Surveillance of bacterial resistance in children aged 0-14 years from 2018 to 2022 / 中华儿科杂志

Objective: To understand the distribution and antimicrobial resistance of common bacteria from children aged 0-14 years from China Antimicrobial Resistance Surveillance System. Methods: Bacterial resistance data of 2 575 040 strains from children aged 0-14 years were extracted from the national bacterial resistance surveillance reports from October 2018 to September 2022 and resistance changes were further analyzed by comparing with all data in each year. Results: The total number of bacteria isolated from children in 2018-2022 ranged from 415 306-588 016 strains, accounted for 15.9% (514 193/3 234 372), 16.2% (572 107/3 528 471), 12.8% (415 306/3 249 123), 13.0% (485 418/3 743 027), and 12.2% (588 016/4 828 509), respectively. The proportions of gram-positive bacteria among children were 45.4% (233 456/514 193), 44.5% (254 869/572 107), 44.7% (185 756/415 306), 42.6% (206 903/485 418), and 41.7% (245 044/588 016), respectively. The top five isolates of gram-positive bacteria were Staphylococcus aureus (36.0%-38.8%), Streptococcus pneumoniae (27.1%-31.7%), Staphylococcus epidermidis (7.3%-9.3%), Enterococcus faecium (4.0%-4.8%), and Enterococcus faecium (2.5%-3.6%), and the top five isolates of gram-negative bacteria were Escherichia coli (21.8%-26.2%), Haemophilus influenzae (14.4%-26.4%), Klebsiella pneumoniae (10.1%-14.7%), Moraxella catarrhalis (7.3%-11.9%), and Pseudomonas aeruginosa (5.5%-6.8%). The bacteria from children aged 0-14 years commonly isolated from sputum samples (48.8%-57.0%). The prevalence of methicillin-resistant S. aureus was 28.7%-30.1%. The detection rates of vancomycin-resistant E. faecalis or E. faecium were 0.1%-0.3%. The proportions of non-cerebrospinal fluid-derived penicillin-resistant S. pneumoniae were 0.7%-1.6%. The prevalence of cefotaxime and (or) ceftriaxone-resistant E. coli and K. pneumoniae decreased were 43.7%-50.0% and 31.8%-42.7%, respectively. The resistant rates of E. coli to imipenem and meropenem were 1.2%-1.9% and 1.2%-2.0%, respectively, and the resistant rates of K. pneumoniae to imipenem and meropenem were 7.3%-10.1% and 8.2%-12.2%, respectively. About 6.6%-10.2% and 5.3%-9.6% of the P. aeruginosa isolates showed resistant to imipenem and meropenem, respectively, while 17.2%-24.0% and 19.0%-29.4% of the Acinetobacter baumannii isolates were resistant to imipenem and meropenem, respectively. Conclusions: There is no significant change in the composition of common clinical pathogens in children aged 0-14 years from 2018 to 2022. The prevalence of some resistant bacteria such as methicillin-resistant S. aureus and carbapenem-resistant Enterobacterales is decreasing. However, it is necessary to pay attention to antimicrobial resistance of bacteria from children and long-term monitoring of the prevalence of resistant bacteria should be conducted.

Clinical Characteristics and Risk Factors for 30-Day Mortality in Patients with Hematologic Diseases Infected by Carbapenem-Resistant Organisms / 中国实验血液学杂志

OBJECTIVE@#To explore the clinical characteristics of hospitalized patients with hematologic diseases complicated with carbapenem-resistant organisms (CRO) infection and analyze the risk factors of 30-day all-cause mortality.@*METHODS@#The clinical data and laboratory test data of 77 hospitalized patients with hematologic diseases complicated with CRO infection in department of hematology of the Third Hospital of Shanxi Medical University from January 2015 to December 2020 were retrospectively analysed, the risk factors of 30-day all-cause mortality after CRO infection were analyzed by multivariate logistic regression.@*RESULTS@#Among the total of 77 patients with hematologic diseases complicated with CRO infection, 29 died and 48 survived within 30 days of infection, with a case fatality rate of 37.66%. A total of 93 strains of CRO were isolated from these patients, of which Acinetobacter baumannii had the highest detection rate (25.81%, 24/93), followed by Pseudomonas aeruginosa (18.28%, 17/93). The lung was the most common site of CRO infection. The detected pathogens were highly resistant to carbapenems, and 64.52% (60/93) of the pathogens were resistant to imipenem with minimum inhibitory concentration (MIC)≥16 μg/ml. The results of the univariate analysis showed that albumin concentration <25 g/L (P =0.048), serum creatinine concentration≥120 μmol/L (P =0.023), age-adjusted Charlson comorbidity index (ACCI) (P =0.037) and primary treatments (supportive treatment, immunosuppressive therapy, chemotherapy, HSCT) (P =0.048) were significantly associated with 30-day all-cause mortality after infection. The results of multivariate logistic regression analysis showed that when CRO infection confirmed, albumin concentration <25 g/L (P =0.014, OR=6.171), serum creatinine concentration≥120 μmol/L (P =0.009, OR=10.867) were independent risk factors for 30-day mortality of patients with hematologic diseases complicated with CRO infection.@*CONCLUSION@#The mortality rate of CRO-infected patients with hematologic diseases is high. The detected pathogenic bacteria are highly resistant to imipenem. The albumin concentration <25 g/L and the serum creatinine concentration≥ 120 μmol/L at diagnosis of CRO infection were independent risk factors for 30-day mortality of the patients with hematologic diseases.

Osteomielitis por Klebsiella pneumoniae BLEE. Reporte de un caso y revisión de la literatura. / OSTEOMYELITIS DUE TO KLEBSIELLA PNEUMONIAE ESBL. REPORT OF A CASE AND LITERATURE REVIEW

Las betalactamasas de espectro extendido (BLEE) son enzimas producidas por bacilos gram negativos capaces de hidrolizar las cefalosporinas de amplio espectro y los monobactámicos. La mayoría pertenece a la familia de Enterobacteriae, tales como Klebsiella pneumoniae y Escherichia coli: Sin embargo, se asocian también con otras bacterias como Proteus, Serratia, Salmonella, Pseudomonas aeruginosa y Acinetobacter. Las enterobacterias productoras de carbapenemasas no sólo han sido aisladas en el ambiente hospitalario, sino que también provienen de la comunidad. Se presenta una paciente de sexo femenino con antecedentes de sida y osteomielitis secundaria a artritis séptica producida por una Klebsiella pneumoniae BLEE de la comunidad. Un tratamiento oportuno y eficaz puede evitar la opción quirúrgica, disminuyendo la morbimortalidad asociada con esta afección

Extended-spectrum beta-lactamases (ESBL) are enzymes produced by gram-negative rods capable of hydrolyzing broad-spectrum cephalosporins and monobactams. Most belong to the Enterobacteriae family, such as Klebsiella pneumoniae and Escherichia coli. However, they are also associated with other bacteria such as Proteus, Serratia, Salmonella, Pseudomonas aeruginosa and Acinetobacter. Carbapenemase-producing Enterobacteriaceae have not only been isolated from the hospital environment, but also from the community. We present a female patient with a history of AIDS and secondary osteomyelitis to septic arthritis caused by a community Klebsiella pneumoniae ESBL. It is concluded that a timely and effective treatment can avoids the surgical option, reducing the morbidity and mortality of this condition.

A case of late-onset Klebsiella oxytoca keratitis treated with topical imipenem after deep anterior lamellar keratoplasty / Caso de ceratite de início tardio por Klebsiella oxytoca tratado com imipenem tópico após ceratoplastia lamelar anterior profunda

ABSTRACT The aim of this study was to discuss a case of late-onset Klebsiella oxytoca keratitis after deep anterior lamellar keratoplasty and its treatment. A 21-year-old female patient presented with redness and effluence in the left eye at 5 months after uncomplicated deep anterior lamellar keratoplasty surgery. In the examination, a single suture was loosened in the superior nasal region and there was an infiltration area and epithelial defect in the graft and recipient bed junction in the area of the loose suture. Topical fortified vancomycin and fortified ceftazidime treatment was started empirically hourly, but there was insufficient response. After K. Oxytoca growth in a swab and suture culture taken from the patient, fortified vancomycin was replaced with fortified imipenem. It was observed that the infiltration area rapidly regressed and the epithelial defect was closed after fortified imipenem treatment. Fortified imipenem may be considered as an alternative treatment, especially in cases in which there is no response to treatment and culture growth is detected.(AU)

RESUMO O objetivo deste estudo é discutir um caso de ceratite tardia por Klebsiella oxytoca, após ceratoplastia lamelar anterior profunda, bem como seu tratamento. Uma paciente de 21 anos apresentou vermelhidão e efluxo no olho esquerdo 5 meses após cirurgia de ceratoplastia lamelar anterior profunda sem complicações. Ao exame, havia uma única sutura solta na região nasal superior e uma área de infiltração com defeito epitelial no enxerto e na junção com o leito receptor na área da sutura solta. Iniciou-se empiricamente um tratamento tópico com vancomicina e ceftazidima fortificada de hora em hora, porém com resposta insuficiente. Após o crescimento de K. oxytoca a partir de cultura de swab e sutura retirados da paciente, a vancomicina fortificada foi substituída por imipenem fortificado. Observou-se que a área de infiltração regrediu rapidamente e que o defeito epitelial foi fechado com o tratamento com imipenem fortificado. O imipenem fortificado pode ser considerado um tratamento alternativo, especialmente nos casos sem resposta ao tratamento e detecção de crescimento na cultura.(AU)

Pioderma gangrenoso ampollar como forma de presentación de leucemia mieloide agudo: informe de un caso / Acute myeloid leukemia presented in the form of bullous pyoderma gangrenosum: a case report

El pioderma gangrenoso ampollar es una variedad infrecuente de pioderma gangrenoso, que se asocia en el 50-70% de los casos con trastornos oncohematológicos. Se comunica el caso de una paciente de 59 años, que consultó por fiebre y ampollas purpúricas de rápida progresión, con compromiso cutáneo mucoso. Con sospecha de una enfermedad neutrofílica, ampollar, o infección por gérmenes oportunistas, se realizó biopsia de piel para estudio histopatológico, inmunofluorescencia directa y cultivo. Los cultivos y la inmunofluorescencia directa fueron negativos, y la anatomía patológica reveló un denso infiltrado inflamatorio con predominio neutrofílico en dermis. Ante el diagnóstico de pioderma gangrenoso ampollar, se realizó una punción-aspiración de médula ósea cuyo resultado fue compatible con leucemia mieloide aguda. Se instauró tratamiento con corticosteroides sistémicos, a pesar de lo cual la paciente evolucionó desfavorablemente y falleció a los 15 días de su ingreso hospitalario. Este caso ilustra la asociación de esta enfermedad cutánea con trastornos oncohematológicos y el mal pronóstico que esto implica a corto plazo. (AU)

Bullous pyoderma gangrenosum is an infrequent type of pyoderma gangrenosum, associated with onco hematological diseases in 50-70% of cases. We present the case of a 59-year-old patient with fever and mucocutaneous hemorrhagic bullous of rapid progression. A biopsy for histopathology, direct immunofluorescence (DIF) and skin culture was made, considering the possibility of neutrophilic dermatoses, bullous dermatosis or an opportunistic infection. The results of both the culture and the DIF were negative. The histopathological examination of the specimen revealed a dense dermal polymorphic infiltrate composed primarily of neutrophils. Considering bullous pyoderma gangrenosum as a potential diagnosis, a bone-marrow biopsy was performed. This study revealed an acute myeloid leukemia. Although systemic corticosteroid therapy was begun, the patient presented an unfavorable evolution that led to her death 15 days after her admission at the hospital. This case shows the association between bullous pyoderma gangrenosum and onco hematological diseases. In addition, it highlights the poor prognosis related to these diseases in the short term. (AU)

Resistência aos antimicrobianos e diversidade genética de variantes fenotípicas de Pseudomonas aeruginosa não sensíveis aos carbapenêmicos recuperadas de pacientes com fibrose cística com infecção pulmonar crônica: uma análise temporal / Antimicrobial resistance and genetic diversity of phenotypic variants of carbapenem non susceptible Pseudomonas aeruginosa recovered from patients with cystic fibrosis with chronic lung infection: a temporal analysis

Pseudomonas aeruginosa, bactéria ubíqua e versátil, pode se comportar como um patógeno oportunista, com ampla capacidade adaptativa, por múltiplos fatores de virulência e resistência. Como agente patogênico nas infecções pulmonares em pacientes com fibrose cística (FC), é motivo de prognóstico ruim, aumento de hospitalizações e altas taxas de morbimortalidade, sendo quase impossível a sua erradicação, ao evoluírem para a cronicidade. Globalmente, é notável o aumento nos índices de amostras não sensíveis aos carbapenêmicos e a múltiplos antimicrobianos, essenciais à terapêutica. Assim, avaliamos temporalmente a susceptibilidade aos antimicrobianos e a presença de amostras hipermutáveis (HPM) em P. aeruginosa de diferentes morfotipos, não sensíveis aos carbapenêmicos (PANSC), obtidas de pacientes FC com infecção pulmonar crônica, acompanhados em dois centros de referência no Rio de Janeiro. De 2007 a 2016, a análise retrospectiva, através dos resultados obtidos no teste de disco-difusão (TDD), permitiu selecionar amostras de PANSC incluídas neste trabalho. Usando os resultados obtidos no TDD, foi definida a susceptibilidade a outros antimicrobianos, bem como os fenótipos de resistência, multi-(MDR), extensivo-(XDR) e pandroga resistentes (PDR). Adicionalmente, determinou-se a concentração inibitória mínima (CIM) para imipenem (IPM), meropenem (MEM), doripenem (DOR) e polimixina (POL). Através de teste fenotípico, foi calculada a frequência de mutação espontânea e as amostras hipermutáveis foram caracterizadas. O sequenciamento de genoma total (SGT) foi realizado em seis amostras de diferentes morfotipos, incluindo uma variante fenotípica rara, a small colony variant (SCV). Essas amostras foram recuperadas em dois episódios de exacerbação do paciente. Foram investigadas a clonalidade, resistência a antimicrobianos e virulência. Das 143 amostras, de 18 pacientes (9 pediátricos e 9 adultos), os resultados do TDD apontaram taxas de não susceptibilidade superiores a 44% para gentamicina, amicacina, tobramicina e ciprofloxacina, e maiores de 30 % para POL. Pela determinação da CIM, quase a totalidade (96%) das amostras foram não sensíveis a IMP, seguidos de 56% para MEM e 44% para DOR. Analisando-se a distribuição dos valores da CIM50 e CIM90 nos dois grupos de pacientes, os valores para IMP foram maiores entre as amostras dos pacientes pediátricos, equivalendo a 32 µg/mL e 64 µg/mL, respectivamente. Cerca de 25%, 37% e 6% eram MDR, XDR e PDR, respectivamente. Aproximadamente 12% eram HPM, e mais da metade destas foram XDR. Após o SGT, as seis amostras, recuperadas do caso clínico foram classificadas em um novo sequence type (ST2744), com a presença de genes de resistência adquiridos blaPAO, blaOXA-50, aph(3')-Iib, fosA, catB7 e crpP, apresentando mutações em genes codificadores de porinas e bombas de efluxo. Entretanto, não foram observados marcadores genéticos clássicos exclusivos para os fenótipos SCV e HPM. Este é o primeiro relato de P. aeruginosa SCV na FC, no Brasil. A vigilância epidemiológica de P. aeruginosa é crucial para a conduta terapêutica, bem como para o sucesso da resposta do paciente e erradicação da infecção pulmonar, justificando o uso de técnicas fenotípicas e moleculares na detecção dos mecanismos de resistência e virulência desse microrganismo na FC.

Pseudomonas aeruginosa, a ubiquitous and versatile bacterium, can behave as an opportunistic pathogen, with strong adaptive capacity, due to multiple virulence and resistance factors. As a pulmonary infection pathogen in patients with cystic fibrosis (CF), it is related with poor prognosis, increased hospitalizations and high rates of morbidity and mortality, and the eradication is almost impossible, especially after chronicity. The increase rates of isolates non-susceptible to carbapenem and multiple antimicrobials, essentials to therapy, have been observed worldwide. Therefore, we assessed the antimicrobial susceptibility and the presence of hypermutability (HPM) in non-susceptible to carbapenem P. aeruginosa (PANSC) isolates from different morphotypes, obtained from CF patients with chronic pulmonary infection, followed at two reference centers in Rio de Janeiro. Using the results obtained by disk-diffusion test (DDT) between 2007 to 2016, we select 143 PANSC and susceptibility to other antimicrobials was defined, as well as the resistance phenotypes, multi- (MDR), extensive- (XDR) and pandrug resistant (PDR). Additionally, the minimum inhibitory concentration (MIC) for imipenem (IPM), meropenem (MEM), doripenem (DOR) and polymyxin (POL) was determined. Hypermutable isolates were characterized by determination of mutation frequency. Whole genome sequencing (WGS) was performed in six morphotypes isolates, including the small colony variant (SCV), a rare variant phenotype. These isolates were recovered in two exacerbation episodes. Clonality, antimicrobial resistance and virulence were investigated. Of the total (143 isolates) isolated from 18 patients (9 pediatric and 9 adults), non-susceptibility rates above than 44% for gentamicin, amikacin, tobramycin and ciprofloxacin, and more than 30% for POL were observed. Almost all (96%) of the isolates were non-susceptible to IPM by MIC determination, followed by 56% for MEM and 44% for DOR. MIC50 (32 µg/mL) and MIC90 (64 µg/mL) rates for IPM were higher among pediatric patient isolates and 25%, 37% and 6% were MDR, XDR and PDR, respectively. 12% of all isolates were classified as HPM and more than half were categorized as XDR. Using WGS, the six isolates recovered from the clinical case, were identified as a new sequence type (ST2744). Acquired resistance genes blaPAO, blaOXA-50, aph (3')-Iib, fosA, catB7 and crpP and mutations in encoding genes for porins and efflux pumps, was annotated. None exclusive classic genetic markers related to SCV and HPM phenotypes were not observed. This is the first Brazilian report of P. aeruginosa SCV in CF. Our results highlight the importance of epidemiological surveillance in P. aeruginosa. The application of phenotypic and molecular techniques to investigate resistance and virulence mechanisms, can contribute to therapeutic success in CF.

Expression analysis of drug-resistant gene (blaOXA-51) in carbapenemases producing Acinetobacter baumannii treated with imipenem/sulbactam combination

Drug-resistant Acinetobacter baumannii is a frightening reality. The aim of this study is to examine the expression profiles of blaOXA-51 gene in carbapenemases producing A. baumannii treated with imipenem/sulbactam combination. Carbapenemases producing A. baumannii was identified among clinical isolates of A. baumannii obtained from patients at Shahid Rajaee hospital, Gachsaran, Iran, from January to June 2018. Synergism testing of imipenem/sulbactam on carbapenemases producing A. baumannii was carried out by broth microdilution method. Eventually, the expression of blaOXA-51 gene was carried out to investigate the inhibitory properties of imipenem/sulbactam combination against carbapenemases producing A. baumannii using quantitative real time RT-PCR. Among A. baumannii isolates, 24% were carbapenemases producing A. baumannii. Imipenem/sulbactam combination revealed synergistic and partial synergistic effect for all tested isolates (FIC= 0.313-0.75). Finally, imipenem/sulbactam combination displayed significant down-regulation of blaOXA-51 gene in carbapenemases producing A. baumannii. Imipenem synergizes with sulbactam against carbapenemases producing A. baumannii by targeting of the blaOXA-51 gene.

Performance Evaluation of the Newly Developed BD Phoenix NMIC-500 Panel Using Clinical Isolates of Gram-Negative Bacilli

BACKGROUND: The emergence of carbapenem resistance among gram-negative bacilli (GNB), mediated by carbapenemase production, has necessitated the development of a simple and accurate device for detecting minimum inhibitory concentrations (MICs) and resistance mechanisms, especially carbapenemase production. We evaluated the performance of the BD Phoenix NMIC-500 panel (BD Diagnostic Systems, Sparks, MD, USA) for antimicrobial susceptibility testing (AST) and carbapenemase-producing organism (CPO) detection. METHODS: We used 450 non-duplicate clinical GNB isolates from six general hospitals in Korea (409 Enterobacteriaceae and 41 glucose non-fermenting bacilli [GNFB] isolates). AST for meropenem, imipenem, ertapenem, ceftazidime, and ceftazidime/avibactam, and CPO detection were performed using the Phoenix NMIC-500 panel. Broth microdilution was used as the reference method for AST. The rates of categorical agreement (CA), essential agreement (EA), minor error (mE), major error (ME), and very major error (VME) were calculated in each antimicrobial. In addition, PCR and sequencing were performed to evaluate the accuracy of CPO detection by the BD Phoenix NMIC-500 panel, and the rate of correct identification was calculated. RESULTS: The CA rates were >90% for all antimicrobials tested with the Enterobacteriaceae isolates, except for imipenem (87.2%). The GNFB CA rates ranged from 92.7% to 100% for all antimicrobials. The ME rates were 1.7% for Enterobacteriaceae and 0% for GNFB. The panel identified 97.2% (243/250) of the carbapenemase-producing isolates. CONCLUSIONS: The BD Phoenix NMIC-500 panel shows promise for AST and CPO detection.

Treatment of Mycobacterium Abscessus Pulmonary Disease / 대한내과학회지

Mycobacterium abscessus is the second most important pathogen in pulmonary disease caused by nontuberculous mycobacteria (NTM), following Mycobacterium avium. Mycobacterium abscessus is classified into three subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. abscessus subsp. bolletii. Mycobacterium abscessus is the most difficult to treat NTM due to its resistance to many antibiotics. Treatment should include an initial regimen of 2–3 injectable and oral antibiotics for several weeks or months, followed by inhaled amikacin and 1–3 oral antibiotics, depending on the subspecies and drug susceptibility patterns, including macrolide susceptibility. The continuation phase should be continued for a minimum of 12 months after culture conversion. Suitable injectable antibiotics include amikacin, imipenem, cefoxitin, and tigecycline, while oral antibiotics include macrolides (azithromycin or clarithromycin), clofazimine, linezolid, and moxifloxacin. Surgery can be a useful adjunctive therapy for some patients with refractory disease. However, the overall treatment prognosis is still unsatisfactory. Therefore, novel and more effective interventions are required for the treatment of M. abscessus pulmonary disease.

Change in the Annual Antibiotic Susceptibility of Escherichia coli in Community-Onset Urinary Tract Infection between 2008 and 2017 in a Tertiary Care Hospital in Korea

The susceptibility of Escherichia coli from community onset urinary tract infection (UTI) was evaluated by dividing community onset UTI into the simple community acquired-UTI (CA-UTI) and healthcare associated UTI (HCA-UTI) groups for a period of 10 years. The susceptibility of E. coli to most antibiotics, except amikacin and imipenem, continued to decrease. In the CA-UTI group, the susceptibility to cefotaxime was 88% in 2015, but rapidly decreased to 79.3% in 2017. The susceptibility to cefepime and piperacillin-tazobactam were 88.8% and 90.5% in 2017, respectively. In the HCA-UTI group, the susceptibility to most antibiotics markedly decreased to less than 60% by 2017. The incidence of ESBL-producing E. coli increased to 23.3% in the CA-UTI group in 2017.

Antimicrobial Susceptibility of Microorganisms Isolated from Patients with Intraabdominal Infection in Korea: a Multicenter Study

Necrolisis epidérmica tóxica en el curso de un síndrome hemofagocítico secundario a linfoma de Hodgkin: caso clínico / Toxic epidermal necrolysis during a hemophagocytic syndrome secondary to Hodgkin lymphoma: report of one case

Toxic epidermal necrolysis (TEN) is a lethal entity, characterized by extensive epidermal necrosis and multiorgan failure. Hemophagocytic syndrome (HFS) is also a rare and lethal syndrome characterized by hyperinflammation that leads to the appearance of fever, pancytopenia, organomegaly and hemophagocytosis. The concomitance of these diseases is extremely uncommon. We report a 38 years old female, who during the course of a HFS secondary to Hodgkin Lymphoma (HL), presented a TEN secondary to antibiotics. She was admitted due to a consumptive syndrome, lymphadenopathy, visceromegaly and severe pancytopenia. Laboratory and bone marrow tests confirmed HFS. Due to constant fever, imipenem was indicated. On the third day she started with pain and skin rash. She evolved with positive Nikolsky sign. Cutaneous biopsy was concordant with extensive TEN, which was managed with intravenous immunoglobulin and dexamethasone. A complete response and normalization of the blood count were achieved. Finally, the lymph node biopsy showed HL of mixed cellularity type, which was managed with 8 cycles of ABVD chemotherapy, achieving complete remission.

Performance of MALDI Biotyper for Species Identification of Carbapenem-Resistant Enterobacteriaceae by Media Types and Incubation Time

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.

Abrupt Increase in Rate of Imipenem Resistance in Acinetobacter baumannii Complex Strains Isolated from General Hospitals in Korea and Correlation With Carbapenem Administration During 2002–2013

No abstract available.

Epidemiology and treatment of antimicrobialresistant gram-negative bacteria in Korea

Antimicrobial resistance is becoming one of the greatest challenges to public health worldwide. Infections by antimicrobial-resistant organisms could result in the failure of treatment, increased medical costs, prolonged hospital stays, and an increased socioeconomic burden. Antimicrobial usage in Korea remains heavy, even after much effort to reduce their use. According to the Korean antimicrobial resistance surveillance system, the resistance rates of many bacteria are increasing. The resistance rate of Acinetobacter baumannii to imipenem in Korea increased to 85% in 2015, representing a major public threat. The reports of increased carbapenem resistance in Enterobacteriaceae are worrisome. More importantly, some carbapenem-resistant Enterobacteriaceae may result from the production of carbapenemases, which break down carbapenems. There are relatively few treatment options for extensively drug-resistant A. baumannii and carbapenem-resistant Enterobacteriaceae. Most reports are retrospective observational studies. Because there are little published data from randomized controlled trials, more data assessing antimicrobial treatment for extensively drug-resistant A. baumannii and carbapenem-resistant Enterobacteriaceae are needed to make treatment recommendations.

Prevalence, toxin gene profile, antibiotic resistance, and molecular characterization of Clostridium perfringens from diarrheic and non-diarrheic dogs in Korea

Clostridium perfringens causes diarrhea and other diseases in animals and humans. We investigated the prevalence, toxin gene profiles, and antibiotic resistance of C. perfringens isolated from diarrheic dogs (DD) and non-diarrheic dogs (ND) in two animal hospitals in Seoul, Korea. Fecal samples were collected from clinically DD (n = 49) and ND (n = 34). C. perfringens was isolated from 31 of 49 DD (63.3%) and 21 of 34 ND dogs (61.8%). All C. perfringens strains were positive for the α toxin gene, but not for the β, ε, or ι toxin genes; therefore, all strains were identified as type A C. perfringens. All isolates were cpe-negative, whereas the β2 toxin gene was identified in 83.9% and 61.9% of isolates from DD and ND, respectively. Most isolates were susceptible to ampicillin (94%), chloramphenicol (92%), metronidazole (100%), moxifloxacin (96%), and imipenem (100%). However, 25.0% and 21.2% of isolates were resistant to tetracycline and clindamycin, respectively. Molecular subtyping of the isolated strains was performed by using pulsed-field gel electrophoresis. Fifty-two isolates were classified into 48 pulsotypes based on more than 90% similarity of banding patterns. No notable differences were observed among the isolates from DD and ND.

Changes in Antimicrobial Susceptibility Pattern of Blood Isolates at a University Hospital in the Kyungnam area during 2005–2014 / 고신대학교의과대학학술지

OBJECTIVES: Blood culture is a one of the most important procedure for diagnosis and treatment of infectious disease, but distribution of pathogenic species and the antimicrobial susceptibility can be vary from pathogen, individual trait, regional or environmental features. In this study, we investigated the changes in frequency of occurrence and antimicrobial susceptibility pattern of blood isolates from 2005 to 2014. METHODS: Data of blood isolates from Kosin Gospel Hospital during 2005 to 2014 were analyzed retrospectively. Blood isolates were cultured for 5 days using BACTEC Plus Aerobic/F and BACTEC lytic/10 Anaerobic/F. Identification and antimicrobial susceptibility test was performed using VITEK 1 system, VITEK 2 XL, PHOENIX 100 and conventional method. RESULTS: 9,847 isolates were identified during 10 years. Among the isolates aerobic or falcutative anaerobic bacteria were isolated in 99.5% specimens, anaerobic were 0.1%, and fugi were 0.4%. Most commonly isolated bacteria were coagulase-negative Staphylococcus (CoNS) followed by Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae. Candida parapsilosis were most frequently isolated among fungi. The proportion of S. aureus, A. baumannii and E. faecium were increased, while Pseudomonas aeruginosa and Streptococcus pneumoniae decreased over decennium. Imipenem resistant K. pneumoniae were identified. Vancomycin resistant E. faecium and imipenem resistant A. baumannii were increased (7.1% in 2005 to 12.3% in 2014, 0% in 2005 to 55.6% in 2014, respectively). CONCLUSIONS: Over the last 10 year, CoNS were the most frequently isolated pathogen. Imipenem resistant K. pneumoniae was emerged. Vancomycin resistant E. faecium and imipenem resistant A. baumannii increased during this period.

Perfil de resistencia antimicrobiana en bacilos Gram negativos no fermentadores aislados en fuentes hídricas / Antimicrobial resistance profile in non-fermenting gram negative bacilli isolated in water resources

La amplia distribución de los bacilos gram negativos no fermentadores en medios ambientales como el agua y especies vegetales cobra importancia al ser reconocidos como agentes causales de enfermedades en pacientes inmunocomprometidos, de allí la relevancia del porque debemos conocer la prevalencia y perfil de susceptibilidad de estos microorganismos en ambientes no hospitalarios. Materiales y Métodos: Estudio transversal, realizado en muestras hídricas de fuentes naturales y artificiales de almacenamiento para el consumo humano en la ciudad de Bogotá y municipios aledaños. La identificación se realizó a través de pruebas IMVIC y el perfil de resistencia a través del método de kirby bauer o E-TEST®. Resultados: Se obtuvieron 42 muestras, 7 (16,6%) con aislamientos de interés: 3 (60%) Pseudomonas spp, 2 (20%) Acinetobacter spp, 1 (10%) Sphingomonas paucimobilis y 1 (10%) Pantoea spp. El 70% presento resistencia a la ceftriaxona, el 30% a cefoxitina, 20% a gentamicina, 10% a ciprofloxacina y 10% a piperacilina-tazobactam. No se presentó resistencia a imipenem. Conclusión: 5 de 7 aislamientos revelaron un BGNNF de importancia en infección en humanos, siendo importante la resistencia encontrada a la ceftriaxona.

The wide distribution of non-fermenting gram negative bacilli in environmental media such as water and plants becomes important as they are recognized a cause of diseases in immunocompromised patients, that’s the reason why we should to know the prevalence and the susceptibility profile of these microorganisms in non-hospital environments. Materials and Methods: Cross-sectional study done with samples of natural and artificial water storage for human consumption in the city of Bogotá and surrounding municipalities. The identification was made through IMVIC tests and the resistance profile through the kirby bauer or E-TEST® method. Results: 42 samples were obtained, 7 (16.6%) with isolates of interest: 3 (60%) Pseudomonas spp, 2 (20%) Acinetobacter spp, 1 (10%) Sphingomonas paucimobilis and 1 (10%) Pantoea spp. The 70% had resistance to ceftriaxone, 30% to cefoxitin, 20% to gentamicin, 10% to ciprofloxacin and 10% to piperacillin-tazobactam. No resistance to imipenem was shown. Conclusion: 5 of 7 isolates revealed a BGNNF of importance in infection in humans, with an important resistance to ceftriaxone.

Modulação in vitro da atividade antibiótica pelo óleo essencial dos frutos de Piper tuberculatum Jacq / Modulación in vitro de la actividad antibiótica por el aceite esencial de frutos de Piper tuberculatum Jacq / In vitro modulation of the antibiotic activity of essential oil from fruits of Piper tuberculatum Jacq

Introdução: Piper tuberculatum Jacq., popularmente conhecida como pimenta-longaou pimenta-d'Arda, é utilizada empiricamente no tratamento de doenças respiratórias (asma, bronquite e tosse) e digestivas (dores abdominais e diarreias). Na literatura é descrita com importantes atividades anti-inflamatória, antimicrobiana, antileucêmico e anti-helmíntica. Objetivos: avaliar a atividade moduladora do óleo essencial dos frutos de P. tuberculatum (OEPT) em associação com diferentes antibióticos frente à Staphylococcus aureus, Escherichia coli e Pseudomona aeruginosa. Metodos: Os frutos (frescos) de P. tuberculatum foram coletados em Barbalha/CE e submetidos à hidrodestilação em aparelho tipo Clevenger para ser extraído o óleo essencial, após a extração o óleo essencial foi tratado com sulfato de sódio anidro para eliminação da umidade residual. A avaliação da atividade antibacteriana e modulação (em resistência bacteriana) frente às cepas de S. aureus (SA358), E. coli (EC27) e P. aeruginosa (PA03) foram determinadas pelo método de microdiluição para identificar a concentração inibitória mínima (CIM), realizada em triplicata. CIM de ≤ 256 µg/mL foi considerado clinicamente relevante. Resultados: a atividade antibacteriana do OEPT exibiu um CIM de ≥ 1024 µg/mL contra as cepas de bactérias de padrão resistente a múltiplas drogas. Na avaliação da atividade moduladora, o OEPT antagonizou o efeito da amicacina contra E. coli e S. aureus, mas teve efeito sinérgico contra P. aeruginosa. Combinado com a getamicina o óleo exibiu antagonismo frente a E. coli, no entanto não apresentou resultado relevante contra S. aureas e P. aeruginosa. A associação do OEPT com o antibiótico imipenem resultou efeito mais relevante, apresentando sinergismo para todas as bactérias avaliadas, por outro lado, em associação com ciprofloxacino não apresentou efeito significante em relação ao controle. Conclusão: O OEPT apresentou uma melhor atividade quando associado ao imipenem frente todas as bactérias avaliadas, mostrando ser uma possível alternativa no desenvolvimento de novos fármacos com atividade antibacteriana advindos de produtos fitoterápicos(AU)

Introducción: Piper tuberculatum Jacq. popularmente conocida como pimenta-longa o pimenta-d'Arda, se utiliza empíricamente en el tratamiento de enfermedades respiratorias (asma, bronquitis y tos) y digestivas (dolor abdominal y diarrea). En la literatura es describe con importantes actividades antiinflamatorias, antimicrobianas, antileucémicas y antihelmínticas. Objetivo: evaluar la actividad moduladora de los aceites esenciales de frutos de P. tuberculatum (AEPT) en asociación con diferentes antibióticos contra Staphylococcus aureus, Escherichia coli y Pseudomona aeruginosa. Metodología: los frutos (frescos) de P. tuberculatum fueron recolectados en Barbalha/CE y sometidos a hidrodestilación en un equipo Clevenger, para extraer el aceite essencial (AEPT), el cual, una vez extraído, fue tratado con sulfato de sodio anhidro para eliminar la humedad residual. Se evaluó su actividad antibacteriana contra las cepas de S. aureus (SA358), E. coli (EC27) y P. aeruginosas (PA03). Empleando el método de microdilución se determinó la concentración inhibitoria mínima (CIM), con tres réplicas por cada tratamiento. Un valor de CIM ≤ 256 µg/mL se considera clínicamente relevante. Resultados: la actividad antibacteriana del AEPT exhibió una CIM ≥ 1024 µg/mL contra las cepas estándar de bacterias resistentes a múltiples fármacos. En efecto, la actividad AEPT antagoniza el efecto de amikacina contra E. coli y S. aureus, pero tenía un efecto sinérgico contra P. aeruginosa. Combinado con la getamicina el aceite exhibió antagonismo contra E. coli, sin embargo no presentó resultado relevante ante S. aureus y P. aeruginosa. La asociación de AEPT con el antibiótico imipenem resultó el efecto más relevante, mostrando sinergismo frente a todas las bacterias evaluadas. Por el contrario, en asociación con ciprofloxacina no mostró ningún efecto significativo con respecto al control. Conclusión: el AEPT presentó una mejor actividad cuando se asoció a imipenem, frente todas las bacterias evaluadas, demostrando ser una posible alternativa en el desarrollo de nuevos fármacos con actividad antimicrobiana, a partir de productos herbarios(AU)

Introduction: Piper tuberculatum Jacq., commonly known as pimenta-longa or pimenta-d'Arda, is empirically used to treat respiratory conditions (asthma, bronchitis and coughing) and digestive disorders (abdominal pain and diarrhea). Reference may be found in the literature to outstanding antiinflammatory, antimicrobial, antileukemic and antihelmintic activity. Objective: Evaluate the modulatory activity of essential oils from fruits of P. tuberculatum (AEPT) combined with various antibiotics againstStaphylococcus aureus, Escherichia coli and Pseudomona aeruginosa. Methods: Fresh fruits of P. tuberculatum were collected in Barbalha, CE, and subjected to hydrodistillation in a Clevenger set to extract the essential oil (AEPT). The oil extracted was then treated with anhydrous sodium sulfate to eliminate residual humidity. Antibacterial activity was evaluated against strains of S. aureus (SA358), E. coli (EC27) and P. aeruginosas (PA03). Minimum inhibitory concentration (MIC) was determined by the microdilution method, with three replications for each treatment. A MIC ≤ 256 µg/mL was considered to be clinically relevant. Results: Antibacterial activity of AEPT displayed a MIC of ≥1024 µg/mL against standard strains of multi-drug resistant bacteria. In fact, activity of AEPT antagonized the effect of amikacin against E. coli and S. aureus, but had a synergic effect against P. aeruginosa. Combined with gentamicin, the oil exhibited antagonism against E. coli, but no relevant result was obtained against S. aureus and P. aeruginosa. Combination of AEPT with the antibiotic imipenem had the most relevant effect, displaying synergism against all the bacteria evaluated. However, in combination with ciprofloxacin it did not show any significant effect with respect to the control. Conclusion: AEPT displayed better activity against all the bacteria evaluated when combined with imipenem, proving to be a possible alternative for the development of new herbal drugs with antimicrobial activity(AU)

Trends in Drug Resistance ofover a 10-year Period: Nationwide Data from the China Surveillance of Antimicrobial Resistance Program / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Acinetobacter baumannii has emerged as an important pathogen causing a variety of infections. Using data from the China Surveillance of Antimicrobial Resistance Program conducted biennially, we investigated the secular changes in the resistance of 2917 isolates of A. baumannii from 2004 to 2014 to differ antimicrobial agents.</p><p><b>METHODS</b>Pathogen samples were collected from 17 to 20 hospitals located in the eastern, central, and western regions of China. Minimum inhibitory concentrations (MICs) were determined by a 2-fold agar dilution method, and antimicrobial susceptibility was established using the 2014 Clinical Laboratory Standards Institute-approved breakpoints. Isolates not susceptible to all the tested aminoglycosides, fluoroquinolones, β-lactams, β-lactam/β-lactam inhibitors and carbapenems were defined as extensively drug resistant.</p><p><b>RESULTS</b>The rates of nonsusceptibility to common antimicrobial agents remained high (>65%) over the years with some fluctuations to certain agents. The prevalence of imipenem-resistant A. baumannii (IRAB) increased from 13.3% in 2004 to 70.5% in 2014 and that of extensively drug-resistant A. baumannii (XDRAB) increased from 11.1% in 2004 to 60.4% in 2014. The activity of tigecycline was stable with MIC90 ≤4 mg/L against A. baumannii from 2009 to 2014. Susceptibility to colistin remained high (97.0%) from 2009 to 2014. The prevalence of XDRAB increased in all the three surveillance regions over the years and was significantly higher in Intensive Care Unit (ICU) wards than non-ICU wards.</p><p><b>CONCLUSIONS</b>This longitudinal multicenter surveillance program revealed the nationwide emergence of A. baumannii in China and showed a significant increase in prevalence from 2004 to 2014. High levels of bacterial resistance were detected among samples collected from clinical settings in China, with IRAB and XDRAB being especially prevalent. This study will help to guide empirical therapy and identify at-risk groups requiring more intense interventional infection control measures, while also helping to focus surveillance efforts.</p>