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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Invasive mould infections are a major cause of morbidity and mortality in hematopoietic stem cell transplant recipients (HSCT). Allogeneic HSCT recipients are at substantially higher risk than autologous HSCT recipients. Although neutropenia following the conditioning regimen remains an important risk factor for opportunistic fungal infections, most cases of invasive mould infection in allogeneic HSCT recipients occur after neutrophil recovery in the setting of potent immunosuppressive therapy for graft-versus-host disease. Invasive aspergillosis is the most common mould infection. However, there has been an increased incidence of less common non-Aspergillus moulds that include zygomycetes, Fusarium sp., and Scedosporium sp. Reflecting a key need, important advances have been made in the antifungal armamentarium. Voriconazole has become a new standard of care as primary therapy for invasive aspergillosis based on superiority over amphotericin B. There is significant interest in combination therapy for invasive aspergillosis pairing voriconazole or an amphotericin B formulation with an echinocandin. There have also been advances in novel diagnostic methods that facilitate early detection of invasive fungal infections that include galactomannan and beta-glucan antigen detection and PCR using fungal specific primers. We review the epidemiology, diagnosis, and management of invasive mould infection in HSCT, with a focus on allogeneic recipients. We also discuss options for prevention and early treatment of invasive mould infections.
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PMID:Review of epidemiology, diagnosis, and treatment of invasive mould infections in allogeneic hematopoietic stem cell transplant recipients. 1683 Jan 86

Candida albicans is a common cause of nosocomial infections whose virulence depends on the reversible switch from blastoconidia to hyphal forms. Neutrophils (or polymorphonuclear leukocytes (PMNs)) readily clear blastoconidia by phagocytosis, but filaments are too long to be ingested. Mechanisms regulating immune recognition and response to filamentous fungal pathogens are not well understood, although known risk factors for developing life-threatening infections are neutropenia or defects in the NADPH oxidase system. We show human PMNs generate a respiratory burst response to unopsonized hyphae. Ab specific for beta-glucan, a major component of yeast cell walls, blocks this response, establishing beta-glucan as a key molecular pattern recognized by PMNs in response to C. albicans. This study also elucidates recognition and signaling mechanisms used by PMNs in response to beta-glucan under conditions where phagocytosis cannot occur. Human PMNs adhered to immobilized beta-glucan and released an efficient plasma membrane respiratory burst. Ab blockade of the integrin complement receptor 3 (CD11b/CD18) significantly inhibited both of these functions. Furthermore, we show a role for p38 MAPK and actin but not protein kinase C zeta in generating the respiratory burst to beta-glucan. Taken together, results show that beta-glucan in C. albicans hyphae is accessible to PMNs and sufficient to support an innate immune response.
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PMID:Beta-glucan is a fungal determinant for adhesion-dependent human neutrophil functions. 1714 67

Invasive aspergillosis is a serious and often fatal infection in patients who are neutropenic or have undergone solid organ or stem cell transplantation. Delayed diagnosis and therapy may lead to poor outcomes. Diagnosis may be facilitated by a test for galactomannan antigen detection using an enzyme immunoassay. Other rapid methods for diagnosis include (1-->3)-beta-D: -glucan determination and polymerase chain reaction. The sensitivity and specificity of galactomannan antigenemia testing in serum and bronchoalveolar lavage specimens are high in patients with hematological malignancy, neutropenia, and receipt of stem-cell transplants. False positivity can be seen with concomitant administration of some antibiotics and infection by fungi other than Aspergillus.
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PMID:Diagnosis of invasive aspergillosis by galactomannan antigenemia detection using an enzyme immunoassay. 1819 5

The performance of the Fungitell assay was investigated in 100 patients with haematological malignancy undergoing chemotherapy who developed antibiotic-unresponsive neutropenic fever (AUNF). Serum beta-D-glucan (BG) concentrations were significantly elevated on the first day of AUNF and all subsequent alternate days to day 10 in 38 patients who developed an invasive fungal infection (IFI) compared to 42 patients remaining free of such infections. The mean and median values of BG were 171.9+/-29.6 and 95.8 pg ml(-1), respectively, for patients with IFI and 64.4+/-17.1 and 32.9 pg ml(-1) for patients with only AUNF (P<0.0001). The differences remained significant over the 10 days despite antifungal therapy. The occurrence of > or =2 sequential concentrations of > or =80 pg ml(-1) ('positive' test) was found to give the best overall option for diagnosis, with an accuracy of 81.3%, sensitivity of 86.8%, positive predictive value of 76.7% and negative predictive value of 86.5%. Of the patients with an IFI, 78% developed a positive test at or before the clinical diagnosis was made -- this occurred at a mean (range) of 1.25 (-14 to +14) days prior to the IFI diagnosis. By starting sampling of blood from the first day of neutropenia rather than from the first day of AUNF, 50% of the patients with subsequent IFI would have been identified 5 days earlier. Increasing sampling to daily from alternate-day frequency did not further improve this earlier timing of an IFI diagnosis. A greater proportion of patients with persistent high levels of BG without overt IFI had severe enterocyte damage or mucositis than those with lower levels of BG without IFI (P=0.002). If the results of the initial BG test had been acted on to change antifungal therapy, discontinuation would have been inappropriate in 30% of patients and would have delayed definitive antifungal therapy. Although the findings for the cohort of patients studied are very useful, there is inter-patient variability in the test's performance. An holistic diagnostic approach is therefore necessary to interpret the test results optimally. Future studies should address this in further detail as well as the impact of empirical antifungal drug use and patient outcome.
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PMID:Assessment of the clinical utility of serial beta-D-glucan concentrations in patients with persistent neutropenic fever. 1828 90

This review summarizes the current status and diagnostic-therapeutic challenges in febrile neutropenia. Patients with neutropenia-associated infections have a poor prognosis. A large meta-analysis of trials assessing prophylactic antibiotics has shown significant survival benefits; clinical significance of resistance is unclear. Administering broad-spectrum antibiotics to established febrile neutropenic patients has become selective, vancomycin is withheld unless absolutely necessary, and low-risk patients are identified with biological markers. Such patients are now managed with oral antibiotics at home or even without antibiotics. Protracted prolonged neutropenia is the setting par excellence for invasive fungal infections. Conventional amphotericin B administered to such risk patients reduces the incidence of fungal infections. New antifungal drugs have heightened efficacy and lowered toxicity. Novel antifungal diagnostic tests include imaging, particularly the CT "halo" sign (aspergillosis), and serology (glucan, galactomannan), and provide earlier diagnosis and treatment and better outcomes. Negative tests may indicate withholding antifungal therapy. High intermittent dosing of liposomal amphotericin B seems as safe and as effective as standard dosing regimens, but at half the drug acquisition cost. The use of nonantibiotic agents has offered alternative management strategies. Recombinant interleukin-11 reduces bacteremia, through a cytoprotective mechanism on the gut. rhIL-11 releases C-reactive protein and causes shedding of soluble TNF receptor-1, modulating the immunological milieu and the systemic inflammatory response. Other candidate molecules include RANTES and long-pentraxin 3. Recombinant growth factors reduce febrile episodes, permitting completion of chemotherapy, increase overall survival, and minimize infection mortality.
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PMID:Febrile neutropenia. 1883 9

The diagnostic performance and usefulness of the Platelia antigen and antibody test (Bio-Rad) was investigated in a prospective study of haematological patients at risk for invasive Candida infections. Among 100 patients, 86 were eligible, of whom invasive candidiasis (IC) occurred in 12 (14%), according to the criteria of the European Organization for Research and Treatment of Cancer/Mycoses Study Group. These included candidaemia due to Candida albicans (one patient) or Candida tropicalis (four patients), and hepatosplenic candidiasis (seven patients). The comparator group of 74 patients included 50 with febrile neutropenia alone and 24 with mould infections. A strategy was developed to determine diagnostic cut-offs from receiver operating characteristic curves with maximal sensitivity and, given this sensitivity, maximal specificity, both being greater than 0. In this patient population, these values were 0.25 ng ml(-1) for mannan (M) and 2.6 arbitrary units ml(-1) for anti-mannan (AM), which are lower than those recommended by the manufacturer. All patients developed at least one positive diagnostic M or AM result during the 10 days of persistent febrile neutropenia (PFN). The optimal overall performance was found when two consecutive positive tests for both M and AM were used [sensitivity, specificity, positive predictive value and negative predictive value (NPV) (95 % confidence intervals) of 0.73 (0.39-0.94), 0.80 (0.69-0.89), 0.36 (0.17-0.59) and 0.95 (0.86-0.99), respectively]. There was a positive correlation of M with beta-D-glucan (r=0.28, P=0.01). The first positive M test was found up to a mean+/-sd of 8.8+/-8.5 (range 2-23) days prior to a clinical/mycological diagnosis of IC. Day-to-day variation in quantitative M levels was high. High-level AM responses were delayed until leucopenia resolved. The low specificities of the test performance may have been due to some of the comparator patients having subclinical Candida infections as evidenced by the high incidence of colonization among them (60% had a colonization index of >or=0.5). The high NPVs suggest that the tests may be particularly useful in excluding IC. It is feasible to explore the use of serial measurements of M and AM as part of a broader diagnostic strategy for selecting PFN patients to receive antifungal drug therapy.
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PMID:Prospective evaluation of mannan and anti-mannan antibodies for diagnosis of invasive Candida infections in patients with neutropenic fever. 1936 22

Patients with neutropenia lasting for more than 10d, who develop fever and pulmonary infiltrates, are at risk of treatment failure under conventional broad-spectrum antibacterial therapy. Filamentous fungi are predominant causes of failure, however, multi-resistant gram-negative rods such as Pseudomonas aeruginosa or Stenotrophomonas maltophilia may be involved. Prompt addition of mould-active systemic antifungal therapy, facilitated by early thoracic computed tomography, improves clinical outcome. Non-culture-based diagnostic procedures to detect circulating antigens such as galactomannan or 1,3-beta-d-glucan, or PCR techniques to amplify circulating fungal DNA from blood, bronchoalveolar lavage or tissue specimens, may facilitate the diagnosis of invasive pulmonary aspergillosis. CT-guided bronchoalveolar lavage is useful in order to identify causative microorganisms such as multidrug-resistant bacteria, filamentous fungi or Pneumocystis jiroveci. For pre-emptive antifungal treatment, voriconazole or liposomal amphotericin B is preferred. In patients given broad-spectrum azoles for antifungal prophylaxis, non-azole antifungals or antifungal combinations might become first choice in this setting. Antifungal treatment should be continued for at least 14 d before non-response and treatment modification are considered. Microbial isolates from blood cultures, bronchoalveolar lavage or respiratory secretions must be critically interpreted with respect to their aetiological relevance for pulmonary infiltrates.
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PMID:Diagnosis and antimicrobial therapy of lung infiltrates in febrile neutropenic patients: Guidelines of the infectious diseases working party of the German Society of Haematology and Oncology. 1946 84

Invasive Candida infections are associated with a significant morbidity and mortality. Detection of circulating biomarkers has been shown to precede conventional diagnostic methods, which is important in improving outcome. We investigated the performance of multiple biomarkers using Candida antigen and anti-Candida antibody detection systems of Platelia and Serion and beta-d-glucan detection in serial serum samples from patients, treated for leukemia, with invasive candidiasis. The performance of single assays and combined detection appeared different for patients with 1 or more episodes of neutropenia and is therefore related to the phase of therapy for the underlying leukemia of the patient. These new insights may help to optimize the diagnostic strategies for the diagnosis of invasive candidiasis.
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PMID:Value of Candida serum markers in patients with invasive candidiasis after myeloablative chemotherapy. 1963 Oct 94

Echinocandins act by inhibiting 1,3-beta-D-glucan synthesis in the fungal cell wall. The three licensed agents in this class, namely anidulafungin, caspofungin and micafungin, have a favourable pharmacological profile. These agents are narrow spectrum with clinically relevant activity against Candida and Aspergillus spp. Several trials have established the non-inferiority of these agents over existing agents in the treatment of invasive fungal infections. Caspofungin is also licensed for empirical antifungal therapy of presumed fungal infections in patients with febrile neutropenia. This paper reviews the literature on echinocandins.
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PMID:The echinocandins: three useful choices or three too many? 1994 13

While anti-cancer chemotherapy has improved the survival of patients with hematologic malignancies, it has also exposed such patients to the risk of life-threatening infection due to neutropenia. In intensive chemotherapy for leukemia, invasive aspergillosis resulting in death is infrequently observed. In such cases, aggressive diagnostic and therapeutic intervention is required. Herein, we report a case of Aspergillus liver abscesses in a patient with acute monoblastic leukemia. The patient presented with febrile neutropenia and concomitantly with an elevated serum beta-D: -glucan level during chemotherapy. The abscesses were finally diagnosed by liver biopsy. Although antifungal monotherapy of voriconazole or liposomal amphotericin B, both of which are recommended for invasive aspergillosis, showed a poor response, when combined with micafungin, an echinocandin, both had a highly favorable effect against the infection. Therefore, our clinical experience suggests that the serum test is useful for the rapid diagnosis of invasive aspergillosis, especially in deep tissues, and that combination antifungal therapy with micafungin should be considered when initial monotherapy for fungal infection shows an insufficient effect.
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PMID:Successful treatment of Aspergillus liver abscesses in a patient with acute monoblastic leukemia using combination antifungal therapy including micafungin as a key drug. 2035 80


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