA positive, and others, except one rmtA positive isolate, were positive for the rmtB gene, according to PCR results. The rates of ESBL-positive and cefoxitin-resistant K. pneumoniae were 59% and 92%,s respectively. In addition, 91% of 16S rRNA methylase-producing K. pneumoniae were positive for qnrB. There were no MBL producers among 16S rRNA methylase-producing Pseudomonas and Acinetobacter species. CONCLUSION: The novel aminoglycoside-resistant mechanisms involving16S rRNA methylase were prevalent and widely distributed among Gram-negative bacilli in Korea, and other resistance mechanisms were commonly associated with 16S rRNA methylase-mediated resistance in Korea.

Prevalence of Extended-spectrum beta-lactamase among Enterobacteriacae Blood Isolates with Inducible AmpC beta-lactamase

BACKGROUND: Among the inducible AmpC beta-lactamase-producing members of the family Enterobacteriaceae such as Enterobacter spp., Citrobacter spp., Serratia spp., and Morganella morganii (ECSM), the prevalence of ESBL-producing isolates are increasing. However, there have been only a limited number of studies that have investigated the prevalence for ESBL-production in blood isolates of these organisms. MATERIALS AND METHODS: We performed a prospective observational study to evaluate the prevalence for ESBL production among ECSM blood isolates. All consecutive blood isolates in the Samsung Medical Center were included from Oct 2006 to Mar 2008. Antimicrobial susceptibility test was performed by broth microdilution method. ESBLs were confirmed by double-disk synergy test and ESBL phenotypes were determined by PCR. RESULTS: The 124 isolates (94 Enterobacter spp., 18 Citrobacter spp., 8 Serratia spp. and 4 Morganella spp.) were investigated. Among 124 ESCM isolates, 30 isolates (24.2%) showed ESBL-producing activity. Derepressed or partially derepressed AmpC mutants and derepressed AmpC mutants with ESBL production accounted for 36.3% (45/124) and 16.9% (21/124), respectively. Of ESBL producers, the most prevalent ESBL was SHV-12 (5/24, 20.8%). CONCLUSIONS: The prevalence of ESBL-producing isolates is high in Enterobacter spp., Serratia marcescens and Citrobacter spp. clinical isolates. It suggested that routine screening test for ESBLs among Enterobacteriacae blood isolates with inducible AmpC beta-lactamase should be needed.

A Case of Citrobacter braakii Sepsis Complicated with Hepatocellular Carcinoma

Citrobacter species is a gram-negative bacilli that can cause opportunistic infections in immunocompromised hosts. Citrobacter braakii refers to the genomospecies 6 of the Citrobacter freundii complex. There are no detailed studies on infections caused by this newly identified specific genetic species in Korea. We herein report a case of a patient with hepatocellular carcinoma who, after undergoing transcatheter arterial chemoembolization, developed biloma which later progressed to C.braakii sepsis and did not respond to treatment. To our knowledge, this is the first reported case in Korea on C. braakii infection resulting in septic shock in a patient with malignancy in Korea.