Persistent Positive Blood Cultures Research Articles

Clinicopathologic conference: Bloodstream infection in an allogeneic hamatopoietic cell transplant: Thinking beyond the usual.

This case involves a 53-year-old female with concurrent acute myeloid leukemia (AML) and multiple myeloma. She underwent cytarabine and daunorubicin (7+3) induction chemotherapy followed by cytarabine (HiDAC) consolidation, with an early AML relapse requiring azacitidine and venetoclax therapy. She achieved complete remission and incomplete count recovery. Following fludarabine, melphalan, and thymoglobulin induction chemotherapy, she underwent an allogeneic stem cell transplant with failure to engraft, requiring autologous stem cell rescue, buffy coat, and granulocyte transfusions, eventually presenting with a diffuse skin rash consistent with Steven-Johnson syndrome and toxic epidermal necrolysis, persistent neutropenic fevers and positive blood cultures.

Association of persistent positive blood cultures and infective endocarditis: A cohort study among patients with suspected infective endocarditis

ObjectivesTo ascertain whether infective endocarditis (IE) was associated with persistent bacteraemia/candidaemia among patients with suspected IE. MethodsThis study included bacteraemic/candidaemic adult patients with echocardiography and follow-up blood cultures. Persistent bacteraemia/candidaemia was defined as continued positive blood cultures with the same microorganism for 48 h or more after antibiotic treatment initiation. Each case was classified for IE by the Endocarditis Team. ResultsAmong 1962 episodes of suspected IE, IE (605; 31%) was the most prevalent infection type. Persistent bacteraemia/candidaemia was observed in 426 (22%) episodes. Persistent bacteraemia was more common among episodes with Staphylococcus aureus bacteraemia compared to episodes with positive blood cultures for other pathogens (32%, 298/933 vs 12%, 128/1029; P < 0.001). Multivariable analysis demonstrated that cardiac predisposing factors (aOR 1.84, 95% CI 1.31-2.60), community or non-nosocomial healthcare-associated (2.85, 2.10-3.88), bacteraemia by high-risk bacteria, such as S. aureus, streptococci, enterococci or HACEK (1.84, 1.31-2.60), two or more positive sets of index blood cultures (6.99, 4.60-10.63), persistent bacteraemia/candidaemia for 48 h from antimicrobial treatment initiation (1.43, 1.05-1.93), embolic events within 48h from antimicrobial treatment initiation (12.81, 9.43-17.41), and immunological phenomena (3.87, 1.09-1.78) were associated with infective endocarditis. ConclusionsIE was associated with persistent bacteraemia/candidaemia, along with other commonly associated factors.

Bacteria in Extracorporeal Membrane Oxygenation Circuit Clots of a Patient With Persistent Bacteremia: A Case Report.

A neonate with pulmonary hypertension was supported with extracorporeal membrane oxygenation (ECMO). During ECMO support, the patient developed Enterococcus faecalis bacteremia, treated with targeted antibiotics. Despite the maximum dose of antibiotics, routine blood cultures remained positive throughout the ECMO treatment. A circuit change was performed due to buildup of thrombotic material and disseminated intravascular coagulation (DIC) inside the circuit. Thrombus formation was more extensive in the first than the second circuit. Gram-positive diplococci were present in all initial circuit clots and gram-positive masses surrounded by fibrin were found inside thrombi of the second circuit. Scanning electron microscopy (SEM) revealed a dense fibrin network with embedded red blood cells and bacteria in the first circuit. In the second circuit, SEM analysis revealed scattered micro thrombi. Polymerase chain reaction for identification of bacteria in the thrombus of the first circuit showed the same bacteria as found in blood cultures and did not achieve a sufficient signal in the second circuit. This case report shows that bacteria can nestle in thrombi of an ECMO circuit and that there is a rationale for a circuit change in a patient with persistent positive blood cultures and DIC.

Metastatic infections in pediatric patients with Staphylococcus aureus bacteremia assisted at a children's hospital in La Plata, Argentina.

Staphylococcus aureus is one of the most prevalent infectious agents in children and may cause a wide variety of clinical presentations. S. aureus bacteremia is frequently associated with complications and metastatic infections. The epidemiological and clinical data about S. aureus bacteremia and its complications in pediatrics are scarce. To describe the epidemiology, frequency, distribution, and type of metastatic infections in a series of pediatric patients with S. aureus bacteremia and assess possible risk factors for its development. Cross-sectional study of pediatric patients with S. aureus bacteremia admitted to a children's hospital of La Plata between January 2016 and June 2019. A total of 112 S. aureus bacteremia events were analyzed. The rate of metastatic infection was 34.8%; the lung was the most common infection site. The main risk factors for the development of metastatic infections were bacteremia due to methicillin-resistant S. aureus (odds ratio: 2.95; 95% confidence interval: 1.19- 7.83; p = 0.015) and persistent positive control blood cultures at 48 hours (odds ratio: 3.17; 95% confidence interval: 1.22-8.46; p = 0.012). The rate of metastatic infections among patients with S. aureus bacteremia was 34.8%. Associated risk factors were bacteremia due to methicillin-resistant S. aureus and persistent positive control blood cultures at 48 hours. The most common organs affected included the lungs, the osteoarticular system, and the skin and soft tissue.

Outcomes of Standard Permanent Active Fixation Leads for Temporary Pacing.

This study investigated the performance of Temporary Pacing via an Externalized Active-Fixation (TPEAF) lead. The incidence of cardiac implantable electronic device infections is increasing, which necessitates the need for transvenous lead extraction (TLE). Pacemaker-dependent patients require temporary pacing during the guideline-recommended waiting period before reimplantation. Data regarding safety and efficacy of TPEAF leads are very limited. We evaluated patients implanted with TPEAF leads post-TLE at our center between April 2004 and December2017. TPEAF leads were placed in 158 patients. The mean age was 74 ± 11 years. The median duration of the temporary lead was 6days (range 1 to 29). There were 4 procedural complications (2.5% incidence): 1 patient had cardiac arrest from hyperkalemia, 2 developed cardiac tamponade, and 1 had profuse bleeding from the entry point of the leads. There were 13 complications post-implantation (8.2% incidence): 8 lead dislodgments, 1 elevated pacing threshold, 2 vegetations on the temporary lead, 1 pneumothorax, and 1 loss of capture due to the generator "safety switch." All dislodgements occurred within 24 h, except 1 on day 3. Sixteen patients died during the hospital stay: 10 due to septic shock, 2 due to hyperkalemic cardiac arrest, 3 due to ventricular tachycardia, and 1 due to a massive cerebrovascular accident. The use of TPEAF leads is safe and efficacious in pacemaker-dependent patients post-TLE. Dislodgement can occur within the first 24 h. The presence of persistent fever and positive blood cultures should raise concern for vegetation on the temporary lead.

2171. Phenotypic Correlations for the Presence of CTX-M in Enterobacteriaceae and mecA in Staphylococcus aureus using the Verigene® Blood Culture System

BackgroundRapid identification of antimicrobial resistance markers has the potential to help targeting antimicrobial therapy and enhance efforts for antibiotic stewardship. However, limited data are available to correlate phenotypic and genotypic results for some of these platforms in positive blood cultures (BC). Here, we aimed to evaluate the ability of the Verigene® (VG) Blood Culture System to predict phenotypic susceptibility patterns with the detection of the genes encoding the CTX-M in Enterobacteriaceae and MecA in S. aureus (SA) in a large dataset.MethodsPhenotypic susceptibility and VG results were retrospectively collected between August 2017 and December 2018 from 12 hospitals in Houston, TX. VG testing was performed on only the first isolate was considered in persistent positive BCs. The VG report of the presence of blaCTX-M or mecA was correlated with phenotypic susceptibility to ceftriaxone (CTO) (E. coli [EC] and Klebsiella spp.[KL]) or oxacillin (SA), respectively.ResultsWe identified a total of 5,937 VG results. The final analysis was performed on 2,356 cases where EC, KL or SA was identified. Isolates detected KPC and NDM by VG were excluded. 30 EC/KL were missed by VG in polymicrobial bacteremia. 7 polymicrobial positive BCs with coagulase-negative staphyloccocci were mislabeled as MecA positive MSSA. Among isolated detected by VG, there were the high sensitivity and specificity of CTX-M to identify CTO resistance (97.2% and 99.7% in EC and 91.4% and 99.2% in KL). For SA, the sensitivity and specificity of mecA were 100% and 99.6% to identify oxacillin resistance. 2 isolates with mecA positive by VG were reported as oxacillin-suscpetible.ConclusionOur results revealed that there is a high correlation between VG and phenotype. For SA, discrepancies between genotype and phenotype seem to be influenced by the presence of other organisms in the sample. Genotypic information seems reliable and should guide targeted therapy in bloodstream infections. Disclosures All authors: No reported disclosures.

Streptococcus gallolyticus-induced 'kissing abscess' of anterior mitral valve leaflet and intervalvular fibrosa from an aortic valve endocarditis – a case of delayed diagnosis

A fatal disease until Mid-Twentieth Century, nowadays infective endocarditis is curable due to advances in diagnostic techniques, especially in echocardiography, the possibility of cardiac surgery during the active infectious process and new antibiotics. We present a 62 years-old man, with no significant past medical illness, referred for persistent cough, fatigue, shortness of breath, loss of weight and paleness, with recent history of persistent fever and positive blood cultures with Streptococcus gallolyticus. Echocardiographic examination revealed aortic and mitral valve vegetations and anterior mitral valve leaflet abscess. During surgery, the presence of a “kissing abscess” on the atrial side of the anterior mitral leaflet, arising from a vegetation on the non-coronary cusp of the aortic valve, was confirmed, together with an intervalvular fibrosa abscess. Special reinforcement with an oversewn bovine pericardial patch and reconstruction of the intervalvular fibrous body was necessary during aortic and mitral valve replacement. Despite delayed diagnosis, the case had a favorable outcome, the patient being discharged presenting a good clinical state. Numerous complications, including abscesses and early infective endocarditis on prosthetic aortic valve, would have been probably avoided with prompt recognition and early treatment of endocarditis.

Early Response Assessment to Guide Management of Methicillin-Resistant Staphylococcus aureus Bloodstream Infections With Vancomycin Therapy

BackgroundA subset of vancomycin-treated patients with methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection (BSI) developed persistent positive blood cultures. Treatment eventually failed. MethodsA retrospective study was conducted to determine whether early response on day 3 after initiation of vancomycin therapy for MRSA BSI was associated with reduced rates of persistent bacteremia, end-of-treatment failure, and infection-related mortality. Patients’ medical charts were reviewed. Susceptibility testing and molecular characterization of bacterial isolates were performed. ResultsIn this elderly cohort (n = 111; median age 70 years, interquartile range: 57–80 years), early response was observed in 62% of patients and was significantly (P < 0.0001) associated with lower rates of end-of-treatment failure (19% vs 57%) and infection-related death (1% vs 29%), but not with persistent bacteremia (17% vs 29%, P = 0.23). Nearly half (46%; 46 of 100 patients) remained on vancomycin therapy for the entire treatment course; those who continued despite lack of early response had a trend toward a higher risk of death than those who were switched to alternative therapy (38% vs 10%, P = NS). Most (68%) isolates had vancomycin MIC of >1 µg/mL, whereas 10% showed heterogeneous glycopeptide-intermediate Staph aureus (hGISA) phenotype. Nearly half (47%) were typed with staphylococcal cassette chromosome mec IV or V. In a multivariate logistic regression model, lack of response at day 3 was the strongest predictor for end-of-treatment failure, after adjustment for confounders such as age, Acute Physiology And Chronic Health Evaluation II score, intensive care unit admission, vancomycin MIC >1 µg/mL, unbound trough concentration <4 to 5× MIC, and continued vancomycin therapy without change. ConclusionsEarly response assessment after initiation of vancomycin therapy appeared to be useful for considering further diagnostic workup or a switch to alternative therapy to affect a positive outcome in patients with MRSA BSI.

Prognostic role of persistent positive blood cultures after initiation of antibiotic therapy in left-sided infective endocarditis

Persistent infection is not a scientific evidence-based definition. The guidelines of infective endocarditis (IE) establish a cut-off point of 7-10 days, which is arbitrary and probably too long. Our hypothesis is that persistent positive blood cultures after 48-72 h from the initiation of antibiotic therapy are associated with a worse prognosis in patients with left-sided IE. We repeated blood cultures after 48-72 h of the initiation of the antibiotic treatment in 407 patients with left-sided IE of a total of 692 episodes consecutively diagnosed from 1996 to 2011. We have compared the profile of patients whose blood cultures became negative and those with persistent positive blood cultures. We performed a multivariate logistic regression model to determine the prognostic implication of persistent positive blood cultures. Of 256 patients with positive blood cultures at admission, 89 (35%) had persistent positive cultures after 48-72 h from the initiation of the antibiotic treatment. Persistent positive blood cultures (OR: 2.1; 95% CI: 1.2-3.6), age (OR: 1.026; 95% CI: 1.007-1.046), Staphylococcus aureus infection (OR: 3.3; 95% CI: 1.6-6.6), heart failure (OR: 2.8; 95% CI: 1.6-4.7), and renal failure (OR: 2.9; 95% CI: 1.8-4.9) were found to be independently associated with higher in-hospital mortality. The presence of persistent positive blood cultures is an independent risk factor for in-hospital mortality which doubles the risk of death of patients with left-sided IE. It should be taken into account in the risk stratification of these patients.

Endophthalmitis as a first manifestation of right-sided endocarditis in a patient with patent foramen ovale.

Endogenous endophthalmitis is a rare complication of endocarditis, rendering poor visual prognosis. We report a case of a 66-year-old female with renal failure who presented with fever, ocular pain, and purulent eye discharge. After a diagnosis of endogenous endophthalmitis, she was treated with antibiotics and enucleation of the eye. Due to persistent fever and positive blood cultures, a transesophageal echocardiography was undertaken, disclosing a large mural vegetation in the right atrium, catheter-associated vegetations, and a patent foramen ovale. Endocarditis is an uncommon source of endogenous endophthalmitis, and has rarely been associated to right-sided endocarditis and paradoxical septic embolization.

Persistent coagulase-negative staphylococci bacteremia in very-low-birth-weight infants

This study sought to expand current knowledge on the clinical and epidemiological characteristics of persistent coagulase-negative Staphylococcus (CoNS) bacteremia in very-low-birth-weight (VLBW) infants. Background and disease-related data were collected prospectively on 143 VLBW infants diagnosed with CoNS bacteremia at a pediatric tertiary medical center in 1995-2003. Findings were compared between those with persistent (positive blood cultures for >72h under appropriate treatment ) and nonpersistent disease. Fifty-eight infants (40.6%) were found to have persistent bacteremia. There were no between-group differences in maternal characteristics, mode of delivery, newborn characteristics, dwell time of central venous and umbilical catheters, complications of prematurity, or mean hospital stay. The persistent bacteremia group had significantly higher rates of hypothermia at presentation (37.9% vs. 17.6%, p < 0.04), creatinine >1.2mg% on treatment day7 (13.7% vs. 2.4%, p < 0.02; transient phenomenon), and endocarditis (p < 0.03); one infant had an aortic thrombus. Predominantly breast-fed infants had a higher rate of negative cultures within 72h of appropriate treatment than predominantly formula-fed infants (60% vs. 19%, p < 0.02). In conclusion, persistence of CoNS bacteremia is common in VLBW infants. Endocarditis should be excluded in all infants with persistent disease. Breast-feeding is associated with a shorter disease duration.

Abdominal Catastrophe in a 43‐Year‐Old Female with End Stage Renal Disease

A 43-year-old female with end-stage renal disease secondary to focal segmental glomerulosclerosis was admitted to the hospital for shortness of breath after missing hemodialysis. On admission, the patient was noted to have painful skin lesions consistent with calciphylaxis on biopsy. While undergoing aggressive wound care, she developed altered mental status and was found to be septic and started empirically on broad-spectrum antibiotics. The patient was intubated on day 4 of admission owing to worsening mental status and acidemia. She had persistent positive blood cultures throughout her hospitalization despite appropriate antibiotic therapy. On day 25 of admission, the patient was found to have abdominal distension. A radiograph revealed intra-abdominal free air, and the patient was taken to the operating room where she was found to have perforated necrotic bowel. The patient expired on day 26 of admission. An autopsy revealed calciphylaxis within the gut wall and within the dura of the central nervous system. While typically a disorder of subcutaneous tissue, calciphylaxis can affect internal organs, which in this case resulted in a catastrophic outcome.

Targeted Neonatal Echocardiography (TnECHO) and Increased Detection of Intracardiac Thrombi and Endocarditis in Very low Birth Weight Infants

Objectives: Infective Endocarditis is a rare but potentially serious condition in very low birth weight infants and we aimed to evaluate the incidence and outcomes in this population. Study design: 203 infants <1500g were admitted to the NICU over 24 months. Routine echocardiography was introduced in the unit on all infants <1500g by a neonatologist trained in echocardiography. Echocardiography was specifically requested for persistent positive blood cultures, new onset murmur and patent ductus arteriosus evaluation. Results: Five infants were diagnosed with endocarditis giving an incidence of 2.5% compared to 0.4% in the previous 2 years. There were no cases of Congenital Heart Disease. All infants had a history of central venous or central arterial catheter use and received six weeks of antibiotic treatment. Four infants with endocarditis had persistently positive blood cultures and 2 infants received low molecular weight heparin. In all but one case, the sepsis resolved and the vegetative intracardiac lesions disappeared prior to completion of treatment.Conclusion: The diagnosis of endocarditis increased in VLBWs which coincided with institution of regular echocardiography. Thrombocytopenia, persistent positive blood cultures and a new murmur require urgent echocardiography to outrule endocarditis in VLBW infants.

Candida infective endocarditis

Candida infective endocarditis (IE) is uncommon but often fatal. Most epidemiologic data are derived from small case series or case reports. This study was conducted to explore the epidemiology, treatment patterns, and outcomes of patients with Candida IE. We compared 33 Candida IE cases to 2,716 patients with non-fungal IE in the International Collaboration on Endocarditis-Prospective Cohort Study (ICE-PCS). Patients were enrolled and the data collected from June 2000 until August 2005. We noted that patients with Candida IE were more likely to have prosthetic valves (p < 0.001), short-term indwelling catheters (p < 0.0001), and have healthcare-associated infections (p < 0.001). The reasons for surgery differed between the two groups: myocardial abscess (46.7% vs. 22.2%, p = 0.026) and persistent positive blood cultures (33.3% vs. 9.9%, p = 0.003) were more common among those with Candida IE. Mortality at discharge was higher in patients with Candida IE (30.3%) when compared to non-fungal cases (17%, p = 0.046). Among Candida patients, mortality was similar in patients who received combination surgical and antifungal therapy versus antifungal therapy alone (33.3% vs. 27.8%, p = 0.26). New antifungal drugs, particularly echinocandins, were used frequently. These multi-center data suggest distinct epidemiologic features of Candida IE when compared to non-fungal cases. Indications for surgical intervention are different and mortality is increased. Newer antifungal treatment options are increasingly used. Large, multi-center studies are needed to help better define Candida IE.

Positive surveillance blood culture is a predictive factor for secondary metastatic infection in patients with Staphylococcus aureus bacteraemia.

Staphylococcus aureus bacteraemia (SAB) may be complicated by secondary metastatic infection such as endocarditis, osteomyelitis or septic arthritis. This cohort study aimed to assess the prognostic value of sustained bacteraemia for outcomes related to Staphylococcus aureus bacteraemia. The study took place in three tertiary-care, university-affiliated hospitals. Patients were prospectively included if they agreed to participate and if the following data were available: (a). surveillance blood culture taken between 24 and 48 h after commencement of effective antibiotic therapy; (b). appropriate investigations (at least a TTE) performed as suggested by the infectious diseases consult service. Patients with sustained bacteraemia defined as persistent positive blood cultures more than 24 h after commencement of effective antibiotic therapy were compared to patients for whom the surveillance blood culture was negative. One hundred and four patients were enrolled, including 51 patients diagnosed with sustained bacteraemia. Sustained bacteraemia was significantly associated with a higher frequency of secondary metastatic infection (p<0.001) and with a higher frequency of CRP>100 mg/l. Frequency of acute complications due to infection, septic shock and death due to bacteraemia was higher for patients with sustained bacteraemia but this difference was not statistically significant. Using a Cox model, the risk for death associated with sustained SAB, controlling for Index of comorbidity and age (categorised as<or>or=70 years), was 1.2 (95% CI: (0.5, 3); p>0.05). In conclusion, surveillance blood cultures, especially performed on effective antibiotic therapy, may be a simple and cost-effective way to select a population at risk for secondary metastatic infection from SAB.

Acute bacterial endocarditis following burns: case report and review

Acute bacterial endocarditis (ABE) is a rare but deadly complication following major thermal injury. Typically the presentation is silent, with persistent fever and positive blood cultures being the only consistent findings. Fibrin-platlet vegetations on the valvular endocardium are thought to be seeded during bacteremic episodes. Manipulation of the burn wound is probably the most likely source of bacteremia, with Staphylococcus aureus and Gram-negative bacilli being the most commonly implicated bacteria. In addition to causing local damage to a valve or the myocardium, infected vegetations may dislodge septic emboli systemically. Diagnosis is most easily obtained by echocardiography. Treatment usually involves prolonged administration of intravenous antibiotics. In rare circumstances, valvular resection and replacement may be indicated.

Central Venous Line Thrombosis in Premature Infants: A Case Management and Literature Review

Increased risk of central venous line thrombosis in tiny premature infants occurs because the size of the catheter relative to the cross-sectional area of the vessel is large, decreased plasma levels of plasminogen and antithrombin III, and relative low flow of the infusate through the catheter, in comparison with larger infants. A potentially fatal complication of central venous catheters is an intracardiac thrombus. The yield of detecting right atrial thrombi by routine echocardiographic monitoring is very low. Persistent positive blood cultures in infants with central venous lines, in spite of appropriate antibiotic therapy, or signs of catheter occlusion, may increase the yield of echocardiographic detection of intracardiac thrombi. Surgical removal of intracardiac thrombi in infants weighing less than 1500 gm carries a high mortality rate because of the need to use cardiopulmonary bypass with total circulatory arrest and profound hypothermia during surgery. It is in these infants that thrombolysis with urokinase should be considered. A successful therapy with urokinase of a complete occlusion of the right pulmonary artery by an embolus originating from the right atrium is described in a premature infant. For thrombolysis, a loading dose of urokinase of 4400 U/kg followed by 4400 to 8800 U/kg/hr for a few days was used. The thrombolytic effect was manifested by decreased thrombus echogenicity followed by its disappearance, by increased fibrinogen split products, and by decreased plasma fibrinogen. Urokinase therapy may cause massive bleeding, dislodge an intracardiac thrombus causing obstruction of cardiac valves or main vessels or causing embolization to the pulmonary or systemic circulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Persistent Bacteremia Due to Coagulase-Negative Staphylococci in Low Birth Weight Neonates

During a 6-month period in 1987, 13 low birth weight neonates without indwelling central intravascular catheters had persistent (positive blood cultures for greater than or equal to 6 days) coagulase-negative staphylococcal bacteremia despite adequate antibiotic therapy. Daily blood cultures remained persistently positive for a mean of 13 days (range 6 to 25 days). This group of infants was compared with other low birth weight infants with similar birth weights and nonpersistent coagulase-negative staphylococcal bacteremia, defined as two or more positive blood cultures accompanied by supporting clinical manifestations of sepsis. During this period, coagulase-negative staphylococcal represented 29% of all bacteremias, and 33% of coagulase-negative staphylococcal bacteremias were persistent. Other than soft tissue abscesses, none of the infants with persistent coagulase-negative staphylococcal bacteremia had a defined focus of infection. Abdominal distention (P = .001) and thrombocytopenia (P less than .03) occurred significantly more frequently in the patients with persistent coagulase-negative staphylococcal bacteremia than in those with nonpersistent bacteremia. Of the 13 patients with persistent coagulase-negative staphylococcal bacteremia, 2 received methicillin and 11 received vancomycin. No antibiotic tolerance to either antibiotic could be demonstrated. Serum concentrations of vancomycin far exceeded the minimum bactericidal concentration in all cases in which vancomycin was prescribed. No in vitro differences could be demonstrated between persistent and nonpersistent coagulase-negative staphylococcal strains for slime production, biotype, proteins from modified whole cell lysates developed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and opsonophagocytosis by adult neutrophils in the presence of pooled human sera. Additionally, plasmid profile analysis and phage typing revealed no common strain causing the persistent bacteremia.(ABSTRACT TRUNCATED AT 250 WORDS)