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The Burkholderia cepacia complex (BCC) represents a group of bacteria that are gram-negative, aerobic, and non-fermenters. They are notorious for causing infections in vulnerable individuals, such as those with compromised immune systems. Examples are patients suffering from cystic fibrosis or chronic granulomatous disease. These bacteria are prevalent in diverse habitats, like soil and water. Over the last four decades, they have gained recognition as both emerging opportunistic pathogens and nosocomial threats. Managing BCC infections poses significant challenges due to their inherent resistance to numerous antibiotics, thus raising substantial concerns within clinical settings. Here, we present a case series of bacteremia, with BCC as the causative organism. The isolates showed a curious phenomenon of producing a violet pigment.
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The Acidaminococcus genus is a part of the normal flora in gastrointestinal tract. It is a strictly anaerob Gram-negative coccus that is rarely pathogenic. We report the case of a 58-year-old man, who presented to surgery department A of the Charles Nicolle hospital, complaining of a wide inflammatory lesion in the anterior abdominal wall evolving for two weeks. Patient's anamnestic data included smoking, hypertension, and diabetes mellitus with poor compliance. The patient underwent flattening with excision of necrotic tissues and surgical drainage using a DELBET blade. Empirical antibiotic therapy with imipenem 1gx3/d, teicoplanin 400 mg 1 inj x2/d and gentamicin 400 mg 1 inj/d was administered pending bacteriological results. The bacteriological examination of a sample of necrotic tissue, after 72 h of incubation at 37 °C in anaerobic atmosphere, was able to detect a Gram-negative coccus, that the VITEK2 ANC system identified as Actinomyces canis with an accuracy of 80%. Whole genome sequencing was subsequently performed, that identified Acidaminococcus sp. AM33-14BH and demonstrated the following resistance genes: cfxa, tet(X) and tet(Q). An antibiogram for anaerobes was performed showing that the strain was resistant to amoxicillin but sensitive to amoxicillin-clavulanic acid, piperacillin-tazobactam, ertapenem, imipenem, meropenem and rifampin. Patient's condition improved after treatment with imipenem for 2 weeks, followed by oral amoxicillin-clavulanic acid for 16 days.This work highlights the role of molecular biology in the diagnosis of infections caused by anaerobes. Although the Vitek 2 ANC card provides rapid and acceptable identification of the most common anaerobic bacteria, improvements are needed for the identification of bacteria in the genera Acidaminococcus and Actinomyces.
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PURPOSE: Candida albicans is the second most common cause of candidemia in Malaysia. The Clinical and Laboratory Standards Institute (CLSI) broth microdilution method is the gold standard for determining its minimum inhibitory concentration (MIC); however, it is laborious and time-consuming. This study was conducted to evaluate the usefulness of alternative methods, namely Sensititre YeastOne (SYO), VITEK 2 system, and E-test for determining the MIC of clinical C. albicans isolates. MATERIALS AND METHODS: The susceptibilities of 95 C. albicans isolates were compared between SYO, VITEK 2 system, and E-test with CLSI broth microdilution method. The categorical agreement (CA), essential agreement (EA), very major errors (VME), major errors (ME) and minor errors (MiE) were calculated. RESULTS: Our finding showed the CA varied for SYO from 96.8% to 100%, while the EA ranged from 91.6% to 100%. The SYO method showed 1.1% of VME and ME, and up to 3.2% of MiE. Next, the CA and EA ranges for the VITEK 2 system were 97.8%-100% and 23.2%-100%, respectively. In the VITEK 2 technique, 1.1% of VME were found. For the E-test, the CA varied from 83.2% to 100% while the EA ranged from 64.2% to 98.9%. The E-test method showed 1.1% of VME and up to 16.8% of MiE. CONCLUSIONS: In conclusion, SYO and VITEK 2 (except flucytosine) could be potential alternatives to the CLSI broth microdilution method in determining the MIC of C. albicans.
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Antifúngicos , Candida albicans , Pruebas de Sensibilidad Microbiana , Pruebas de Sensibilidad Microbiana/métodos , Pruebas de Sensibilidad Microbiana/normas , Candida albicans/efectos de los fármacos , Candida albicans/aislamiento & purificación , Humanos , Antifúngicos/farmacología , Candidiasis/microbiología , MalasiaRESUMEN
Reliable detection of mecA and mecC-mediated beta-lactam resistance using automated antimicrobial susceptibility test systems is critical for patient care. The aim of this study was to compare the performance of the new cefoxitin screen test (oxsf02n) on the Vitek 2 card (Vitek 2) and BD Phoenix PMC-100 Gram-Positive AST Panel (Phoenix) against the reference method for the detection of mecA (and mecC)-mediated beta-lactam resistance. Two hundred fifty clinical fresh and stock Staphylococcus spp. isolates were included. There were 120 mecA-positive, 10 mecC-positive, and 120 mecA and mecC-negative isolates. Cefoxitin screen and oxacillin tests were performed on Vitek 2 and Phoenix and by their respective reference methods (disk diffusion for the cefoxitin screen test and broth microdilution for oxacillin) for all isolates. PCR testing was also performed to confirm the presence of mecA and/or mecC genes. Results from each system were compared to the reference methods. Statistical hypotheses were evaluated both for Vitek 2 compared to the reference methods and Vitek 2 compared to the Phoenix. Compared to the reference method, the Vitek 2 cefoxitin screen test had 100% sensitivity/98% specificity and the Phoenix cefoxitin screen test had 84% sensitivity/100% specificity for the detection of mecA (and mecC)-mediated beta-lactam resistance. When the oxacillin test was combined with the cefoxitin screen for Vitek 2, the sensitivity and specificity were unchanged. However, when the oxacillin and cefoxitin screen tests were combined for the Phoenix, the sensitivity increased to 100% and the specificity remained unchanged (100%). When considering cefoxitin alone, the Vitek 2 screen test showed a higher sensitivity than the Phoenix for the detection of mecA and mecC-mediated beta-lactam resistance. However, currently, both systems use a combination of the cefoxitin and oxacillin tests to interpret the final result, and both reached a high level of performance when cefoxitin and oxacillin results were combined.IMPORTANCEThis research marks the inaugural evaluation of the revamped cefoxitin screen test version in Vitek 2, juxtaposing it against reference methods and a primary competitor BD Phoenix.
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Antibacterianos , Cefoxitina , Pruebas de Sensibilidad Microbiana , Cefoxitina/farmacología , Pruebas de Sensibilidad Microbiana/métodos , Antibacterianos/farmacología , Humanos , Proteínas Bacterianas/genética , Oxacilina/farmacología , Staphylococcus/efectos de los fármacos , Staphylococcus/genética , Resistencia betalactámica , Infecciones Estafilocócicas/microbiología , Proteínas de Unión a las Penicilinas/genéticaRESUMEN
INTRODUCTION: Candida auris is emerging as an important cause of candidemia and deep seated candidal infection. We compared the susceptibility results of bloodstream Candida auris isolates by Vitek 2 with Sensititre YeastOne (SYO) method. METHODS: Forty-seven C. auris blood stream isolates were simultaneously tested for AFST by Vitek 2 and SYO. RESULTS: All strains were resistant to Fluconazole. 25.5% isolates showed pan-azole resistance. In comparison with SYO, lower MICs for voriconazole were noted with Vitek 2 (VME rate 76.1%). All strains were sensitive to anidulafungin and micafungin by SYO. For micafungin, Vitek 2 demonstrated higher MICs and an ME rate of 23.5%. Susceptibility interpretation of caspofungin by SYO was challenged by development of 'Eagle effect' resulting in sensitivity of 28.2%. We studied the evolution of caspofungin 'Eagle effect' with SYO by serial hourly MIC readings and noted that paradoxical growth commenced at 21 hrs of incubation. Compared to SYO, Vitek 2 showed higher resistance rate to Amphotericin B with ME rate of 25.6%. CONCLUSION: Laboratories using commercial AFST systems for Candida auris need to be aware of the possibility of ME and VME for amphotericin B and voriconazole respectively with Vitek 2 and 'Eagle effect' for caspofungin with SYO.
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Antifúngicos , Candida auris , Pruebas de Sensibilidad Microbiana , Pruebas de Sensibilidad Microbiana/métodos , Antifúngicos/farmacología , Humanos , Candida auris/efectos de los fármacos , Candidemia/microbiología , Farmacorresistencia Fúngica , Equinocandinas/farmacología , Candidiasis/microbiología , Caspofungina/farmacología , Candida/efectos de los fármacos , Candida/aislamiento & purificaciónRESUMEN
Ochrobactrum anthropi is a non-fermenting, Gram-negative bacillus and an emerging opportunistic pathogen. We have isolated this organism from the blood cultures of two patients, a 53-year-old immunocompetent male presenting with an episode of mild fever post craniotomy and an 85-year-old male with chronic obstructive pulmonary disease (COPD) and urinary retention on an indwelling catheter. The organism was identified using VITEK 2 (bioMérieux, France). Both the isolates were resistant to most of the ß-lactams, including cephalosporins, and sensitive to quinolones, aminoglycosides, and carbapenems.
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PURPOSE: Burkholderia cepacia complex (Bcc) is a diverse group of environmental bacteria associated with opportunistic infections. The identification of Bcc using conventional methods poses challenges. Bcc infections are difficult to treat due to intrinsic antibiotic resistance. The study aimed to investigate the species distribution and antimicrobial susceptibility of clinical Bcc isolates. METHODS: A total of 153 Bcc isolates obtained from clinical samples were analysed. Species identification was carried out using automated methods, including MALDI-TOF MS and VITEK2. Antimicrobial susceptibility testing was performed using the disc diffusion method. RESULTS: Burkholderia cenocepacia (70.5%) emerged as the most prevalent species, followed by Burkholderia contaminans (9.8%) and Burkholderia cepacia (7.2%). Ventilator-associated pneumonia (38.6%) was the most common infection, followed by sepsis (28.1%). Co-existence of Bcc with other pathogens in many cases suggested potential co-infection scenarios. Antimicrobial susceptibility revealed that ceftazidime, co-trimoxazole and meropenem were the most effective drugs, while levofloxacin proved to be the least effective. Moderate susceptibility was noted to minocycline, with 4.6% of isolates exhibiting multi-drug resistance. CONCLUSION: This study provides valuable insights into the prevalence, clinical associations, and antibiotic susceptibility of Bcc in India. It highlights the importance of Bcc as a nosocomial pathogen, especially in vulnerable patient populations. The findings contribute to understanding Bcc infections, their distribution, and emphasize the necessity for accurate identification methods in clinical settings.
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Antibacterianos , Infecciones por Burkholderia , Complejo Burkholderia cepacia , Pruebas de Sensibilidad Microbiana , Centros de Atención Terciaria , Humanos , India/epidemiología , Infecciones por Burkholderia/microbiología , Complejo Burkholderia cepacia/efectos de los fármacos , Complejo Burkholderia cepacia/aislamiento & purificación , Complejo Burkholderia cepacia/clasificación , Antibacterianos/farmacología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adulto Joven , Adolescente , Anciano , Niño , Preescolar , Lactante , Neumonía Asociada al Ventilador/microbiología , Sepsis/microbiología , Anciano de 80 o más Años , Coinfección/microbiología , Ceftazidima/farmacologíaRESUMEN
BACKGROUND: Rapid antimicrobial susceptibility testing (AST) for bloodstream infections (BSIs) facilitates the optimization of antimicrobial therapy, preventing antimicrobial resistance and improving patient outcomes. QMAC-dRAST (QuantaMatrix Inc., Korea) is a rapid AST platform based on microfluidic chip technology that performs AST directly using positive blood culture broth (PBCB). This study evaluated the performance of QMAC-dRAST for Gram-negative bacteria using PBCB and subcultured colony isolates, comparing it with that of VITEK 2 (bioMérieux, France) using broth microdilution (BMD) as the reference method. METHODS: We included 141 Gram-negative blood culture isolates from patients with BSI and 12 carbapenemase-producing clinical isolates of Enterobacterales spiked into blood culture bottles. QMAC-dRAST performance was evaluated using PBCB and colony isolates, whereas VITEK 2 and BMD were tested only on colony isolates. RESULTS: For PBCB, QMAC-dRAST achieved 92.1% categorical agreement (CA), 95.3% essential agreement (EA), with 1.8% very major errors (VMEs), 3.5% major errors (MEs), and 5.2% minor errors (mEs). With colony isolates, it exhibited 92.5% CA and 95.1% EA, with 2.0% VMEs, 3.2% MEs, and 4.8% mEs. VITEK 2 showed 94.1% CA and 96.0% EA, with 4.3% VMEs, 0.4% MEs, and 4.3% mEs. QMAC-dRAST yielded elevated error rates for specific antimicrobial agents, with high VMEs for carbapenems and aminoglycosides. The median time to result for QMAC-dRAST was 5.9 h for PBCB samples and 6.1 h for subcultured colony isolates. CONCLUSIONS: The QMAC-dRAST system demonstrated considerable strengths and comparable performance to the VITEK 2 system; however, challenges were discerned with specific antimicrobial agents, underlining a necessity for improvement.
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Antibacterianos , Cultivo de Sangre , Bacterias Gramnegativas , Pruebas de Sensibilidad Microbiana , Pruebas de Sensibilidad Microbiana/métodos , Humanos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/aislamiento & purificación , Cultivo de Sangre/métodos , Antibacterianos/farmacologíaRESUMEN
INTRODUCTION: Colistin is the last resort treatment against resistant Gram-negative bacteria, necessitating reliable and rapid means for sensitivity testing of colistin. Automated systems like VITEK®2 are adopted to determine the minimum inhibitory concentration (MIC) due to easy usage. Broth microdilution (BMD) for colistin MIC was suggested by EUCAST and CLSI. OBJECTIVE: To compare and evaluate colistin MIC by BMD and VITEK®2 against Gram-negative organisms from the ICU in a tertiary care hospital. METHOD: Clinically significant organisms isolated from ICU patients were included. MIC was determined using BMD and VITEK®2. Very major error (VME), major error (ME), essential agreement (EA), categorical agreement (CA), positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity were analysed. RESULT: 533 isolates were obtained from blood (435,81.60%), respiratory samples (57,10.70%), pus and exudates (20,3.80%), urine (18,3.40%), and CSF (3,0.60%). The Enterobacterales were K. pneumoniae (185,34.70%) E. coli (73,13.70%) and E. cloacae (26,4.90%) while non-fermenters were A. baumannii (209,39.20%) and P. aeruginosa (40,7.50%). The VITEK®2 sensitivity was >99%; specificity ranged from 14.28 to 52.94%. PPV was 93.81% while NPV was 93.75%. VME ranged from 47 to 100% between isolates. ME was up to 20%. The highest VME was obtained in E. coli (100%). The total EA and CA observed were 68.5% and 99.79% respectively. CONCLUSION: Automated system VITEK®2 failed to detect the resistance in 32 (60%) isolates. The obtained VME and ME values were >3%, which is unacceptable as per the standard guidelines. EA of ≥90% wasn't obtained. Sensitivity for VITEK®2 was >99%, but had low specificity (14.28%). Hence, VITEK®2 is not reliable for colistin susceptibility testing.
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Antibacterianos , Colistina , Bacterias Gramnegativas , Infecciones por Bacterias Gramnegativas , Unidades de Cuidados Intensivos , Pruebas de Sensibilidad Microbiana , Centros de Atención Terciaria , Colistina/farmacología , Pruebas de Sensibilidad Microbiana/métodos , Humanos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/aislamiento & purificación , Antibacterianos/farmacología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/diagnóstico , Sensibilidad y EspecificidadRESUMEN
Although the Vitek 2 system is broadly used for antifungal susceptibility testing of Candida spp., its performance against Candida auris has been assessed using limited number of isolates recovered from restricted geographic areas. We therefore compared Vitek 2 system with the reference Clinical and Laboratory Standards Institute (CLSI) broth microdilution method using an international collection of 100 C. auris isolates belonging to different clades. The agreement ±1 twofold dilution between the two methods and the categorical agreement (CA) based on the Centers for Disease Control and Prevention's (CDC's) tentative resistance breakpoints and Vitek 2-specific wild-type upper limit values (WT-ULVs) were determined. The CLSI-Vitek 2 agreement was poor for 5-flucytosine (0%), fluconazole (16%), and amphotericin B (29%), and moderate for voriconazole (61%), micafungin (67%), and caspofungin (81%). Significant interpretation errors were recorded using the CDC breakpoints for amphotericin B (31% CA, 69% major errors; MaEs) and fluconazole (69% CA, 31% very major errors; VmEs), but not for echinocandins (99% CA, 1% MaEs for both micafungin and caspofungin) for which the Vitek 2 allowed correct categorization of echinocandin-resistant FKS1 mutant isolates. Discrepancies were reduced when the Vitek 2 WT-ULV of 16 mg/L for amphotericin B (98% CA, 2% MaEs) and of 4 mg/L for fluconazole (96% CA, 1% MaEs, 3% VmEs) were used. In conclusion, the Vitek 2 system performed well for echinocandin susceptibility testing of C .auris. Resistance to fluconazole was underestimated whereas resistance to amphotericin B was overestimated using the CDC breakpoints of ≥32 and ≥2 mg/L, respectively. Vitek 2 minimun inhibitory concentrations (MICs) >4 mg/L indicated resistance to fluconazole and Vitek 2 MICs ≤16 mg/L indicated non-resistance to amphotericin B.
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Anfotericina B , Fluconazol , Humanos , Fluconazol/farmacología , Anfotericina B/farmacología , Antifúngicos/farmacología , Candida auris , Micafungina , Caspofungina , Pruebas de Sensibilidad Microbiana , Equinocandinas/farmacologíaRESUMEN
Linezolid is an effective oxazolidinone antibiotic against multi resistant Gram-positive organisms. Linezolid resistance is an emerging problem and some controversy exists about the reliability of different phenotypic methods of linezolid susceptibility testing. Fifty isolates each of methicillin resistant S. aureus (MRSA) and Staphylococcus haemolyticus were tested for linezolid susceptibility using Kirby-Bauer disc diffusion, E-test, automated system VITEK2, Broth micro-dilution (reference method) and PCR for the cfr gene. Six resistant isolates were identified, three each in MRSA and S. haemolyticus, all carrying the cfr gene. E-test and VITEK2 were found to be more accurate than disc diffusion test.
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Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Linezolid/farmacología , Staphylococcus aureus Resistente a Meticilina/genética , Reproducibilidad de los Resultados , Antibacterianos/farmacología , Staphylococcus , Pruebas de Sensibilidad MicrobianaRESUMEN
Candida haemulonii complex (Candida haemulonii [I], Candida duobushaemulonii [II], and Candida haemulonii var. vulnera [III]) has become relevant in recent times, not so much because of a high incidence in human clinical sample cultures but because of its remarkable antifungal resistance. The objective of this study was to evaluate several methods for the identification of this uncommon species of Candida. Ten isolates of C. haemulonii were identified by biochemical and proteomic methods, and their antifungal susceptibility testing was performed by both commercial and reference methods. MALDI-TOF MS (Vitek MS and Vitek MS PRIME) and Vitek2 correctly identified these genera but API method did not. There was a good correlation between the commercial methods and the reference methods for the AST. In conclusion Vitek MS, Vitek MS PRIME, and Vitek2 systems, but not API32C, are reliable for identification of C. haemulonii complex. Furthermore, MALDI-TOF MS systems could identify to the subspecies level. Commercial methods for antifungal susceptibility testing are valid for the study of this species and confirm amphotericin B and to azole resistance.
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Antifúngicos , Saccharomycetales , Humanos , Antifúngicos/farmacología , Proteómica , Candida , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodosRESUMEN
INTRODUCTION: Candida auris is a notorious pathogen capable of forming biofilms on devices as well as host tissues, often culminating in infections. We evaluated characteristics of infections and the methods to diagnose C. auris over a period of three years in a tertiary care hospital. METHODS: Patients admitted between 2018 and 2020, who had candidemia due to C. auris were included in the study. Identification was performed using HiCrome™ Candida Differential Agar, Vitek 2 (BioMérieux, Inc., Marcy-l'Etoile, France) and MALDI-TOF, Vitek-MS. Identification was confirmed by detection of rDNA region covering part of 5.8S, entire of ITS2, and part of 28S by polymerase chain reaction (PCR). Biofilm formation was assessed by crystal violet staining. RESULTS: Presence of central line and broad spectrum antimicrobials were noted in all patients whereas total parenteral nutrition was given in 82.1% of these patients. Identification by Vitek2 v8.1 correlated with MALDI-TOF MS. PCR products of length 163 âbp were obtained in all isolates as visualized by agarose gel electrophoresis. The biofilm quantity measured as A560 of the twenty-eight C. auris isolates ranged from 0.16 to 0.80 compared to C. albicans. CONCLUSIONS: C. auris can be identified by PCR targeting specific rDNA region. Biofilm formation and quantification can be achieved by growing C. auris isolates in Mueller-Hinton broth over a duration of 48 âh.
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Candida auris , Violeta de Genciana , Humanos , Antifúngicos/uso terapéutico , Candida albicans , Reacción en Cadena de la Polimerasa , Biopelículas , ADN Ribosómico/genética , Pruebas de Sensibilidad MicrobianaRESUMEN
Introduction: The increasing antibiotic resistance like the advent of carbapenem resistant Enterobactarales (CRE), Carbapenem Resistant Acinetobacter baumanii (CRAB), and Carbapenem Resistant Pseudomonas aeruginosa (CRPA) has led to to the use of toxic and older drugs like colistin for these organisms. But worldwide there is an increase in resistance even to colistin mediated both by chromosomes and plasmids. This necessitates accurate detection of resistance. This is impeded by the unavailability of a user-friendly phenotypic methods for use in routine clinical microbiology practice. The present study attempts to evaluate two different methods - colistin broth disc elution and MIC detection by Vitek two in comparison to CLSI approved broth microdilution (BMD) for colistin for Enterobactarales, Pseudomonas aeruginosa , and Acinetobacter baumanii clinical isolates. Methods: Colistin susceptibility of 6013 carbapenem resistant isolates was determined by BMD, Colistin Broth Disc Elution (CBDE), and Vitek two methods and was interpreted as per CLSI guidelines. The MIC results of CBDE, Vitek two were compared with that of BMD and essential agreement (EA), categorical agreement (CA), sensitivity, specificity, very major error (VME), major error (ME) and Cohen's kappa (CK) was calculated. The presence of any plasmid-mediated colistin resistance (mcr-1, 2, 3, 4 and 5) was evaluated in all colistin-resistant isolates by conventional polymerase chain reaction. Results: Colistin resistance was found in 778 (12.9â%) strains among the carbapenem resistant isolates. Klebsiella pneumoniae had the highest (18.9â%) colistin resistance by the BMD method. MIC of Vitek two had sensitivity ranging from 78.2-84.8% and specificity of >92â%. There were 171 VMEs and 323 MEs by Vitek two method, much more than CLSI acceptable range. The highest percentage of errors was committed for Acinetobacter baumanii (27.8â% of VME and 7.9â% ME). On the other hand, the CBDE method performed well with EA, CA, VME and ME within acceptable range for all the organisms. The sensitivity of the CBDE method compared to gold standard BMD varied from 97.5-98.8â% for different strains with a specificity of more than 97.6â%. None of the isolated colistin resistant organisms harboured mcr plasmids. Conclusion: As BMD has many technical complexities, CBDE is the best viable alternative available for countries like India. A sensitive MIC reported by Vitek two needs to be carefully considered due high propensity for VMEs particularly for Klebsiella spp.
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Background: Food safety is an important subject that the global cheese industry increases awareness of. This urges these economic sectors to elevate the level of research to minimize cheese contamination with pathogenic bacteria, such as Salmonella. Aim: Based on these merits, this study was conducted to genotype Salmonella spp. isolated from cheese samples of local stores in Al-Diwaniyah City, Iraq. Methods: The study used 41 samples of local fresh unsalted white cheese in a selective-growth-based isolation of Salmonella. These isolates were confirmed utilizing a slide-agglutination (SA) test and VITEK® 2 system (V2S). Then, the isolates were subjected to conventional PCR and sequencing techniques that both targeted the 16S rRNA gene. For subtyping, the Salmonella isolates were subjected to a random amplified polymorphic DNA (RAPD)-PCR method. Results: The results of both SA and V2S revealed the presence of 14 (34.2%) isolates of Salmonella spp. in the cheese samples. The PCR confirmed 6 (42.9%) of these isolates, which further were defined with close nucleotide similarity (98.03%) and (97.88%) to different world isolates, such as Salmonella enterica subsp. Arizonae and Salmonella enterica subsp. enterica serovar Typhi, respectively. The RAPD-PCR findings showed different fragments for all the tested isolates. Conclusion: The present study indicates that the samples of the local fresh unsalted white cheese contain different Salmonella genotypes, which could be originated from different contamination sources.
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Queso , Salmonella enterica , Animales , Técnica del ADN Polimorfo Amplificado Aleatorio/veterinaria , Genotipo , Queso/microbiología , ARN Ribosómico 16S , Irak , Salmonella/genéticaRESUMEN
Infectious diseases that spread through the bloodstream, known as bloodstream infections (BSIs), are a major global health problem. Positive outcomes for patients with sepsis are typically the result of prompt treatment started after an early diagnosis of BSIs. In this study, we evaluated the capabilities of a portable electronic nose (E-Nose) to detect BSIs with two commonly isolated Gram-negative bacterial species, E. coli and K. pneumonia. One hundred and five blood samples were randomly collected for blood culture examinations using BACTEC and VITEK 2 system, and headspace analysis by an E-Nose from June to December 2021. Classification accuracy of E. coli, K. pneumonia, and negative controls was measured using principal component analysis, area under the receiver operating characteristic curve, sensitivity, and specificity analysis. After incubation for 24 h, cluster plots generated using principal component analysis demonstrated that E-Nose could accurately diagnose the presence of E. coli and K. pneumonia in BACTEC blood culture bottles with a sensitivity and specificity of 100% in just 120 s. The E-Nose method has been shown to be an immediate, precise, and cost-effective alternative to automated blood culture BACTEC and VITEK 2 systems for the fast detection of the causative bacterial pathogens of BSIs in clinical practice. Thus, patients with such Gram-negative bacteremia can have guided empirical antimicrobial therapy on the same day of BSIs diagnosis, which can be lifesaving.
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Bacteriemia , Neumonía , Sepsis , Humanos , Nariz Electrónica , Escherichia coli , Sepsis/diagnóstico , Bacteriemia/microbiología , Antibacterianos/uso terapéutico , Neumonía/tratamiento farmacológicoRESUMEN
Kocuria species are known to be opportunistic pathogens that cause infections in humans, especially immunocompromised hosts. However, reports of pediatric patients are limited. This retrospective study was designed to investigate the spectrum of infections in pediatric patients caused by Kocuria species. Thirty-six patients were enrolled; of these, 29 were infected by Kocuria kristinae, 4 by Kocuria roseus, 2 by Kocuria varians, and 1 by Kocruria rhizophila. Twenty-six patients were diagnosed with bloodstream infection; 6 had ventilator-associated pneumonia; and one each had a catheter-associated urinary tract infection, purulent meningitis, cholangitis, and empyema. Twenty-seven patients were immunocompromised or debilitating, had congenital abnormalities or fitted with indwelling devices. Nine patients were immunocompetent, 4 with early onset before 1 year of age. All Kocuria species were susceptible to lenezolid, vancomycin, and tigecycline; while showing frequent resistance to penicillin and oxacillin. Most cases were cured by administering appropriate antimicrobial agents. To our knowledge, this is the largest case series of pediatric patients with Kocuria species infection. We highlight Kocuria species should be considered as an underappreciated pathogen in pediatric patients.
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Antiinfecciosos , Sepsis , Humanos , Niño , Estudios Retrospectivos , Tigeciclina , VancomicinaRESUMEN
INTRODUCTION: Catheter-associated urinary tract infection (CAUTI) is the most common healthcare-associated infection which tends to cause increased length of morbidity, and mortality of patients, in addition to increased bacterial resistance to antibiotics. METHODOLOGY: In the present study, urinary catheters were collected from a 50-year-old woman suffering from malignancy, bedridden, and having urinary incontinence. These catheters were processed in laboratory for isolation of bacteria using standard procedures. RESULTS: Microbiological examination of the urinary catheters by biochemical, physiological, and VITEK 2 compact system revealed bacterial infection caused by Micrococcus lylae, a Gram-positive microorganism belonging to the family Micrococcacea. These Gram-positive bacteria were found to be susceptible to streptomycin, erythromycin, cefotaxime, neomycin, kanamycin, vancomycin, azithromycin, chloramphenicol, and tetracycline. Bacterial species were confirmed using 16s rRNA sequencing. CONCLUSIONS: The sequences were found to have 99% similarity with Micrococcus lylae. This is the first report of isolation of Micrococcus lylae from the urinary catheter.
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Infecciones Bacterianas , Neoplasias , Infecciones Urinarias , Femenino , Humanos , Persona de Mediana Edad , Catéteres Urinarios , ARN Ribosómico 16S/genética , Antibacterianos/farmacología , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/microbiologíaRESUMEN
Skin flora bacteria, such as Cutibacterium acnes , are the predominant contaminants of blood products used for transfusion. Platelet concentrates (PCs), a therapeutic product used to treat patients with platelet deficiencies, are stored at ambient temperature under agitation, providing ideal conditions for bacterial proliferation. At Canadian Blood Services, PCs are screened for microbial contamination using the automated BACT/ALERT culture system. Positive cultures are processed and contaminating organisms are identified using the VITEK 2 system. Over a period of approximately 2 years, several PC isolates were identified as Atopobium vaginae to a high level of confidence. However, since A. vaginae is associated with bacterial vaginosis and is not a common PC contaminant, a retrospective investigation revealed that in all cases C. acnes was misidentified as A. vaginae . Our investigation demonstrated that the media type used to grow PC bacterial isolates can have a significant impact on the results obtained on the VITEK 2 system. Furthermore, other identification methods such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALD-TOF MS) and PCR amplification of the 16S RNA gene were only partially successful in the identification of C. acnes . Therefore, our findings support a multiphasic approach when PC isolates are identified as A. vaginae by the VITEK 2 system for proper identification of C. acnes using macroscopic, microscopic and other biochemical analyses.
RESUMEN
Aerobic vaginitis (AV) is a vaginal infectious condition characterized by abnormal vaginal discharge, high inflammatory response, signs of epithelial atrophy, an increase in aerobic bacteria of intestinal origin and a decrease in the normal flora, especially Lactobacillus spp.. It is one of the most common reproductive tract infections among women. This study aimed to analyze the antimicrobial susceptibility levels of the dominant bacterial species found in the vaginae of women infected with AV. A total of 89 high vaginal swabs (HVS) were collected from women aged (18-50) years old attending some hospitals and private gynaecology clinics in Baghdad City. All obtained swabs were cultured on different culture media, and the primary diagnosis was performed according to standard laboratory diagnosis protocols. To confirm the diagnosis and to determine the antibiotic susceptibility profile of bacterial isolates, VITEK 2 Compact Automated System GP and GN colourimetric identification cards and AST GN and AST GP cards were used according to Manufacturer Company constructions (BioMérieux / France). Out of 89swabs, ninety-five pathogenic strains were obtained, including 62 isolates (65.2%), Grampositive and 33 isolates (34.7%), Gram-negative bacteria. Staphylococcus spp. (46.3%) The most represented active strain was Escherichia coli (15.7%). All Gram-positive bacterial strains displayed the highest resistance rates (100%) toward penicillins and cephalosporins, while the highest sensitivity rates were toward daptomycin, followed by vancomycin and gentamicin (P=0.001). Gram-negative bacteria displayed the highest resistance rates toward penicillins, beta-lactam combination, monobactam and cephalosporins, while the highest sensitivity rates were toward amikacin followed by imipenem meropenem and gentamicin (P=0.001). It is worth mentioning that Gram-positive bacteria showed 100% sensitivity toward tigecycline. Thirty-eight (40 %) of all obtained bacterial strains were extensively drug-resistant XDR, 57 (60%) were multidrug resistance MDR and no pan-drug resistance PDR was reported. Gram-positive bacteria include 21% XDR and 44.2% MDR strains, while Gram-negative bacteria include 18.9% XDR and 15.7% MDR strains.