Blood stream infection (BSI),a blood-borne disease caused by microorganisms such as bacteria,fungi,and viruses,can lead to bacteremia,sepsis,and infectious shock,posing a serious threat to human life and health.Identifying the pathogen is central to the precise treatment of BSI.Traditional blood culture is the gold standard for pathogen identification,while it has limitations in clinical practice due to the long time consumption,production of false negative results,etc.Nanopore sequencing,as a new generation of sequencing technology,can rapidly detect pathogens,drug resistance genes,and virulence genes for the optimization of clinical treatment.This paper reviews the current status of nanopore sequencing technology in the diagnosis of BSI.
Humans ; Nanopore Sequencing ; Sepsis/diagnosis* ; Bacteremia/microbiology* ; Bacteria ; Blood Culture/methods*

INTRODUCTION: Differentiating infants with serious bacterial infections (SBIs) or invasive bacterial infections (IBIs) from those without remains a challenge. We sought to compare the diagnostic performances of single biomarkers (absolute neutrophil count [ANC], C-reactive protein [CRP] and procalcitonin [PCT]) and 4 diagnostic approaches comprising Lab-score, Step-by-Step approach (original and modified) and Pediatric Emergency Care Applied Research Network (PECARN) rule. METHOD: This is a prospective cohort study involving infants 0-90 days of age who presented to an emergency department from July 2020 to August 2021. SBIs were defined as bacterial meningitis, bacteraemia and/or urinary tract infections. IBIs were defined as bacteraemia and/or bacterial meningitis. We evaluated the performances of Lab-score, Step-by-Step (original and modified) and PECARN rule in predicting SBIs and IBIs. RESULTS: We analysed a total of 258 infants, among whom 86 (33.3%) had SBIs and 9 (3.5%) had IBIs. In predicting SBIs, ANC ≥4.09 had the highest sensitivity and negative predictive value (NPV), while PCT ≥1.7 had the highest specificity and positive predictive value (PPV). CRP ≥20 achieved the highest area under receiver operating characteristic curve (AUC) of 0.741 (95% confidence interval [CI] 0.672-0.810). The Step-by-Step (original) approach had the highest sensitivity (97.7%). Lab-score had the highest AUC of 0.695 (95% CI 0.621-0.768), compared to PECARN rule at 0.625 (95% CI 0.556-0.694) and Step-by-Step (original) at 0.573 (95% CI 0.502-0.644). In predicting IBIs, PCT ≥1.7 had the highest sensitivity, specificity, PPV and NPV. The Step-by-Step (original and modified) approach had the highest sensitivity of 100%. Lab-score had the highest AUC of 0.854 (95% CI 0.731-0.977) compared to PECARN rule at 0.589 (95% CI 0.420-0.758) and Step-by-Step at 0.562 (95% CI 0.392-0.732). CONCLUSION CRP strongly predicted SBIs, and PCT strongly predicted IBI. The Step-by-Step approach had the highest sensitivity and NPV, while Lab-score had the highest specificity and AUC in predicting SBIs and IBIs.
Infant ; Humans ; Child ; Calcitonin ; Prospective Studies ; Emergency Service, Hospital ; Bacterial Infections/diagnosis* ; Fever/diagnosis* ; C-Reactive Protein/analysis* ; Meningitis, Bacterial/diagnosis* ; Bacteremia ; Biomarkers ; Emergency Medical Services ; Procalcitonin

Pylephlebitis (septic thrombophlebitis of the portal venous system) is a rare but serious complication of intra-abdominal infections that drain into the portal venous system. Its diagnosis is based on imaging; computed tomography may reveal a thrombus in the portal vein. Bacteremia may also be evident. As the symptoms are nonspecific, early clinical diagnosis is difficult, and delayed treatment can compromise outcomes. We report a case with extensive pylephlebitis and a liver abscess associated with Streptococcus intermedius sepsis; the case was treated successfully with antibiotics and anticoagulants. Such cases have not been widely reported.
Anti-Bacterial Agents ; Anticoagulants ; Bacteremia ; Diagnosis ; Intraabdominal Infections ; Liver Abscess ; Liver ; Portal Vein ; Sepsis ; Streptococcus intermedius ; Streptococcus ; Thrombophlebitis ; Thrombosis

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.
Bacteremia ; Bacteria ; Bacteria, Anaerobic ; Candida ; Communicable Diseases ; Diagnosis ; Escherichia coli ; Fungi ; Gyeongsangnam-do* ; Imipenem ; Klebsiella pneumoniae ; Methods ; Pneumonia ; Pseudomonas aeruginosa ; Retrospective Studies ; Staphylococcus ; Staphylococcus aureus ; Streptococcus pneumoniae ; Vancomycin

BACKGROUND: We evaluated the performance of the BD MAX StaphSR Assay (SR assay; BD, USA) for direct detection of Staphylococcus aureus and methicillin resistance not only in S. aureus but also in coagulase-negative Staphylococci (CNS) from positive blood cultures. METHODS: From 228 blood culture bottles, 103 S. aureus [45 methicillin-resistant S. aureus (MRSA), 55 methicillin-susceptible S. aureus (MSSA), 3 mixed infections (1 MRSA+Enterococcus faecalis, 1 MSSA+MRCNS, 1 MSSA+MSCNS)], and 125 CNS (102 MRCNS, 23 MSCNS) were identified by Vitek 2. For further analysis, we obtained the cycle threshold (Ct) values from the BD MAX system software to determine an appropriate cutoff value. For discrepancy analysis, conventional mecA/mecC PCR and oxacillin minimum inhibitory concentrations (MICs) were determined. RESULTS: Compared to Vitek 2, the SR assay identified all 103 S. aureus isolates correctly but failed to detect methicillin resistance in three MRSA isolates. All 55 MSSA isolates were correctly identified by the SR assay. In the concordant cases, the highest Ct values for nuc, mecA, and mec right-extremity junction (MREJ) were 25.6, 22, and 22.2, respectively. Therefore, we selected Ct values from 0-27 as a range of positivity, and applying this cutoff, the sensitivity/specificity of the SR assay were 100%/100% for detecting S. aureus, and 97.9%/98.1% and 99.0%/95.8% for detecting methicillin resistance in S. aureus and CNS, respectively. CONCLUSIONS: We propose a Ct cutoff value for nuc/mec assay without considering MREJ because mixed cultures of MSSA and MRCNS were very rare (0.4%) in the positive blood cultures.
Anti-Bacterial Agents/pharmacology ; Bacteremia/diagnosis/microbiology ; Coagulase/metabolism ; Humans ; Methicillin-Resistant Staphylococcus aureus/drug effects/genetics/*isolation & purification ; Microbial Sensitivity Tests ; Oxacillin/pharmacology ; Reagent Kits, Diagnostic ; Staphylococcus/drug effects/enzymology/genetics/isolation & purification ; Staphylococcus aureus/drug effects/genetics/*isolation & purification

Group A streptococcus is a common cause of upper respiratory infection in children; however, it is a rare cause of pseudoaneurysm in pediatrics with only limited reports of cases associated with cardiac surgery and underlying disease. We report a case of infectious pseudoaneurysm of the right internal iliac artery caused by group A streptococcus in a previously healthy 5-year-old boy who presented with scarlet fever and group A streptococcal bacteremia. He was admitted to the hospital with fever, rash on the whole body, and sore throat, accompanied by severe leg pain. He was treated with surgical removal and antibiotics. Because a pseudoaneurysm may develop in children without vascularrelated underlying diseases, we should consider the possibility of this important clinical diagnosis in patients with scarlet fever.
Aneurysm, False* ; Aneurysm, Infected ; Anti-Bacterial Agents ; Bacteremia ; Child* ; Child, Preschool ; Diagnosis ; Exanthema ; Fever ; Humans ; Iliac Artery ; Leg ; Male ; Pediatrics ; Pharyngitis ; Scarlet Fever ; Streptococcus pyogenes ; Streptococcus* ; Thoracic Surgery

No abstract available.
Anti-Bacterial Agents/*pharmacology ; Bacteremia/*diagnosis/microbiology ; Colistin/*pharmacology ; Drug Resistance, Bacterial ; Escherichia coli/*drug effects/isolation & purification ; Humans ; Microbial Sensitivity Tests ; Republic of Korea

Group A streptococcus is a common cause of upper respiratory infection in children; however, it is a rare cause of pseudoaneurysm in pediatrics with only limited reports of cases associated with cardiac surgery and underlying disease. We report a case of infectious pseudoaneurysm of the right internal iliac artery caused by group A streptococcus in a previously healthy 5-year-old boy who presented with scarlet fever and group A streptococcal bacteremia. He was admitted to the hospital with fever, rash on the whole body, and sore throat, accompanied by severe leg pain. He was treated with surgical removal and antibiotics. Because a pseudoaneurysm may develop in children without vascularrelated underlying diseases, we should consider the possibility of this important clinical diagnosis in patients with scarlet fever.
Aneurysm, False* ; Aneurysm, Infected ; Anti-Bacterial Agents ; Bacteremia ; Child* ; Child, Preschool ; Diagnosis ; Exanthema ; Fever ; Humans ; Iliac Artery ; Leg ; Male ; Pediatrics ; Pharyngitis ; Scarlet Fever ; Streptococcus pyogenes ; Streptococcus* ; Thoracic Surgery

The incidence of bacteremia in human immunodeficiency virus (HIV)-infected patients is significantly decreased by highly active antiretroviral therapy (HAART). However, bacteremia remains a major cause of morbidity and mortality in HIV-infected patients. A 43-year-old male who had fever and cough for 1 week presented to the emergency room. He was diagnosed with acquired immunodeficiency syndrome combined with atypical pneumonia and started on antibiotics plus HAART. After 3 days, Streptococcus pneumoniae was grown in blood cultures. Three weeks later, acid-fast bacilli cultures of blood and bronchoalveolar lavage fluid grew Mycobacterium avium complex (MAC); hence, the patient was treated with antimycobacterial drugs. HIV-infected patients with persistent fever despite administration of appropriate antibiotics should be examined for simultaneous infection by other organisms, such as nontuberculous mycobacteria. We report a case of simultaneous detection of MAC and S. pneumoniae in the blood of a treatment-naïve HIV-infected patient.
Acquired Immunodeficiency Syndrome* ; Adult ; Anti-Bacterial Agents ; Antiretroviral Therapy, Highly Active ; Bacteremia ; Bronchoalveolar Lavage Fluid ; Cough ; Diagnosis* ; Emergency Service, Hospital ; Fever ; HIV ; Humans ; Incidence ; Male ; Mortality ; Mycobacterium avium Complex* ; Mycobacterium avium* ; Mycobacterium* ; Nontuberculous Mycobacteria ; Pneumonia ; Sepsis* ; Streptococcus pneumoniae

BACKGROUND: The objective of this study was to examine the usefulness of blood cultures and radiologic imaging studies for developing therapeutic strategies in community-acquired acute pyelonephritis (CA-APN) patients. MATERIALS AND METHODS: We prospectively collected the clinical data of CA-APN patients who visited 11 hospitals from March 2010 to February 2011. RESULTS: Positive urine and blood cultures were obtained in 69.3% (568/820) and 42.7% (277/648), respectively, of a total of 827 CA-APN patients. Blood culture identified the urinary pathogen in 60 of 645 (9.3%) patients for whom both urine and blood cultures were performed; the organisms isolated from urine were inconsistent with those from blood in 11 and only blood cultures were positive in 49 patients. Final clinical failure was more common in the bacteremic patients than the non-bacteremic ones (8.0% vs. 2.7%, P = 0.003), as was hospital mortality (3.6% vs. 0.3%, P = 0.003). Likewise, durations of hospitalization and fever were significantly longer. Bacteremia was independent risk factor for mortality (OR 9.290, 1.145-75.392, P = 0.037). With regard to radiologic studies, the detection rate of APN was 84.4% (445/527) by abdominal computed tomography and 40% (72/180) by abdominal ultrasonography. Eighty-one of 683 patients (11.9%) were found to have renal abscess, perinephric abscess, urolithiasis, hydronephorosis/hydroureter or emphysematous cystitis, which could potentially impact on clinical management. Patients with Pitt score ≥ 1, flank pain or azotemia were significantly more likely to have such structural abnormalities. CONCLUSION: Blood cultures are clinically useful for diagnosis of CA-APN, and bacteremia is predictive factor for hospital mortality. Early radiologic imaging studies should be considered for CA-APN patients with Pitt scores ≥1, flank pain or azotemia.
Abscess ; Azotemia ; Bacteremia ; Cystitis ; Diagnosis ; Diagnostic Imaging ; Fever ; Flank Pain ; Hospital Mortality ; Hospitalization ; Humans ; Mortality ; Prospective Studies ; Pyelonephritis* ; Risk Factors ; Ultrasonography ; Urolithiasis