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1.
Nat Commun ; 12(1): 4117, 2021 07 05.
Article in English | MEDLINE | ID: mdl-34226537

ABSTRACT

Epidemiological and clinical reports indicate that SARS-CoV-2 virulence hinges upon the triggering of an aberrant host immune response, more so than on direct virus-induced cellular damage. To elucidate the immunopathology underlying COVID-19 severity, we perform cytokine and multiplex immune profiling in COVID-19 patients. We show that hypercytokinemia in COVID-19 differs from the interferon-gamma-driven cytokine storm in macrophage activation syndrome, and is more pronounced in critical versus mild-moderate COVID-19. Systems modelling of cytokine levels paired with deep-immune profiling shows that classical monocytes drive this hyper-inflammatory phenotype and that a reduction in T-lymphocytes correlates with disease severity, with CD8+ cells being disproportionately affected. Antigen presenting machinery expression is also reduced in critical disease. Furthermore, we report that neutrophils contribute to disease severity and local tissue damage by amplification of hypercytokinemia and the formation of neutrophil extracellular traps. Together our findings suggest a myeloid-driven immunopathology, in which hyperactivated neutrophils and an ineffective adaptive immune system act as mediators of COVID-19 disease severity.


Subject(s)
COVID-19/complications , COVID-19/immunology , Cytokine Release Syndrome/complications , Monocytes/pathology , Neutrophil Activation , Aged , Antigen-Presenting Cells/immunology , COVID-19/blood , COVID-19/virology , Case-Control Studies , Cytokine Release Syndrome/blood , Cytokine Release Syndrome/pathology , Cytokine Release Syndrome/virology , Cytokines/blood , Extracellular Traps/metabolism , Female , Histocompatibility Antigens Class II/metabolism , Humans , Immunophenotyping , Male , Middle Aged , SARS-CoV-2/physiology , Severity of Illness Index
2.
Virulence ; 12(1): 570-583, 2021 12.
Article in English | MEDLINE | ID: mdl-33525982

ABSTRACT

Pattern recognition receptors (PRRs) are responsible for Aspergillus fumigatus recognition by innate immunity and its subsequent immune signaling. The triggering receptor expressed on myeloid cells 1 (TREM1) is a recently characterized pro-inflammatory receptor constitutively expressed on the surface of neutrophils and macrophages. A soluble form (sTREM1) of this protein that can be detected in human body fluids has been identified. Here we investigated the role of TREM1 during invasive pulmonary aspergillosis (IPA). IPA patients displayed significantly higher levels of sTREM1 in bronchoalveolar lavages when compared to control patients. Functional analysis in TREM1 showed that the levels of sTREM1 and TREM1 pathway-related cytokines were influenced by single nucleotide polymorphisms in TREM1. In addition, we confirmed a role of TREM1 on antifungal host defense against A. fumigatus in a murine model of IPA. TREM1 deficiency increased susceptibility to infection in the immunosuppressed murine host. Deletion of TREM1 showed delayed innate and adaptive immune responses and impaired pro-inflammatory cytokine responses. The absence of TREM1 in primary macrophages attenuated the TLR signaling by altering the expression of both receptor and effector proteins that are critical to the response against A. fumigatus. In this study, and for the first time, we demonstrate the key role for the TREM1 receptor pathway during IPA.


Subject(s)
Aspergillus fumigatus/immunology , Gene Expression Regulation/immunology , Immunity, Innate , Triggering Receptor Expressed on Myeloid Cells-1/genetics , Adult , Animals , Bronchoalveolar Lavage Fluid/chemistry , Cytokines , Disease Models, Animal , Female , Humans , Immunocompromised Host , Invasive Pulmonary Aspergillosis , Lung/microbiology , Male , Mice , Middle Aged , Triggering Receptor Expressed on Myeloid Cells-1/immunology
3.
IDCases ; 22: e00971, 2020.
Article in English | MEDLINE | ID: mdl-33088713

ABSTRACT

Disseminated histoplasmosis is a rare opportunistic infection in non-endemic areas, where the disease is often diagnosed late. The spectrum of clinical manifestations is broad and life-threatening complications occur. We present a detailed case of a kidney liver transplant patient with disseminated histoplasmosis in a non-endemic area. Our case highlights the wide range of pathogens to consider in the immunocompromised patient, the delayed diagnosis of Histoplasmosis Capsulatum in non-endemic areas and the possibility of severe gastrointestinal disease. We also briefly review diagnostic tests and treatment options.

4.
Acta Neurol Belg ; 120(5): 1033-1043, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32666505

ABSTRACT

Acute bacterial meningitis (ABM) is a rare but disabling infectious condition that requires a performant multidisciplinary management approach. Between 70 and 90 adult patients are diagnosed with community-acquired ABM in Belgium annually, and reported case fatality rates range from 17 to 40%. The currently available guidelines provide evidence-based guidance on how to manage this disease. However, these guidelines do not translate the evidence to the daily practice at the emergency department in a Belgian healthcare context. We created a taskforce in University Hospitals Leuven consisting of experts with complementary expertise in managing this disease: neurology, neurosurgery, intensive care medicine, microbiology and infectious diseases. The taskforce agreed upon a flowchart containing seven management steps encompassing all relevant phases in emergency ABM management. In addition to the focus on timely and adequate initiation of antimicrobial treatment, the flowchart and protocol also provide guidance on practical hurdles such as how to assess the safety of performing a lumbar puncture and when to refer patients to the intensive care department. This protocol was implemented in University Hospitals Leuven and fosters inter-disciplinary coordination of ABM care.


Subject(s)
Community-Acquired Infections/diagnosis , Community-Acquired Infections/therapy , Emergency Medical Services/standards , Meningitis, Bacterial/diagnosis , Meningitis, Bacterial/therapy , Adult , Belgium , Emergency Medical Services/methods , Emergency Service, Hospital/standards , Female , Humans , Male
5.
Clin Microbiol Infect ; 26(8): 1082-1087, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32473953

ABSTRACT

OBJECTIVES: To evaluate the diagnostic performance of seven rapid IgG/IgM tests and the Euroimmun IgA/IgG ELISA for antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in COVID-19 patients. METHODS: Specificity was evaluated in 103 samples collected before January 2020. Sensitivity and time to seropositivity was evaluated in 167 samples from 94 patients with COVID-19 confirmed with RT-PCR on nasopharyngeal swab. RESULTS: Specificity (confidence interval) of lateral flow assays (LFAs) was ≥91.3% (84.0-95.5) for IgM, ≥90.3% (82.9-94.8) for IgG, and ≥85.4% (77.2-91.1) for the combination IgM OR IgG. Specificity of the ELISA was 96.1% (90.1-98.8) for IgG and only 73.8% (64.5-81.4) for IgA. Sensitivity 14-25 days after the onset of symptoms was between ≥92.1% (78.5-98.0) and 100% (95.7-100) for IgG LFA compared to 89.5% (75.3-96.4) for IgG ELISA. Positivity of IgM OR IgG for LFA resulted in a decrease in specificity compared to IgG alone without a gain in diagnostic performance, except for VivaDiag. The results for IgM varied significantly between the LFAs with an average overall agreement of only 70% compared to 89% for IgG. The average dynamic trend to seropositivity for IgM was not shorter than for IgG. At the time of hospital admission the sensitivity of LFA was <60%. CONCLUSIONS: Sensitivity for the detection of IgG antibodies 14-25 days after the onset of symptoms was ≥92.1% for all seven LFAs compared to 89.5% for the IgG ELISA. The results for IgM varied significantly, and including IgM antibodies in addition to IgG for the interpretation of LFAs did not improve the diagnostic performance.


Subject(s)
Antibodies, Viral/analysis , Antigens, Viral/immunology , Betacoronavirus/immunology , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , Adult , Aged , Aged, 80 and over , COVID-19 , Coronavirus Infections/immunology , Diagnostic Tests, Routine , Female , Humans , Immunoglobulin A/metabolism , Immunoglobulin G/metabolism , Immunoglobulin M/metabolism , Male , Middle Aged , Pandemics , Pneumonia, Viral/immunology , SARS-CoV-2 , Sensitivity and Specificity , Time Factors , Young Adult
7.
Infect Immun ; 88(4)2020 03 23.
Article in English | MEDLINE | ID: mdl-31964743

ABSTRACT

Invasive aspergillosis (IA) is a life-threatening infection that affects an increasing number of patients undergoing chemotherapy or allo-transplantation, and recent studies have shown that genetic factors contribute to disease susceptibility. In this two-stage, population-based, case-control study, we evaluated whether 7 potentially functional single nucleotide polymorphisms (SNPs) within the ARNT2 and CX3CR1 genes influence the risk of IA in high-risk hematological patients. We genotyped selected SNPs in a cohort of 500 hematological patients (103 of those had been diagnosed with proven or probable IA), and we evaluated their association with the risk of developing IA. The association of the most interesting markers of IA risk was then validated in a replication population, including 474 subjects (94 IA and 380 non-IA patients). Functional experiments were also performed to confirm the biological relevance of the most interesting markers. The meta-analysis of both populations showed that carriers of the ARNT2rs1374213G, CX3CR1rs7631529A, and CX3CR1rs9823718G alleles (where the RefSeq identifier appears as a subscript) had a significantly increased risk of developing IA according to a log-additive model (P value from the meta-analysis [PMeta] = 9.8 · 10-5, PMeta = 1.5 · 10-4, and PMeta =7.9 · 10-5, respectively). Haplotype analysis also confirmed the association of the CX3CR1 haplotype with AG CGG with an increased risk of IA (P = 4.0 · 10-4). Mechanistically, we observed that monocyte-derived macrophages (MDM) from subjects carrying the ARNTR2rs1374213G allele or the GG genotype showed a significantly impaired fungicidal activity but that MDM from carriers of the ARNT2rs1374213G and CX3CR1rs9823718G or CX3CR1rs7631529A alleles had deregulated immune responses to Aspergillus conidia. These results, together with those from expression quantitative trait locus (eQTL) data browsers showing a strong correlation of the CX3CR1rs9823718G allele with lower levels of CX3CR1 mRNA in whole peripheral blood (P = 2.46 · 10-7) and primary monocytes (P = 4.31 · 10-7), highlight the role of the ARNT2 and CX3CR1 loci in modulating and predicting IA risk and provide new insights into the host immune mechanisms involved in IA development.


Subject(s)
Aryl Hydrocarbon Receptor Nuclear Translocator/genetics , Aspergillus/immunology , Basic Helix-Loop-Helix Transcription Factors/genetics , CX3C Chemokine Receptor 1/genetics , Genetic Predisposition to Disease , Invasive Pulmonary Aspergillosis/genetics , Polymorphism, Single Nucleotide , Case-Control Studies , Genotype , Hematologic Diseases/complications , Humans , Risk Assessment
8.
Clin Microbiol Infect ; 26(5): 572-578, 2020 May.
Article in English | MEDLINE | ID: mdl-31446152

ABSTRACT

BACKGROUND: Both fracture-related infections (FRIs) and periprosthetic joint infections (PJIs) include orthopaedic implant-associated infections. However, key aspects of management differ due to the bone and soft tissue damage in FRIs and the option of removing the implant after fracture healing. In contrast to PJIs, research and guidelines for diagnosis and treatment in FRIs are scarce. OBJECTIVES: This narrative review aims to update clinical microbiologists, infectious disease specialists and surgeons on the management of FRIs. SOURCES: A computerized search of PubMed was performed to identify relevant studies. Search terms included 'Fracture' and 'Infection'. The reference lists of all retrieved articles were checked for additional relevant references. In addition, when scientific evidence was lacking, recommendations are based on expert opinion. CONTENT: Pathogenesis, prevention, diagnosis and treatment of FRIs are presented. Whenever available, specific data of patients with FRI are discussed. IMPLICATIONS: Management of patients with FRI should take into account FRI-specific features. Treatment pathways should implement a multidisciplinary approach to achieve a good outcome. Recently, international consensus guidelines were developed to improve the quality of care for patients suffering from this severe complication, which are highlighted in this review.


Subject(s)
Fractures, Bone/complications , Surgical Wound Infection/diagnosis , Surgical Wound Infection/therapy , Bacteria/isolation & purification , Bacteria/pathogenicity , Biomarkers/blood , Fracture Fixation/adverse effects , Fractures, Bone/surgery , Humans , Practice Guidelines as Topic , Prosthesis-Related Infections/diagnosis , Prosthesis-Related Infections/etiology , Prosthesis-Related Infections/prevention & control , Prosthesis-Related Infections/therapy , Surgical Wound Infection/etiology , Surgical Wound Infection/prevention & control
9.
Clin Microbiol Infect ; 24 Suppl 1: e1-e38, 2018 May.
Article in English | MEDLINE | ID: mdl-29544767

ABSTRACT

The European Society for Clinical Microbiology and Infectious Diseases, the European Confederation of Medical Mycology and the European Respiratory Society Joint Clinical Guidelines focus on diagnosis and management of aspergillosis. Of the numerous recommendations, a few are summarized here. Chest computed tomography as well as bronchoscopy with bronchoalveolar lavage (BAL) in patients with suspicion of pulmonary invasive aspergillosis (IA) are strongly recommended. For diagnosis, direct microscopy, preferably using optical brighteners, histopathology and culture are strongly recommended. Serum and BAL galactomannan measures are recommended as markers for the diagnosis of IA. PCR should be considered in conjunction with other diagnostic tests. Pathogen identification to species complex level is strongly recommended for all clinically relevant Aspergillus isolates; antifungal susceptibility testing should be performed in patients with invasive disease in regions with resistance found in contemporary surveillance programmes. Isavuconazole and voriconazole are the preferred agents for first-line treatment of pulmonary IA, whereas liposomal amphotericin B is moderately supported. Combinations of antifungals as primary treatment options are not recommended. Therapeutic drug monitoring is strongly recommended for patients receiving posaconazole suspension or any form of voriconazole for IA treatment, and in refractory disease, where a personalized approach considering reversal of predisposing factors, switching drug class and surgical intervention is also strongly recommended. Primary prophylaxis with posaconazole is strongly recommended in patients with acute myelogenous leukaemia or myelodysplastic syndrome receiving induction chemotherapy. Secondary prophylaxis is strongly recommended in high-risk patients. We strongly recommend treatment duration based on clinical improvement, degree of immunosuppression and response on imaging.


Subject(s)
Antifungal Agents/therapeutic use , Aspergillosis/diagnosis , Aspergillosis/drug therapy , Aspergillus/isolation & purification , Disease Management , Antibodies, Fungal/blood , Antifungal Agents/pharmacology , Aspergillosis/complications , Aspergillosis/immunology , Aspergillus/drug effects , Aspergillus/immunology , Biopsy/methods , Bronchoalveolar Lavage , Early Diagnosis , Flucytosine/pharmacology , Flucytosine/therapeutic use , Galactose/analogs & derivatives , Humans , Immunocompromised Host , Immunologic Tests , Invasive Pulmonary Aspergillosis/diagnosis , Itraconazole/pharmacology , Itraconazole/therapeutic use , Leukemia, Myeloid, Acute/complications , Leukemia, Myeloid, Acute/therapy , Magnetic Resonance Imaging , Mannans/analysis , Microbial Sensitivity Tests , Myelodysplastic Syndromes/complications , Myelodysplastic Syndromes/therapy , Nitriles/pharmacology , Nitriles/therapeutic use , Pyridines/pharmacology , Pyridines/therapeutic use , Tomography, X-Ray Computed , Triazoles/pharmacology , Triazoles/therapeutic use , Voriconazole/pharmacology , Voriconazole/therapeutic use
10.
Clin Microbiol Infect ; 23(11): 888.e1-888.e5, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28642141

ABSTRACT

OBJECTIVES: For adequate management and therapy of infective endocarditis (IE), identification of the causative pathogen is crucial but molecular testing results are not currently included in diagnostic criteria. The added diagnostic value and impact on antimicrobial therapy of 16S rRNA PCR and amplicon sequencing (16S rRNA PCR) performed on excised heart valves from patients with IE was evaluated alongside the effect of pre-operative antibiotics on the performance of blood culture (BC), valve culture (VC) and 16S rRNA PCR. METHODS: All patients undergoing valve surgery for definite or possible IE, according to modified Duke Criteria, were prospectively included from July 2013 up to and including June 2016. RESULTS: In all, 127 patients were included. Sensitivity for detecting the causative micro-organism in 120 post-operative definite IE patients was 26% for VC and 87% for BC and 16S rRNA PCR. 16S rRNA PCR, VC and BC were equally sensitive for different valve types and causative pathogens. In 27 (21%) definite IE patients, 16S rRNA PCR clarified discrepant culture results or was the only method identifying the causative pathogen. In 12 (10%) post-operative definite IE cases, molecular testing results influenced antimicrobial therapy. CONCLUSIONS: The very good performance characteristics, added diagnostic value and impact on antimicrobial therapy of molecular testing of heart valves should support the incorporation of molecular testing in diagnostic criteria and guidelines for IE.


Subject(s)
Anti-Infective Agents/therapeutic use , Endocarditis, Bacterial/diagnosis , Molecular Typing/methods , Polymerase Chain Reaction/methods , RNA, Ribosomal, 16S/genetics , Anti-Infective Agents/pharmacology , Bacteria/drug effects , Bacteria/genetics , DNA, Bacterial/genetics , Endocarditis, Bacterial/drug therapy , Endocarditis, Bacterial/microbiology , Humans , Predictive Value of Tests , Prospective Studies
11.
J Clin Microbiol ; 55(8): 2391-2399, 2017 08.
Article in English | MEDLINE | ID: mdl-28515220

ABSTRACT

Azole-resistant Aspergillus fumigatus is an increasing worldwide problem with major clinical implications. Surveillance is warranted to guide clinicians to provide optimal treatment to patients. To investigate azole resistance in clinical Aspergillus isolates in our institution, a Belgian university hospital, we conducted a laboratory-based surveillance between June 2015 and October 2016. Two different approaches were used: a prospective culture-based surveillance using VIPcheck on unselected A. fumigatus (n = 109 patients, including 19 patients with proven or probable invasive aspergillosis [IA]), followed by molecular detection of mutations conferring azole resistance, and a retrospective detection of azole-resistant A. fumigatus in bronchoalveolar lavage fluid using the commercially available AsperGenius PCR (n = 100 patients, including 29 patients with proven or probable IA). By VIPcheck, 25 azole-resistant A. fumigatus specimens were isolated from 14 patients (12.8%). Of these 14 patients, only 2 had proven or probable IA (10.5%). Mutations at the cyp51A gene were observed in 23 of the 25 A. fumigatus isolates; TR34/L98H was the most prevalent mutation (46.7%), followed by TR46/Y121F/T289A (26.7%). Twenty-seven (27%) patients were positive for the presence of Aspergillus species by AsperGenius PCR. A. fumigatus was detected by AsperGenius in 20 patients, and 3 of these patients carried cyp51A mutations. Two patients had proven or probable IA and cyp51A mutation (11.7%). Our study has shown that the detection of azole-resistant A. fumigatus in clinical isolates was a frequent finding in our institution. Hence, a rapid method for resistance detection may be useful to improve patient management. Centers that care for immunocompromised patients should perform routine surveillance to determine their local epidemiology.


Subject(s)
Antifungal Agents/pharmacology , Aspergillosis/diagnosis , Aspergillus fumigatus/isolation & purification , Azoles/pharmacology , Drug Resistance, Fungal , Microbiological Techniques/methods , Molecular Diagnostic Techniques/methods , Adult , Aged , Aged, 80 and over , Aspergillosis/microbiology , Aspergillus fumigatus/drug effects , Belgium , Female , Hospitals, University , Humans , Male , Middle Aged , Retrospective Studies
12.
Clin Microbiol Infect ; 23(10): 776.e1-776.e5, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28412383

ABSTRACT

OBJECTIVES: A prospective international multicentre surveillance study was conducted to investigate the prevalence and amphotericin B susceptibility of Aspergillus terreus species complex infections. METHODS: A total of 370 cases from 21 countries were evaluated. RESULTS: The overall prevalence of A. terreus species complex among the investigated patients with mould-positive cultures was 5.2% (370/7116). Amphotericin B MICs ranged from 0.125 to 32 mg/L, (median 8 mg/L). CONCLUSIONS: Aspergillus terreus species complex infections cause a wide spectrum of aspergillosis and the majority of cryptic species display high amphotericin B MICs.


Subject(s)
Aspergillosis/epidemiology , Aspergillosis/microbiology , Aspergillus/classification , Aspergillus/isolation & purification , Amphotericin B/pharmacology , Antifungal Agents/pharmacology , Aspergillus/drug effects , Epidemiological Monitoring , Europe/epidemiology , Humans , Microbial Sensitivity Tests , Prevalence , Prospective Studies
13.
Eur J Clin Microbiol Infect Dis ; 36(4): 649-655, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27858242

ABSTRACT

The primary aim of this study was to collect national epidemiological data on candidaemia and to determine the reporting time of species identification and antifungal susceptibility in clinical practice. During a 1-year period (March 2013 until February 2014), every first Candida isolate from each episode of candidaemia was included prospectively from 30 Belgian hospitals. Identification and susceptibility testing were performed according to local procedures and isolates were sent to the National Reference Center for Mycosis. Species identification was checked by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and internal transcribed spacer (ITS) sequencing in case no reliable identification was obtained by MALDI-TOF MS. Antifungal susceptibility testing was performed according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) methodology. A total of 355 isolates were retrieved from 338 patients. The mean incidence rate of candidaemia was 0.44 (range: 0.07 to 1.43) per 1000 admissions or 0.65 (range: 0.11 to 2.00) per 10,000 patient days. Candida albicans was most frequently found (50.4 %), followed by C. glabrata (27.3 %) and C. parapsilosis sensu lato (9.8 %). The overall resistance to fluconazole was 7.6 %, ranging from 3.9 % in C. albicans to 20.0 % in C. tropicalis. Only one C. glabrata isolate was resistant to the echinocandins. Four days after blood culture positivity, 99.7 % of the identifications and 90.3 % of the antifungal profiles were reported to the treating clinician. Candidaemia incidence rates differed up to 20-fold among Belgian hospitals; no clear factors explaining this difference were identified. The overall antifungal resistance rates were low but high azole resistance rates were recorded in C. tropicalis.


Subject(s)
Candida/isolation & purification , Candidemia/diagnosis , Candidemia/epidemiology , Drug Resistance, Fungal , Adolescent , Adult , Aged , Aged, 80 and over , Belgium/epidemiology , Candida/classification , Candida/genetics , Child , Child, Preschool , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Diagnostic Tests, Routine , Female , Hospitals , Humans , Incidence , Infant , Male , Microbial Sensitivity Tests , Middle Aged , Prospective Studies , Sequence Analysis, DNA , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Time Factors , Young Adult
14.
J Antimicrob Chemother ; 71(12): 3528-3535, 2016 12.
Article in English | MEDLINE | ID: mdl-27530755

ABSTRACT

OBJECTIVES: In patients with invasive aspergillosis (IA), fungal cultures are mostly negative. Consequently, azole resistance often remains undetected. The AsperGenius® multiplex real-time PCR assay identifies clinically relevant Aspergillus species and four resistance-associated mutations (RAMs; TR34/L98H/T289A/Y121F) in the Cyp51A gene. This multicentre study evaluated the diagnostic performance of this assay on bronchoalveolar lavage (BAL) fluid and correlated the presence of RAMs with azole treatment failure and mortality. METHODS: Stored BAL samples from patients with haematological diseases with suspected IA were used. BAL samples that were galactomannan/culture positive were considered positive controls for the presence of Aspergillus. Azole treatment failure and 6 week mortality were compared in patients with and without RAMs that had received ≥5 days of voriconazole monotherapy. RESULTS: Two hundred and one patients each contributed one BAL sample, of which 88 were positive controls and 113 were negative controls. The optimal cycle threshold cut-off value for the Aspergillus species PCR was <38. With this cut-off, the PCR was positive in 74/88 positive controls. The sensitivity, specificity, positive predictive value and negative predictive value were 84%, 80%, 76% and 87%, respectively. 32/74 BAL samples were culture negative. Azole treatment failure was observed in 6/8 patients with a RAM compared with 12/45 patients without RAMs (P = 0.01). Six week mortality was 2.7 times higher in patients with RAMs (50.0% versus 18.6%; P = 0.07). CONCLUSIONS: The AsperGenius® assay had a good diagnostic performance on BAL and differentiated WT from Aspergillus fumigatus with RAMs, including in culture-negative BAL samples. Most importantly, detection of RAMs was associated with azole treatment failure.


Subject(s)
Aspergillus fumigatus/genetics , Bronchoalveolar Lavage Fluid/microbiology , Cytochrome P-450 Enzyme System/genetics , Drug Resistance, Fungal , Fungal Proteins/genetics , Invasive Pulmonary Aspergillosis/diagnosis , Polymerase Chain Reaction/methods , Adolescent , Adult , Aged , Aged, 80 and over , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Aspergillus fumigatus/drug effects , Aspergillus fumigatus/isolation & purification , Azoles/pharmacology , Azoles/therapeutic use , Female , Genotyping Techniques/methods , Hematologic Diseases/complications , Humans , Invasive Pulmonary Aspergillosis/microbiology , Male , Middle Aged , Mutation , Retrospective Studies , Survival Analysis , Treatment Failure , Young Adult
15.
J Clin Microbiol ; 54(10): 2513-20, 2016 10.
Article in English | MEDLINE | ID: mdl-27440820

ABSTRACT

Infection is an important complication in patients with hematologic malignancies or solid tumors undergoing intensive cytotoxic chemotherapy. In only 20 to 30% of the febrile neutropenic episodes, an infectious agent is detected by conventional cultures. In this prospective study, the performance of broad-range PCR coupled with electrospray ionization time of flight mass spectrometry (PCR/ESI-MS) technology was compared to conventional blood cultures (BC) in a consecutive series of samples from high-risk hematology patients. In 74 patients, BC and a whole-blood sample for PCR/ESI-MS (Iridica BAC BSI; Abbott, Carlsbad, CA, USA) were collected at the start of each febrile neutropenic episode and, in case of persistent fever, also at day 5. During 100 different febrile episodes, 105 blood samples were collected and analyzed by PCR/ESI-MS. There was evidence of a bloodstream infection (BSI) in 36/105 cases (34%), based on 14 cases with both PCR/ESI-MS and BC positivity, 17 cases with BC positivity only, and 5 cases with PCR/ESI-MS positivity only. The sensitivity of PCR/ESI-MS was 45%, specificity was 93%, and the negative predictive value was 80% compared to blood culture. PCR/ESI-MS detected definite pathogens (Fusobacterium nucleatum and Streptococcus pneumoniae) missed by BC, whereas it missed both Gram-negative and Gram-positive organisms detected by BC. PCR/ESI-MS testing detected additional microorganisms but showed a low sensitivity (45%) compared to BC in neutropenic patients. Our results indicate a lower concordance between BC and PCR/ESI-MS in the neutropenic population than what has been previously reported in other patient groups with normal white blood cell distribution, and a lower sensitivity than other PCR-based methods.


Subject(s)
Bacteremia/diagnosis , Fever of Unknown Origin/diagnosis , Fungemia/diagnosis , Microbiological Techniques/methods , Neutropenia/complications , Polymerase Chain Reaction/methods , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Adult , Aged , Blood Culture , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Sensitivity and Specificity , Young Adult
17.
Clin Microbiol Infect ; 22(8): 704-10, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27234934

ABSTRACT

A challenge panel of bacterial strains useful for clinical laboratories to validate their European Committee on Antimicrobial Susceptibility Testing (EUCAST) antimicrobial susceptibility test (AST) system was established. A total of 117 strains, obtained from Belgian Reference Centres (n = 57) and from routine clinical samples (n = 60) was selected based on resistance pattern. These strains were analysed in seven different laboratories by three different automated AST systems (Vitek (n = 2), Phoenix (n = 2) and Microscan (n = 2)) and by disc diffusion from five different manufacturers (Rosco (n = 2), Becton-Dickinson (n = 2), Biomérieux (n = 1), Bio-rad (n = 1) and i2a (n = 1)). To select the challenge panel, selection criteria were set for categorical agreement between the different systems and the number of very major errors, major errors and minor errors. Very major and major errors for at least two antibiotics were observed in 43% of all strains, leading to the exclusion of these strains from the selected panel. In only 10% of all tested strains was there 100% categorical agreement for all antibiotics. Finally, 28 strains (14 Gram-positive and 14 Gram-negative) covering a wide spectrum of resistance mechanisms were selected. Pilot-testing of this challenge panel in 20 laboratories mainly confirmed the results of the validation study. Only six strains withheld for the pilot study could not be used as challenge strain due to an overall (very) major error rate of >5% for a particular antibiotic (n = 5) or for two antibiotics (n = 1). To conclude, this challenge panel should facilitate the implementation and use of EUCAST breakpoints in laboratories.


Subject(s)
Anti-Infective Agents/pharmacology , Microbial Sensitivity Tests/methods , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Bacterial Infections/diagnosis , Bacterial Infections/microbiology , Europe , Humans , Microbial Sensitivity Tests/standards , Pilot Projects , Reproducibility of Results , Sensitivity and Specificity
18.
Eur J Clin Microbiol Infect Dis ; 35(7): 1101-6, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27101352

ABSTRACT

Hantavirus infections, recently renamed 'hantavirus fever' (HTVF), belong to the most common but also most underestimated zoonoses in the world. A small number of reports described the so-called 'lipid paradox' in HTVF, i.e. the striking contrast between a very low serum total cholesterol and/or high-density lipoprotein cholesterol (HDLc), and a paradoxical concomitant hypertriglyceridaemia. In a prospective study, with patients being their own control after illness, we wanted to verify if this quick and easy 'bedside test' was robust enough to warrant a preliminary diagnosis of acute kidney injury (AKI) caused by HTVF. The study cohort consisted of 58 Belgian cases (mean age 44 years), admitted with varying degrees of AKI and of thrombocytopaenia, both characteristic for presumptive HTVF. All cases were sero-confirmed as having acute HTVF. At or shortly after hospital admission, a significant (p < 0.001) decrease of total cholesterol and HDLc was found in comparison with normalised levels in the same cohort, quantified a few days after spontaneous AKI recovery. Conversely, fasting triglyceride levels during HTVF infection were significantly (p < 0.001) higher during illness than after recovery. This 'lipid paradox' was most outspoken in severe HTVF cases, often accompanying, or even predicting, major kidney or lung complications. Thus, this 'bedside assessment' seems to hold even promise for presumptive diagnosis of more severe so-called 'hantavirus cardio-pulmonary syndrome' (HCPS) cases, mostly described hitherto in the New World. In more severe AKI cases, the mean total cholesterol was significantly lower (p = 0.02) than in milder cases, i.e. cases with peak serum creatinine levels of < 1.5 mg/dL. Thrombocytopaenia, generally accepted as the severity index in HTVF, appeared, moreover, significantly correlated with serum levels of total cholesterol (R = 0.52, p < 0.001) and with serum levels of HDLc (R = 0.45, p < 0.01). A link with the novel clinical entity of haemophagocytic syndromes, also characterised by manifest hypertriglyceridaemia, is discussed.


Subject(s)
Hantavirus Infections/diagnosis , Hantavirus Infections/virology , Lymphohistiocytosis, Hemophagocytic/diagnosis , Orthohantavirus , Adolescent , Adult , Aged , Biomarkers , Child , Diagnosis, Differential , Female , Hantavirus Infections/blood , Humans , Lipids/blood , Lymphohistiocytosis, Hemophagocytic/blood , Male , Middle Aged , Young Adult
19.
Eur J Clin Microbiol Infect Dis ; 35(6): 911-6, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27038443

ABSTRACT

Different reports of Pneumocystis jirovecii pneumonia (PcP) outbreaks on oncology and transplant units suggest the possibility of a person-to-person transmission. Based on these reports, we searched retrospectively for possible PcP clusters in UZ Leuven in 2013. A movement and transmission map was established for all patients (n = 21) with a positive PcP PCR on BAL fluid. BAL fluid samples from all patients with a positive PCR on the mitochondrial large subunit mRNA of P. jirovecii and possible cross exposure were typed with multilocus sequence typing (MLST). Five patients with a positive PcP PCR could have contact with another PcP patient. Another five patients with a weak positive PcP PCR on BAL fluid during the same period were also included. Based on the MLST typing of the BAL samples of these ten patients, there was no evidence of a PcP outbreak in UZ Leuven in 2013. MLST has proven to be a useful tool in genotyping and outbreak detection. From this case series, it could be concluded that current infection control precautions for P. jirovecii are appropriate in UZ Leuven. However, there is need for an international Pneumocystis database and more clarity in the geographic distribution of different P. jirovecii genotypes.


Subject(s)
Disease Outbreaks , Multilocus Sequence Typing , Pneumocystis carinii/classification , Pneumocystis carinii/genetics , Pneumonia, Pneumocystis/epidemiology , Pneumonia, Pneumocystis/microbiology , Genes, Fungal , Humans , Pneumonia, Pneumocystis/transmission , Population Surveillance , Seasons
20.
Clin Microbiol Infect ; 22(6): 571.e1-4, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26851656

ABSTRACT

The Subcommittee on Antifungal Susceptibility Testing (AFST) of the ESCMID European Committee for Antimicrobial Susceptibility Testing (EUCAST) has determined breakpoints for isavuconazole and Aspergillus and for itraconazole and Candida spp., released a new document summarizing existing and new minimum inhibitory concentration ranges for quality control strains and revised the method documents for yeast and mould susceptibility testing. This technical note is based on the EUCAST isavuconazole and itraconazole rationale documents, version 1.0 of the routine and extended internal quality control for antifungal susceptibility testing as recommended by EUCAST, and the E.Def 7.3, E.Def 9.2 and E.Def 9.3 method documents (http://www.eucast.org).


Subject(s)
Antifungal Agents/pharmacology , Fungi/drug effects , Microbial Sensitivity Tests/standards , Quality Control
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