Cardiac Magnetic Resonance Imaging for the Diagnosis of Infective Endocarditis in the COVID-19 Era

In the COVID-19 pandemic, to minimize aerosol-generating procedures, cardiac magnetic resonance imaging (CMR) was utilized at our institution as an alternative to transesophageal echocardiography (TEE) for diagnosing infective endocarditis (IE). This retrospective study evaluated the clinical utility of CMR for detecting IE among 14 patients growing typical microorganisms on blood cultures or meeting modified Duke Criteria. Seven cases were treated for IE. In 2 cases, CMR results were notable for possible leaflet vegetations and were clinically meaningful in guiding antibiotic therapy, obtaining further imaging, and/or pursuing surgical intervention. In 2 cases, vegetations were missed on CMR but detected on TEE. In 3 cases, CMR was non-diagnostic, but patients were treated empirically. There was no difference in antibiotic duration or outcomes over 1 year. CMR demonstrated mixed results in diagnosing valvular vegetations and guiding clinical decision-making. Further prospective controlled trials of CMR Vs TEE are warranted. © 2022 Elsevier Inc.

Giant liver abscess with Streptococcus intermedius bacteremia treated without any drainage.

A 66-year-old man with hypertension presented with fever which has started three days prior. Computed tomography (CT) revealed the presence of multiple low-density areas in the liver, the largest of which was over 10 cm in diameter, with clear demarcation. Streptococcus intermedius was detected in the blood culture, thus we diagnosed suspected liver abscess with bacteremia. Because the patient refused invasive drainage and was not poor general appearance, we had initiated intravenous meropenem followed by ceftriaxone plus metronidazole without any abscess drainage. After 6 weeks antibiotics treatment, liver abscess was almost completely diminished on the CT scan. To the best of our knowledge, this is the first report of a giant liver abscess caused by Streptococcus intermedius treated successfully without drainage.

Antimicrobial resistance prevalence of Escherichia coli and Staphylococcus aureus amongst bacteremic patients in Africa: a systematic review.

OBJECTIVES: Antimicrobial resistance (AMR) is a global concern among infectious diseases. Bloodstream infections can potentially become life-threatening if they become untreatable with conventional antimicrobials. This review aims to provide an understanding of the AMR prevalence and trends of common bacteremic pathogens, namely Escherichia coli and Staphylococcus aureus in the World Health Organization (WHO) Africa region. METHODS: PubMed and Google Scholar were searched using relevant keywords for published human studies (excluding case reports and reviews) reporting bacteremic AMR data on the pathogens of interest between 2008 and 2019. Two reviewers independently screened the articles against a pre-defined eligibility criterion. Data extraction and analysis were achieved with different platforms: Covidence, Excel, R version 3.6.3, and QGIS v3.4.5. The pooled prevalence, 95% confidence intervals, and I2 index (a measure of heterogeneity) were calculated for the various pathogen-antibiotic combinations. RESULTS: Five hundred sixty-two papers were retrieved, with 27 papers included in the final analysis. Only 23.4% (11/47) of member states of the WHO African region had reports on AMR in bacteremia. The Clinical and Laboratory Standards Institute (CLSI) (78.5%) was the most common standard used in the region. For E. coli, the pooled resistance was: cefotaxime (42%), imipenem (4%), meropenem (0%), and colistin (0%). For S. aureus, the calculated pooled resistance was cloxacillin (34%), oxacillin (12%), and vancomycin (0%). There was a high degree of variation across studies (I2 > 90%). CONCLUSION: The pooled resistance rates indicate a concerning degree of methicillin-resistant and Extended Spectrum-ß-lactamase-producing pathogens. The paucity of AMR data also presents challenges for a comprehensive understanding of the situation in the region. Continent-wide and standardized surveillance efforts therefore need strengthening.

Arcanobacterium haemolyticum bacteremia presenting as severe sepsis: A case report and review of the literature.

Objective: to describe a case of severe sepsis and complicated bacteremia caused by Arcanobacterium haemolyticum and review similar cases in the literature. Case summary: A 26-year-old gentleman with a history of epilepsy presented with symptoms of sore throat, productive cough, periumbilical abdominal pain, watery diarrhea, nausea and vomiting, subjective fevers along with progressive jaundice for seven days. The patient had acute fulminant liver failure, septic shock, and Multi-organ failure. He required vasopressors, underwent intubation, and had grown Arcanobacterium haemolyticum in the blood and Bronchoalveolar lavage samples. He developed a peritonsillar abscess and cavitary pneumonia and required chest tube drainage followed by thoracotomy for hemothorax. The patient improved on Ampicillin-Sulbactam treatment and was treated with a total antibiotic duration of 6 weeks. He fully improved on post-discharge follow-up. Discussion: Arcanobacterium haemolyticum is a Gram-positive (sometimes Gram variable), catalase-negative facultatively anaerobic, non-motile, non-spore-forming, and variably ß-hemolytic and is known to be a cause of pharyngitis and skin and soft tissue infections. Rarely A. Haemolyticum can be associated with severe systemic infections such as infective endocarditis, systemic abscesses, osteomyelitis, and septicemia. In previous literature reviews, the source of A. haemolyticum depended on the host, and pharyngeal and upper respiratory sources were likely to be associated with immunocompetent hosts. Conclusion: A. haemolyticum should be included in the differential diagnosis of bacterial pharyngitis complicated by severe systemic illness. Penicillins are the most commonly used antibiotics for treating A. haemolyticum bacteremia, and macrolides can be used for Penicillin's treatment failure.

Legionella pneumophila: The Journey from the Environment to the Blood.

An outbreak of a potentially fatal form of pneumonia in 1976 and in the annual convention of the American Legion was the first time that Legionella spp. was identified. Thereafter, the term Legionnaires' disease (LD) was established. The infection in humans is transmitted by the inhalation of aerosols that contain the microorganisms that belong to the Legionellaceae family and the genus Legionella. The genus Legionella contains genetically heterogeneous species and serogroups. The Legionella pneumophila serogroup 1 (Lp1) is the most often detected strain in outbreaks of LD. The pathogenesis of LD infection initiates with the attachment of the bacterial cells to the host cells, and subsequent intracellular replication. Following invasion, Legionella spp. activates its virulence mechanisms: generation of specific compartments of Legionella-containing vacuole (LCV), and expression of genes that encode a type IV secretion system (T4SS) for the translocation of proteins. The ability of L. pneumophila to transmigrate across the lung's epithelium barrier leads to bacteremia, spread, and invasion of many organs with subsequent manifestations, complications, and septic shock. The clinical manifestations of LD depend on the bacterial load in the aerosol, the virulence factors, and the immune status of the patient. The infection has two distinct forms: the non- pneumatic form or Pontiac fever, which is a milder febrile flu-like illness, and LD, a more severe form, which includes pneumonia. In addition, the extrapulmonary involvement of LD can include heart, brain, abdomen, and joints.

Multiple opportunistic infection in a male with systemic lupus erythematosus and concomitant human immunodeficiency virus infection

Background/Purpose: Concomitant systemic lupus erythematosus (SLE) and human immunodeficiency virus (HIV) infection cases are rare worldwide. It is established that SLE patients have an increased risk of opportunistic infection due to immune dysregulation, as well as in HIV. Method(s): A case of a 25-year- old Filipino man with systemic lupus erythematosus admitted due to a 1-week intermittent fever associated with headache, loss of appetite, and generalized body weakness was reviewed in a tertiary hospital in the Philippines. Result(s): An initial diagnosis was made from the clinical presentation of Raynaud's phenomenon, an elevated antinuclear antibody (1:320;nuclear, speckled), 2+ proteinuria, thrombocytopenia, and nail fold capillaroscopy findings consistent with mixed connective tissue disease. Patient was started on hydroxychloroquine and prednisone. He was admitted as a case of Streptococcus bacteremia with COVID-19 pneumonia after initial diagnosis, presenting as fever, and thrombocytopenia as low as 23.000/mul. Patient presented with a scaly erythematous annular lesion at his left wrist since December 2021 where a skin punch biopsy showed findings consistent with dermatophytosis. Direct immunofluorescence staining showed deposition of granular IgM (+3), C3 (+1), Fibrinogen (+3), and C1q (+1) in the basement membrane zone consistent with Lupus Erythematosus. Additional findings were oral thrush, dermatophytosis, and Pneumocystis pneumonia. Patient was started on antibiotics, remdesivir, and antifungal medications. Being severely immunocompromised, work up for HIV was initiated. Rapid HIV screening was positive, CD4 count revealed 7 (3.14%), and subsequent confirmatory western blot was positive. Additional treatment included hydroxychloroquine, methylprednisolone pulse therapy, and platelet concentrate transfusion. He was referred for CD4 monitoring, and ARV treatment enrollment, however, the patient expired a month after his discharge. Conclusion(s): This case is thereby reported to document a rare case of systemic lupus erythematosus (SLE) male patient with concomitant HIV, SARS-CoV- 2, and opportunistic infections secondary to AIDS. Diagnosis becomes challenging in patients with autoimmune diseases and multiple infectious diseases as clinical presentations tend to overlap and may show similar manifestations. In this setting, skin biopsy utilizing direct immunofluorescence can help establish an accurate diagnosis especially when clinical features and histopathology are overlapping.

Diagnostic significance of secondary bacteremia in patients with COVID-19.

OBJECTIVES: We investigated the occurrence of non-respiratory bacterial and fungal secondary infections, causative organisms, impact on clinical outcomes, and association between the secondary pathogens and mortality in hospitalized patients with coronavirus disease 2019 (COVID-19). METHODS: This was a retrospective cohort study that included data from inpatients with COVID-19 from multiple centers participating in the Japan COVID-19 Taskforce (April 2020 to May 2021). We obtained demographic, epidemiological, and microbiological data throughout the course of hospitalization and analyzed the cases of COVID-19 complicated by non-respiratory bacterial infections. RESULTS: Of the 1914 patients included, non-respiratory bacterial infections with COVID-19 were diagnosed in 81 patients (4.2%). Of these, 59 (3.1%) were secondary infections. Bacteremia was the most frequent bacterial infection, occurring in 33 cases (55.9%), followed by urinary tract infections in 16 cases (27.1%). Staphylococcus epidermidis was the most common causative organism of bacteremia. Patients with COVID-19 with non-respiratory secondary bacterial infections had significantly higher mortality, and a multivariate logistic regression analysis demonstrated that those with bacteremia (aOdds Ratio = 15.3 [5.97-39.1]) were at higher risk of death. Multivariate logistic regression analysis showed that age, male sex, use of steroids to treat COVID-19, and intensive care unit admission increased the risk for nosocomial bacteremia. CONCLUSIONS: Secondary bacteremia is an important complication that may lead to poor prognosis in cases with COVID-19. An appropriate medical management strategy must be established, especially for patients with concomitant predisposing factors.

Next-Generation Sequencing in Critically Ill COVID-19 Patients with Suspected Bloodstream Infections: A Retrospective Cohort Study.

BACKGROUND: Rapid pathogen identification and appropriate antimicrobial therapy are crucial in critically ill COVID-19 patients with bloodstream infections (BSIs). This study aimed to evaluate the diagnostic performance and potential therapeutic benefit of additional next-generation sequencing (NGS) of microbial DNA from plasma in these patients. METHODS: This monocentric descriptive retrospective study reviewed clinical data and pathogen diagnostics in COVID-19 ICU patients. NGS (DISQVER®) and blood culture (BC) samples were obtained on suspicion of BSIs. Data were reviewed regarding the adjustment of antimicrobial therapy and diagnostic procedures seven days after sampling and analyzed using the Chi²-test. RESULTS: Twenty-five cases with simultaneous NGS and BC sampling were assessed. The NGS positivity rate was 52% (13/25) with the detection of 23 pathogens (14 bacteria, 1 fungus, 8 viruses), and the BC positivity rate was 28% (7/25, 8 bacteria; p = 0.083). The NGS-positive patients were older (75 vs. 59.5 years; p = 0.03) with a higher prevalence of cardiovascular disease (77% vs. 33%; p = 0.03). These NGS results led to diagnostic procedures in four cases and to the commencement of four antimicrobial therapies in three cases. Empirical treatment was considered appropriate and continued in three cases. CONCLUSIONS: In COVID-19 patients with suspected BSIs, NGS may provide a higher positivity rate than BC and enable new therapeutic approaches.

Efficacy of Fosfomycin-Containing Regimens for Treatment of Bacteremia Due to Pan-Drug Resistant Acinetobacter baumannii in Critically Ill Patients: A Case Series Study.

Acinetobacter baumannii (AB) has evolved over the last decades as a major problem in carbapenem-resistant gram-negative nosocomial infections, associated with high mortality rates especially in the intensive care unit (ICU). Recent reports highlight the increasing prevalence of resistance to colistin, a last resort therapeutic option for carbapenem-resistant AB. We retrospectively evaluated the characteristics, treatment regimens and outcomes of twenty patients with pan-drug resistant (PDR) AB primary bacteremia hospitalized in the ICU of the University General Hospital of Patras, during a two-year period (October 2020-September 2022). The 28-day mortality reached 50%. Between survivors and non-survivors, no differences were found regarding age, gender, and Charlson comorbidity index (CCI). However, non-survivors had higher APACHE II scores and higher prevalence of septic shock and COVID-19 infection. A significantly higher percentage in the survivor group received Fosfomycin as part of the combination regimen. Inclusion of fosfomycin in the combination therapeutic regimen was associated with significantly better survival as compared to non-fosfomycin-containing regimens. In view of the increasing prevalence of PDR-AB infections in ICUs, its associated high rates of mortality and the lack of effective treatment options, the observed survival benefit with fosfomycin inclusion in the therapeutic regimen merits further validation in larger prospective studies.

Risk factors associated with bacteremia in COVID-19 patients admitted to intensive care unit: a retrospective multicenter cohort study.

PURPOSE: This multicenter observational study was done to evaluate risk factors related to the development of BSI in patients admitted to ICU for COVID-19. METHODS: All patients with COVID-19 admitted in two COVID-19 dedicated ICUs in two different hospital between 02-2020 and 02-2021 were recruited. RESULT: 537 patients were included of whom 265 (49.3%) experienced at least one BSI. Patients who developed bacteremia had a higher SOFA score [10 (8-12) vs 9 (7-10), p < 0.001], had been intubated more frequently [95.8% vs 75%, p < 0.001] and for a median longer time [16 days (9-25) vs 8 days (5-14), p < 0.001]. Patients with BSI had a median longer ICU stay [18 days (12-31.5) vs 9 days (5-15), p < 0.001] and higher mortality [54% vs 42.3%, p < 0.001] than those who did not develop it. Development of BSI resulted in a higher SOFA score [aHR 1.08 (95% CI 1.03-1.12)] and a higher Charlson score [csAHR 1.15 (95% CI 1.05-1.25)]. CONCLUSION: A high SOFA score and a high Charlson score resulted associated with BSI's development. Conversely, immunosuppressive therapy like steroids and tocilizumab, has no role in increasing the risk of bacteremia.