SeptiFast for diagnosis of sepsis in severely ill patients from a Brazilian hospital

Objective To test and validate a multiplex real-time polymerase chain reaction method for bloodstream infections, as well as to compare the results with conventional blood culture.Methods A total of 114 consecutive patients with clinical evidence of sepsis were submitted to blood culture and LightCycler™ SeptiFast tests.Results More positive specimens (23; 20.2%) were detected using the LightCycler™ SeptiFast than the blood culture (17; 14.9%), with an agreement of 86.8%. Discordant results were seen in four patients positive only to blood culture, ten positive only to LightCycler™ SeptiFast and one to different pathogens found by each test. Infections with microorganisms detected only using blood culture reassured the need to perform both tests. The mean time to results for blood culture was 5 days for negative and 3.5 days for positive results. LightCycler™ SeptiFast results were achieved in less than 8 hours.Conclusion LightCycler™ SeptiFast showed a high potential as a test to be carried out concomitantly with blood culture for sepsis diagnosis in severely ill patients. This test allowed a faster diagnosis of bacterial and fungal infections that helped to reduce hospital stay and to control the use of antibiotics. LightCycler™ SeptiFast can also eventually detect microorganism and infections that are hardly detected by blood culture, especiallyCandidanon-albicans infections.

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Application of High-Resolution Melting PCR to Detect the Genomic Fungal ITS 2 Region

Laboratory Medicine ◽

10.1093/labmed/lmz034 ◽

2019 ◽

Vol 51 (1) ◽

pp. 66-73

Author(s):

Nada N Nawar ◽

Iman K Behiry ◽

Reham H A Yousef ◽

Mohamed A Emara

Keyword(s):

High Resolution ◽

Blood Culture ◽

Predictive Value ◽

High Resolution Melting ◽

Fungal Infections ◽

Fungal Species ◽

Candida Krusei ◽

Chain Reaction ◽

Polymerase Chain ◽

Positive Results

AbstractBackgroundInvasive fungal infections (IFIs) are a main cause of morbidity and mortality. High-resolution melting polymerase chain reaction (HRM PCR) is promising for the identification of fungal species via the detection of internal transcribed spacer 2 (ITS2).ObjectivesTo assess the sensitivity and specificity of HRM PCR in diagnosing IFIs, compared with blood culture.MethodsOur study included 100 patients who were suspected of having IFIs; we analyzed their specimens via blood culture and HRM PCR.ResultsBlood culture results were positive in 57 cases and negative in 43 cases. HRM PCR results were positive in 14 cases and negative in 86 cases. The 14 cases with positive results included 4 with Candida tropicalis, 4 with Candida glabrata, and 6 with Candida krusei. HRM PCR sensitivity was 24.6%, specificity was 100%, positive predictive value (PPV) was 100%, and negative predictive value (NPV) was 50%.ConclusionsHRM PCR is specific but not sensitive. Blood culture is more sensitive and cannot be replaced by HRM PCR.

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Validation of polymerase chain reaction in experimental sepsis diagnosis beyond blood culture

Critical Care ◽

10.1186/cc7080 ◽

2008 ◽

Vol 12 (Suppl 5) ◽

pp. P47

Author(s):

Marcello Ruiz-Silva ◽

Derci Sa-Filho ◽

Marcos Caseiro ◽

Ivan Koh

Keyword(s):

Polymerase Chain Reaction ◽

Blood Culture ◽

Experimental Sepsis ◽

Chain Reaction ◽

Sepsis Diagnosis ◽

Polymerase Chain

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Reduced susceptibility to daptomycin in methicillin-resistant Staphylococcus aureus isolated from catheter-related bloodstream infections

10.21203/rs.3.rs-970680/v1 ◽

2021 ◽

Author(s):

Sho Ohyatsu ◽

Tomoyuki Nariyama ◽

Kotaro Matsumoto ◽

Yuki Moritoki ◽

Kentaro Kikuchi

Keyword(s):

Staphylococcus Aureus ◽

Blood Culture ◽

Drug Treatment ◽

Methicillin Resistant Staphylococcus Aureus ◽

Bloodstream Infections ◽

High Dose ◽

Methicillin Resistant ◽

Treatment Methods ◽

History Of ◽

The Mean

Abstract Background The appearance of reduced susceptibility to daptomycin in methicillin-resistant Staphylococcus aureus (MRSA) has recently been reported. It is unclear how likely MRSA involved in catheter-related bloodstream infections (CRBSI) is to dampen susceptibility to daptomycin. We investigated the minimum inhibitory concentrations (MIC) of daptomycin in MRSA isolated from the blood of patients with CRBSI and examined how it was affected by previous anti-MRSA drug treatment. Methods A total of 115 patients whose blood culture samples were found to contain MRSA were enrolled in this study. The MIC of daptomycin and vancomycin and whether the subjects had a history of anti-MRSA drug treatment were investigated and compared between the CRBSI and non-CRBSI groups. Results The mean MIC of daptomycin was significantly higher for the 46 CRBSI-related MRSA isolates than for the 69 non-CRBSI-related MRSA isolates (0.78 vs. 0.33, respectively; p<0.0001). Among the CRBSI-related MRSA isolates, those collected from patients with a history of anti-MRSA drug treatment had significantly higher MIC (1.27 vs. 0.53, respectively; p <0.01). During treatment, MRSA was detected again in 10 CRBSI and 4 non-CRBSI patients, and all of the CRBSI-related MRSA isolates exhibited 1-2 log2 increases in their daptomycin MIC. Conclusions It is considered that when MRSA in catheter biofilms is exposed to anti-MRSA drugs, strains with reduced susceptibility to daptomycin are able to survive and disperse into the blood. Catheters should be removed if an MRSA-induced CRBSI is suspected. Further study of whether high-dose daptomycin treatment is effective when catheters cannot be immediately removed is needed.

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Significance of a polymerase chain reaction method in the detection of Clostridioides difficile

Revista Española de Quimioterapia ◽

10.37201/req/010.2020 ◽

2021 ◽

Vol 34 (2) ◽

pp. 141-144

Author(s):

Jerónimo Jaqueti Aroca ◽

Laura M. Molina Esteban ◽

Isabel García-Arata ◽

Jesús García-Martínez ◽

Isabel Cano De Torres ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Rapid Test ◽

Polymerase Chain Reaction Method ◽

Nucleic Acid Amplification ◽

Confirmatory Test ◽

Chain Reaction ◽

Clostridioides Difficile ◽

Toxigenic Culture ◽

Polymerase Chain ◽

Positive Results

Objectives. Clostridioides difficile (CD) is the most common cause of nosocomial diarrhea. Detection of CD toxin in patients’ faecal samples is the traditional rapid method for the diagnosis of CD infection. Various testing algorithms have been proposed: an initial screening test using a rapid test, and a confirmatory test (cytotoxicity neutralization assay, toxigenic culture, nucleic acid amplification test) for discordant results. The aim of this study was to evaluate the effectiveness of a two-step algorithm using an immunochromatographic test followed of a polymerase chain reaction (PCR). Material and methods. The specimens have been tested according to the following schedule: 1) Step one: All samples were tested for detection of glutamate dehydrogenase antigen (GDH) and toxin A/B using the C. diff QUIK CHEK Complete test. All GDH and toxins positive results were considered CD positives; 2) Step two: When the results were discrepant (only GDH+ or toxins+), the samples were confirmed using the PCR test BD MAX Cdiff. All PCR positive results were considered CD positives. Results. A total of 2,138 specimens were initially tested. 139 were positive for GDH and toxins. 160 discrepant results (148 GDH+ and 12 toxins+) were tested by PCR, 117 were positive (107/148 GDH+ and 10/12 toxins+). Conclusions. The implementation of a PCR method showed an increase de 117 positive results (73.1% of discrepant). Considering the sensitivity of C.diff QUIK CHEK (instructions of manufacturer), the GDH discrepant results may be false negatives, y the samples PCR and toxins positives may be real positives results.

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Comparison of results obtained by widal agglutination test & polymerase chain reaction among clinically suspected typhoid fever cases

Bangladesh Journal of Physiology and Pharmacology ◽

10.3329/bjpp.v30i2.22683 ◽

2015 ◽

Vol 30 (2) ◽

pp. 46-50

Author(s):

Shafinaz Khan ◽

Md Ruhul Amin Miah ◽

Shammin Haque ◽

Chowdhury Rafia Naheen

Keyword(s):

Polymerase Chain Reaction ◽

Blood Culture ◽

Typhoid Fever ◽

False Negative ◽

Salmonella Typhi ◽

Widal Test ◽

Chain Reaction ◽

Polymerase Chain ◽

Positive Results ◽

Prior Antibiotic Treatment

The diagnosis of typhoid fever currently depends on isolation of Salmonella Typhi from blood. The sensitivity of blood culture is very low due to prior antibiotic treatment which is a common practice in Bangladesh. The sensitivity of blood culture also decreases at later stage of the disease. Widal test is the most utilized test in Bangladesh next to blood culture because it is inexpensive, less invasive. But the result of the test is controversial due to false negative & false positive results in some cases. In this study, a recently introduced polymerase chain reaction-based technique (which has 100% specificity for S. Typhi) was compared with widal test among 80 clinically suspected typhoid fever cases. Among 80 cases, the respective figures of positivity for PCR & widal test were 70% & 43.75% respectively. It can be concluded that PCR based technique is more sensitive & much superior to widal for diagnosis of typhoid fever. DOI: http://dx.doi.org/10.3329/bjpp.v30i2.22683 Bangladesh J Physiol Pharmacol 2014; 30(2): 46-50

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Comparison of Candida Polymerase Chain Reaction Method and Blood Culture in Patients with High Risk of Candidemia in Intensive Care Unit

Mikrobiyoloji Bulteni ◽

10.5578/mb.20219708 ◽

2021 ◽

Vol 55 (4) ◽

pp. 568-579

Author(s):

Tuğçe Şimşek Bozok ◽

Ferit Kuşcu ◽

Taylan Bozok ◽

Süheyla Kömür ◽

Aslıhan Candevir ◽

...

Keyword(s):

Intensive Care Unit ◽

Polymerase Chain Reaction ◽

Intensive Care ◽

High Risk ◽

Blood Culture ◽

Polymerase Chain Reaction Method ◽

Chain Reaction ◽

Reaction Method ◽

Polymerase Chain

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Viral Infectivity in Patients Undergoing Tracheotomy With COVID-19: A Preliminary Study

Otolaryngology ◽

10.1177/01945998211004255 ◽

2021 ◽

pp. 019459982110042

Author(s):

Manish M. George ◽

Charlotte J. McIntyre ◽

Jie Zhou ◽

Ruthiran Kugathasan ◽

Dora C. Amos ◽

...

Keyword(s):

Prospective Observational Study ◽

Live Virus ◽

Reverse Transcription Pcr ◽

Surgical Tracheotomy ◽

Antibody Titers ◽

Tracheal Tissue ◽

The Mean ◽

Preliminary Study ◽

Polymerase Chain ◽

Positive Results

Objective To establish the presence of live virus and its association with polymerase chain reaction (PCR) positivity and antibody status in patients with COVID-19 undergoing tracheotomy. Study Design Prospective observational study. Setting Single institution across 3 hospital sites during the first wave of the COVID-19 pandemic. Methods Patients who were intubated for respiratory wean tracheotomy underwent SARS-CoV-2 PCR nasal, throat, and endotracheal tube swabs at the time of the procedure. These were assessed via quantitative real-time reverse transcription PCR. The tracheal tissue excised during the tracheotomy was cultured for SARS-CoV-2 with Vero E6 and Caco2 cells. Serum was assessed for antibody titers against SARS-CoV-2 via neutralization assays. Results Thirty-seven patients were included in this study. The mean number of days intubated prior to undergoing surgical tracheotomy was 27.8. At the time of the surgical tracheotomy, PCR swab testing yielded 8 positive results, but none of the 35 individuals who underwent tissue culture were positive for SARS-CoV-2. All 18 patients who had serum sampling demonstrated neutralization antibodies, with a minimum titer of 1:80. Conclusion In our series, irrespective of positive PCR swab, the likelihood of infectivity during tracheotomy remains low given negative tracheal tissue cultures. While our results do not undermine national and international guidance on tracheotomy after day 10 of intubation, given the length of time to procedure in our data, infectivity at 10 days cannot be excluded. We do however suggest that a preoperative negative PCR swab not be a prerequisite and that antibody titer levels may serve as a useful adjunct for assessment of infectivity.

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Multiplex Polymerase chain reaction to diagnose bloodstream infections in patients after cardiothoracic surgery

10.21203/rs.2.137/v1 ◽

2018 ◽

Author(s):

Kevin Pilarczyk ◽

Peter-Michael Rath ◽

Jörg Steinmann ◽

Matthias Thielmann ◽

Maximillian Dürbeck ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Cardiac Surgery ◽

Blood Culture ◽

Real Time ◽

Multiplex Polymerase Chain Reaction ◽

Bloodstream Infections ◽

Chain Reaction ◽

Blood Samples ◽

Gram Negative ◽

Polymerase Chain

Abstract Background: Sepsis and other infectious complications are major causes of mortality and morbidity in patients after cardiac surgery. Whereas blood culture (BC) as the current diagnostic gold standard suffers from low sensitivity as well as a reporting delay of approximately 48–72 h, polymerase chain reaction (PCR) based technologies might offer a fast and reliable alternative for detection of bloodstream infections (BSI). The aim of this study was to compare the performance of real time multiplex-PCR “SeptiFast” (SF), a real-time multiplex PCR assay, with conventional BC testing in patients after cardiac surgery. Methods: 279 blood samples from 168 individuals with suspected BSI were analyzed by SF and BC. Receiver operating characteristic (ROC) curves were generated to determine the accuracy of clinical and laboratory information for the prediction of positive SF results. Results: Excluding results attributable to contaminants, 14.7% (n = 41) of blood samples were positive using SF and 17.2% (n=49) using conventional BC (p= n.s.). In six samples, SF detected more than one pathogen. Among the 47 microorganisms identified by SF, only 11 (23.4%) could be confirmed by BC. SF identified a significantly higher number of Gram-negative bacteria than BC (28 vs. 12, χ2=7.97, p=0.005). The combination of BC and SF significantly increased the number of detected microorganism, including fungi, when compared to BC alone (86 vs. 49, χ2=13.51, p<0.001). C-reactive protein (CRP) (21.7±11.41 vs. 16.0±16.9 mg/dl, p=0.009), procalcitonin (PCT) (28.7±70.9 vs. 11.5±30.4 ng/dl, p=0.015) as well as interleukin 6 (IL 6) (932.3±1306.7 vs. 313.3±686.6 pg/ml, p=0.010) was significantly higher in patients with a positive SF result. In addition, incidence of severe acute kidney injury (AKI) was higher in SF positive than in SF negative patients (31/42 [76%] vs. 125/237 [53%], p=0.01). Using ROC analysis, IL-6 (AUC 0.836) as well as CRP (AUC 0.804), but not PCT showed the best predictive values for positive SF results. Microbiological diagnostic information gained through SF led to 8 therapy adaptations. Conclusion: The real time PCR-based SF test might represent a valuable addition to the traditional BC method for rapid etiologic diagnosis of BSI in patients after cardiothoracic surgery. This powerful method furthermore applies in particular for individuals with fungal infections, Gram-negative bacteremia, AKI and/or elevated CRP and IL-6-concentration. However, due to the low performance in detecting Gram-positive pathogens and the inability to determine antibiotic susceptibility, it should always be used in combination with BC. [1] Key words: Blood stream infection, blood culture, real time multiplex Polymerase Chain Reaction

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Evaluation of BACTEC MYCO/F Lytic Medium for Recovery of Mycobacteria and Fungi from Blood

Journal of Clinical Microbiology ◽

10.1128/jcm.36.5.1176-1179.1998 ◽

1998 ◽

Vol 36 (5) ◽

pp. 1176-1179 ◽

Cited By ~ 28

Author(s):

Rebecca T. Waite ◽

Gail L. Woods

Keyword(s):

Blood Culture ◽

Culture System ◽

Histoplasma Capsulatum ◽

Mycobacterium Kansasii ◽

Fungal Isolation ◽

Blood Culture System ◽

Valid Assessment ◽

The Mean ◽

Time To Detection ◽

Mean Time

The reliability of MYCO/F Lytic medium in the BACTEC 9240 blood culture system was evaluated by comparing its performance to that of the Isolator system for the recovery of fungi and to that of the ESP II system for the recovery of mycobacteria. Of 717 specimens of blood cultured for fungi, 24 were positive; 12 samples were positive with both systems, 7 samples were positive with the Isolator system only, and 5 samples were positive with MYCO/F Lytic medium only. Fourteen samples grew Histoplasma capsulatum; both systems detectedH. capsulatum in seven samples but the Isolator system alone detected H. capsulatum in seven samples. The mean times to the detection of H. capsulatum were 8 days (range, 4 to 13 days) for MYCO/F Lytic medium and 9 days (range, 6 to 18 days) for the Isolator system; the mean times to identification were 20 days (range, 15 to 24 days) for isolates recovered with MYCO/F Lytic medium and 11 days (range, 6 to 18 days) for those recovered with the Isolator system (P < 0.05). Cryptococcus neoformans was isolated from 10 fungal cultures; five isolates grew in both systems, and five isolates grew in MYCO/F Lytic medium only. The mean times to detection of C. neoformans were 4 days (range, 2 to 6 days) for MYCO/F Lytic medium and 7 days (range, 5 to 7 days) for the Isolator system (P < 0.05); the mean times to identification were 15 days (range, 7 to 27 days) for isolates recovered with MYCO/F Lytic medium and 8 days (range, 7 to 11 days) for those recovered with the Isolator system. Of the 687 samples of blood cultured for mycobacteria, 64 blood samples from 42 patients grew mycobacteria (58 grew Mycobacterium avium complex, 4 grew Mycobacterium kansasii, and 2 grew Mycobacterium tuberculosis); 42 isolates were recovered with both systems, 18 were isolated with MYCO/F medium only, and 4 were isolated with the ESP II system only alone (P < 0.05). The mean time to detection of mycobacteria with MYCO/F Lytic medium was 14 days, whereas it was 17 days with the ESP II system (P < 0.05). In summary, the combination of MYCO/F Lytic medium and the BACTEC 9240 instrument is an excellent blood culture system for the growth and detection of mycobacteria. A valid assessment of MYCO/F Lytic medium with regard to fungal isolation, however, was not possible due to the small number of isolates recovered.

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PCR-based Sepsis@Quick test is superior in comparison with blood culture for identification of sepsis-causative pathogens

Scientific Reports ◽

10.1038/s41598-019-50150-y ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Ngo Tat Trung ◽

Nguyen Sy Thau ◽

Mai Hong Bang ◽

Le Huu Song

Keyword(s):

Blood Culture ◽

Culture Conditions ◽

The Novel ◽

Human Dna ◽

Bacterial Genetic ◽

Polymerase Chain ◽

Blood Specimens ◽

First Time ◽

Positive Results ◽

Related Mortality

Abstract Sepsis is an acute, often fatal syndrome that requires early diagnosis and proper treatment. Blood culture (BC) is the gold standard for the identification of pathogens, however it has marked limitations, including that it is time-consuming (delaying treatment) and can only detect microbes that readily grow under culture conditions. Alternatively, non-culture-based methodologies like polymerase chain reaction (PCR) are faster but also have limitations; e.g., the reaction is often inhibited by the abundance of human DNA and thus can only detect limited known target pathogens. In our previous publication, we have demonstrated a proof-of-concept of a simple pre-analytical tool to remove human DNA from patients’ blood specimens, hence allowing downstream PCRs to detect rare bacterial genetic materials. In the current study, we reported a better performance of a novel prototype diagnosis kit named Sepsis@Quick that combines human DNA removal step with real-time PCRs compared to blood-culture for identifying sepsis causative bacteria. Our data showed that Sepsis@Quick is superior to blood culture in which the novel diagnostic kit could identify more pathogens and even polymicrobial infection, faster and less influenced by the empirical administration of broad spectrum antibiotic therapy (single administration or combination of cephalosporin III and fluoroquinolon). Additionally, for the first time, we demonstrated that positive results achieved by Sepsis@Quick are significantly associated with a reduction of sepsis-related mortality.

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