Aspergillus Enzyme Immunoassay Research Articles

Comparative Analysis of the Clarus Aspergillus Galactomannan Enzyme Immunoassay Prototype for the Diagnosis of Invasive Pulmonary Aspergillosis in Bronchoalveolar Lavage Fluid

BackgroundGalactomannan (GM) testing using Platelia Aspergillus enzyme immunoassay (Platelia AGM) from bronchoalveolar lavage fluid (BALF) aids in early diagnosis of invasive pulmonary aspergillosis (IPA). Globally, only a minority of laboratories have the capability to perform on-site GM testing, necessitating accessible and affordable alternatives. Hence, we conducted a comparative evaluation of the new clarus Aspergillus GM enzyme immunoassay prototype (clarus AGM prototype) with Platelia AGM using BALF samples.MethodsThis is a single-center, prospective, cross-sectional study, where Platelia AGM testing was routinely performed followed by clarus AGM prototype testing in those with true positive or true negative AGM test results according to the 2020 EORTC/MSG and the 2024 FUNDICU consensus definitions. Descriptive statistics, ROC curve analysis, and Spearman’s correlation analysis were used to evaluate analytical performance of the clarus AGM prototype assay.ResultsThis study enrolled 259 adult patients, of which 53 (20%) were classified as probable IPA, while 206 did not fulfill IPA-criteria. Spearman's correlation analysis revealed a strong correlation between the two assays (rho = 0.727, p < 0.001). The clarus AGM prototype had a sensitivity of 96% (51/53) and a specificity of 74% (153/206) for differentiating probable versus no IPA when using the manufacturer recommended cut-off. ROC curve analysis showed an AUC of 0.936 (95% CI 0.901–0.971) for the clarus AGM prototype, while the Platelia AGM yielded an AUC of 0.918 (95% CI 0.876–0.959).ConclusionsClarus AGM prototype demonstrated a strong correlation and promising test performance, comparable to Platelia AGM, rendering it a viable alternative in patients at risk of IPA.

Performance of the JF5-Based Galactomannoprotein EIA Compared to the Lateral Flow Device and the Galactomannan EIA in Serum and Bronchoalveolar Lavage Fluid.

Early diagnosis of invasive aspergillosis is an important factor to improve survival but remains challenging. The detection of Aspergillus antigens is included in the consensus case definitions of the European Organization for Research and Treatment of Cancer and the National Institute of Allergy and Infectious Diseases Mycoses Study Group as a criterion of "probable" invasive aspergillosis. JF5, a mouse IgG3 monoclonal antibody detecting an Aspergillus mannoprotein, has already been implemented as a lateral flow device (LFD). Now, also a JF5-based enzyme-linked immunosorbent assay (EIA) is commercialized (Aspergillus specific galactomannoprotein [GP] EIA, Euroimmun Medizinische Labordiagnostika AG). In this study, we analyzed the diagnostic performance of GP in 63 bronchoalveolar lavage fluid (BALf) samples and 224 serum samples and compared it to performance of the galactomannan (GM) (Platelia Aspergillus enzyme immunoassay (EIA) (Bio-Rad, Marnes-la-Coquette, France)) and the JF5-based LFD (AspLFD; OLM Diagnostics, Newcastle Upon Tyne, United Kingdom). The diagnostic performance of GP and GM correlated well with both having high specificity. With an optimized cutoff threshold for positivity of 0.4-deviating from the 0.5 threshold recommended by the manufacturer-sensitivity of GP in serum is not significantly different than that of GM. However, in BALf sensitivity of GP is significantly less than for GM.

P499 A cross-sectional observational to assess the role of Bronchoalveolar lavage fluid galactomannan in the diagnosis of invasive pulmonary aspergillosis in non-neutropenic patients

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PMObjective: This study was done to assess the role of Bronchoalveolar lavage fluid (BALF) galactomannan (GM) in the diagnosis of invasive pulmonary aspergillosis (IPA) in non-neutropenic patients and to determine the optimal cut-off value of BALF GM for diagnosing IPA in non-neutropenic hosts.MethodsWe conducted a cross-sectional observational study on 96 non-neutropenic patients of age > 18 years with suspected pulmonary infections of fungal etiology. A detailed history of predisposing conditions was obtained and routine laboratory investigations with chest computerized (CT) tomography were performed. Fiberoptic bronchoscopy under local anesthesia and sedation was done using a video bronchoscope. Bronchoalveolar lavage was done from the segment or lobe of interest instilling 60-100 ml of saline withdrawn under low pressure and the sample was tested for a battery of investigations; fungal KOH smear; fungal culture; GM by Platelia Aspergillus enzyme immunoassay; and others required for diagnosis. A protected brush specimen and transbronchial lung biopsy were done wherever feasible. The yield from the BALF GM assay was compared with diagnosis based on definitions given by EORTC/MSG excluding host factors. Patients were classified into three groups namely non-IPA, probable IPA, and proven IPA. For statistical analysis, probable and proven IPA were taken as one group i.e., the IPA group. Mann-Whitney test and Chi-Square test along with Fisher's exact test were performed for inter-group comparison between quantitative and qualitative variables respectively. The receiver operator characteristic curve was used to establish a cut-off point of BALF GM and Serum GM for predicting IPA. Sensitivity, specificity, PPV, and NPV were calculated. The McNemar test was used for the comparison of sensitivity and specificity. Inter-rater kappa agreement was used to find the strength of agreement of BALF GM, BALF culture, and BALF DM.ResultsOut of 96, 1 was diagnosed with proven IPA, 34 were probable IPA cases and 61 were not IPA cases. Chronic kidney disease (CKD) as a risk factor was more common in IPA cases compared to non-IPA cases (25.7% vs. 8.2%, P-value .019). Chest CT showed cavity in a significant number of IPA patients compared to non-IPA cases (60% vs. 29.5%, P-value .003). BALF direct microscopy, culture, and serum GM had sensitivities < 60% but specificities close to 95%. BALF GM showed promising results with a sensitivity of 88.5% and specificity of 85.7% at cutoff value of 0.8.See Figures below.Conclusions: Our study highlights the magnitude of IPA in non-neutropenic hosts with unconventional risk factors like CKD, diabetes, and the need for increased vigilance for diagnosis of IPA in such patients. We suggest a lower cut-off value of BALF GM against 1 as in EORTC/MSG criteria and consider CKD as one of the risk factors for IPA.

P412 QuicGM Aspergillus Galactomannan Ag lateral flow assay as a practical aid to diagnose invasive Aspergillosis in high-risk hematology patients

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PMBackgroundEarly diagnosis of invasive aspergillosis (IA) is an important factor to improve survival, but it remains challenging. QuicGM Aspergillus Galactomannan Ag Lateral Flow Assay (LFA) is based on a fluorescence immunochromatography test using a monoclonal antibody to identify Aspergillus galactomannan antigen in serum and bronchoalveolar lavage fluid.MethodsIn this study, we analyzed the diagnostic performance of QuicGM in 120 serum samples of high-risk hematology patients [41 cases of proven (n = 4) and probable (n = 37) IA and 79 equally high-risk controls] and compared it to performance of the galactomannan (GM) [Platelia Aspergillus enzyme immunoassay (ELISA) (Bio-Rad, Marnes-la-Coquette, France)]. Probable cases defined by a positive Biorad GM in serum were also included in the cohort.ResultsUsing the same cut-off of 0.5, QuicGM was positive in 22 cases versus GM in 21 cases. However, QuicGM was false positive in 11 controls with GM only in 1 control. These false positive samples remained positive upon repeated testing with the QuicGM. The test results of QuicGM and GM correlated well with a Spearman's correlation coefficient of 0.80 (P <.001). McNemar test showed no significant difference between both tests (P = 1) and Cohen's kappa coefficient was 0.65 (CI 0.49-0.81), suggesting a substantial strength of agreement.QuicGM sensitivity (using 0.5 cutoff) was 54% versus 51% for GM. Specificity was 86% for QuicGM versus 99% for GM. Positive predictive value (PPV) was only 67% for QuicGM versus 95% for GM. Combining GM and QuicGM in serum increased sensitivity to 59%. Youden index of QuicGM in the cohort was 0.39. Using this cutoff, sensitivity was 66% and specificity was 80%. When using a higher cutoff of 0.6 for the QuicGM, specificity increased to 94% and PPV to 78%, at the cost of a decrease in sensitivity to 44%.DiscussionIncluding probable cases defined by a positive Biorad GM in serum could have led to a bias in favor of the GM.With the cutoff suggested by the company, there was a notable decrease in specificity and PPV for the QuicGM. The need to adjust this cut-off must be questioned. With the implementation of LFAs in the EORTC-MSGERG criteria, one usually strives for the same cutoff of 0.5, to assure a practical approach. However, we must remain thoughtful about slight differences in these tests. They all have their own IgG and IgM built. Caution is needed more in the setting of diagnosis than in screening.More knowledge must be obtained regarding how different hospital laboratories have implemented the LFAs.ConclusionDiagnostic performances of QuicGM and Biorad GM correlate well.Further research is necessary regarding the optimal cutoff index.

Sandwich-type homogeneous chemiluminescence immunoassay based on nanoparticle toward detection of Aspergillus galactomannan antigen

Aspergillus species continue to be an important cause of life-threatening infection in immunocompromised patients and galactomannan (GM) is a popular biomarker in the diagnosis of invasive aspergillosis (IA). Here we developed and validated an amplified luminescent proximity homogenous assay-linked immunosorbent assay (AlphaLISA) for serum and bronchoalveolar fluid (BALF) GM based on this approach. Technological processes and reaction conditions were optimized. Study assessments included reproducibility, accuracy, stability, and cross reactivity experiments. Method comparisons with the commercial Platelia Aspergillus enzyme immunoassay (Bio-Rad Laboratories) were performed using 201 clinical serum and BALF samples. Under the optimized conditions, the total runtime of the AlphaLISA method was 40 min with simple operation. The percent coefficient variations (CVs%) were lower than 15%, and the recoveries were in the range of 90–110%. Of note, the proposed assay exhibited acceptable stability and did not display cross-reactivity with non-Aspergillus pathogens. Compared with the results from the Platelia kit, there was a satisfied overall qualitative agreement of 97.5% and overall quantitative correlation coefficient of 0.59. In all, we have successfully developed an alternative novel homogeneous nanoparticle-based immunoassay, which has shorter incubation time and easier protocol than the ones of conventional ELISA. It could serve as an alternative to the well-established Platelia assay for measurement of GM in serum and BALF.

Can Aspergillus fumigatus conidia cause false-positive results in the galactomannan enzyme immunoassay test?

Several factors can cause false-positive results in the galactomannan (GM) test; however, others remain unknown. Presently, the impact of airborne contamination by Aspergillus conidia during enzyme-linked immunosorbent assay (ELISA) remains uninvestigated. We studied 12 A. fumigatus isolates. Fungal conidia were serially diluted and tested for GM detection using the Platelia® Aspergillus enzyme immunoassay (EIA). The conidia concentration required for an EIA-positive result was 4.8 × 103 (median). This is the first study to evaluate the impact of environmental contamination on the Platelia® Aspergillus EIA assay. Only massive contamination can interfere with GM optical readings, suggesting that environmental contamination does not cause false-positive test results.

Levofloxacin-Induced Acute Eosinophilic Pneumonitis: A Case Report and Review

SESSION TITLE: Critical Care 1 SESSION TYPE: Affiliate Case Report Slide PRESENTED ON: Sunday, October 29, 2017 at 10:45 AM - 12:00 PM INTRODUCTION: Acute eosinophilic pneumonia (AEP) is a rare and potentially fatal entity that requires prompt recognition. While the mechanism of AEP remains unclear, AEP may occur after exposure to toxins, radiation therapy, and drugs. A review of the literature identified only 2 other cases of suspected levofloxacin induced AEP. In this report, we describe a patient with AEP shortly after a course of levofloxacin, who had complete resolution of symptoms and peripheral eosinophilia after steroid therapy. CASE PRESENTATION: Patient was a 49 year old Asian man with seasonal allergies severe enough to require immunotherapy and a recent URI who presented with fever and dyspnea on exertion. He had recently completed a 7 day course of daily levofloxacin 500mg two days prior to presentation. Social history was unremarkable as he denied recent travel, exposure to animals, or changes to his home environment. He presented to the ED with hypoxemia requiring 100% non-rebreather (PaO2 88). Exam was remarkable for bilateral wheezing. Lab studies were significant for a leukocytosis to 15K with an eosinophilia to 19%, and an elevated IgE level of 2229. CT chest revealed bilateral asymmetric ground glass opacities. Empiric antibiotics and steroids were initiated. Direct visualization of the airways via flexible bronchoscopy was notable for thick mucus plugs involving all bronchopulmonary segments. BAL fluid analysis revealed 45% eosinophils. Analysis for typical infectious etiologies including, Tuberculosis, Mycoplasma spp, Legionella spp, Streptococcus, HIV, and Influenza were all negative. Cultures of the blood, sputum, and BAL fluid were unrevealing. Specialized tests including Aspergillus enzyme immunoassay (EIA), IgE, and IgG levels were negative, (1-3)-β-d-glucan assay, Strongyloides EIA were also negative. Dyspnea improved after the third day of methylprednisolone and hypoxemia improved on day five. DISCUSSION: A definitive diagnosis of drug-induced AEP is made with: (1) febrile illness <5 days duration, (2) diffuse bilateral pulmonary infiltrates, (3) hypoxemia (4) bronchoalveolar lavage >25% eosinophils, (5) temporal relationship with exposure, (6) clinical improvement after cessation of drug; and (7) recurrence of symptoms with drug rechallenge. The exact pathophysiology of the drug reaction remains unknown, as there is evidence to suggest both Type I or III hypersensitivities. The incidence of fluoroquinolone hypersensitivity is very low <1 in 50,000. To our knowledge, this is only the third case of eosinophilic pneumonitis secondary to levofloxacin. CONCLUSIONS: While fluoroquinolone antibiotics are well studied, widely prescribed drugs, it is important for physicians to quickly recognize the rare complication of eosinophilic pneumonitis. Reference #1: Steiger D, et al. Ciprofloxacin-induced acute interstitial pneumonitis. Eur Respir J. 2004 Reference #2: Fujimori K, et al. [Levofloxacin-induced eosinophilic pneumonia]. Nihon Kokyuki Gakkai Zasshi. DISCLOSURE: The following authors have nothing to disclose: Christian Castaneda, Christine Feng, Alexander Feldberg, Christopher Lee, Olumayowa Abe No Product/Research Disclosure Information

Non-Invasive Methods to Diagnose Fungal Infections in Pediatric Patients with Hematologic Disorders.

BackgroundInvasive fungal infection (IFIs) is a major infectious complication in immunocompromised patients. Early diagnosis and initiation of antifungal therapy is important to achieve the best outcome.ObjectivesThe current study aimed to investigate the incidence of IFIs and evaluate the diagnostic performance of non-invasive laboratory tests: serologic (β-D-glucan, galactomannan) and molecular (nested polymerase chain reaction) tests to diagnose fungal infections in hematologic pediatric patients.Patients and MethodsIn a cross-sectional study from October 2014 to January 2015, 321 blood samples of 62 pediatric patients with hematologic disorders and at high risk for fungal infections were analyzed. Non-invasive tests including the Platelia Aspergillus enzyme immunoassay (EIA) to detect galactomannan antigen, Glucatell for β–D–glucan and nested PCR to detect Candida and Aspergillus species-specific DNA were used in a weekly screening strategy.ResultsTwenty six patients (42%) were considered as proven and probable IFIs, including 3 (5%) proven and 23 (37%) probable cases. Eighteen patients (29%) were considered as possible cases. The sensitivity, specificity, positive and negative predictive values for galactomannan test in 26 patients with proven and probable fungal infections were 94.4%, 100%, 100% and 94.7%; for β-D-glucan test 92.3%, 77.7%, 85%, 87.5% and for nested-PCR were 84.6%, 88.8%, 91.7% and 80%, respectively.ConclusionsThe rate of IFIs in pediatric patients with hematologic disorders is high, and sample collection from the sterile sites cannot be performed in immunocompromised patients. Detection of circulating fungal cell wall components and DNA in the blood using non-invasive methods can offer diagnostic help in patients with suspected IFIs. Their results should be interpreted in combination with clinical, radiological and microbiological findings.

Role of galactomannan assay in bronchoalveolar lavage fluid in the diagnosis of invasive aspergillosis in high risk patients with hematological disorders

Introduction: Invasive aspergillosis (IA) is the most frequent invasive fungal infection occurring in high risk patients with haematological disorders and also an important cause of morbidity and mortality in them. Lungs comprise the primary site of IA in the vast majority of cases, and the most frequently occurring form of IA. Early diagnosis followed by early initiation of therapy improves outcome. The current culture based diagnostic methods are insensitive and slow. Detection of Aspergillus galactomannan (GM) in serum using the platelia Aspergillus enzyme immunoassay (GM EIA) represents sensitive, non-culture-based tool for the early diagnosis of IA. Recent studies have shown that during IPA, GM is released earlier and in higher concentration in the BAL fluid than in serum. Thus, an early and accurate diagnosis of IPA can be reached by detecting antigen in BAL samples. Materials and Methods: Thirty consecutive high risk patients with haematological disorders satisfying the inclusion and exclusion criteria according to EORTC-MSG diagnostic criteria and undergoing indoor treatment were recruited between November 2013 and December 2014 into the study. In all the patients, bronchoalveolar lavage (BAL) fluid GM and serum GM assays were assayed. Results: The diagnostic accuracy of the two tests was measured by calculating the sensitivity, specificity, predictive values and receiver operating characteristic curve (ROC). The optimal BAL GM index for diagnosing probable and possible IPA was >1.00 OD, resulting in a sensitivity and specificity of 93.75% and 78.57% respectively. As per ROC curve, when the optimal BAL GM index for the diagnosis of probable and possible invasive pulmonary aspergillosis (IPA) was OD >0.5, it resulted in sensitivity and specificity of 50% and 71.43% respectively. BAL GM was thus found to have a significantly higher sensitivity as compared to serum GM. Conclusion: In all high-risk patients with haematological disorders where the clinical and radiological findings favour the possibility of invasive pulmonary aspergillosis, conducting a GM assay in BAL fluid sample is far more rewarding than carrying out the traditional serum GM assay. BAL GM has a high diagnostic accuracy when correlated with the EORTC/MSG diagnostic criteria, and this high diagnostic yield is useful in obviating the unnecessary widespread use and abuse of empirical antifungal therapy in patients with IPA.

A Clinical Study of Acquired Immunodeficiency Syndrome Associated Penicillium Marneffei Infection from a Non-Endemic Area in China.

ObjectiveTo investigate the clinical characteristics, diagnosis, treatment and prognosis of penicilliosis among the patients with acquired immunodeficiency syndrome (AIDS) in non-endemic areas of China, and then to discuss its incubation period and the diagnostic performance of serum galactomannan test for penicilliosis.MethodsMedical records and travel histories of penicilliosis patients in Zhongnan hospital from January 2006 to December 2013, and the interval from when the patients left the endemic area to the onset of the disease was analyzed. Serum galactomannan levels of penicilliosis patients and AIDS patients with fever were measured by the Platelia Aspergillus Enzyme Immunoassay Kit.ResultsA total of 47 AIDS-associated penicilliosis were confirmed by fungal culture, which accounted for 4.8% of 981 AIDS-related admissions. The sensitivity and specificity of serum galactomannan test for penicilliosis were 95.8% (23/24) and 90.9% (30/33), respectively, (cutoff index = 1.0). Two independent predictors for early mortality (death within 12 weeks) of the patients (21.3%, 10/47) were a delayed diagnosis and no treatment with antifungal therapy. Among 14 patients who became ill after leaving endemic areas, ten patients presented with the onset symptoms within 12 months (from 11 days to 360 days). We found a patient living with asymptomatic P. marneffei fungemia who had not received any antifungal therapy until 18 months’ follow up.ConclusionsThe co-infection of P. marneffei and HIV was not uncommon in the non-endemic areas of penicilliosis in China. There exists a latent form of infection for P. marneffei. The incubation period of penicilliosis may be quite different from one patient to another. In AIDS patients, the serum galactomannan test has utility for the diagnosis of penicilliosis. When patients with penicilliosis/AIDS were diagnosed early and treated with standardized antifungal therapy and combined antiretroviral therapy, their prognosis improved.

Serum galactomannan assay for the diagnosis of invasive aspergillosis in children with haematological malignancies

Diagnostic efficacy of Galactomannan (GM) assay for invasive aspergillosis (IA) is variably reported. Data from developing countries are scant. Children with haematological malignancies and fever were enrolled prospectively. Blood sample for GM was drawn on the day of admission; levels were measured with Platellia Aspergillus enzyme immunoassay. Diagnostic criteria were adapted from EORTC-MSG-2002. Proven, probable and possible episodes were considered as the disease group. One hundred febrile episodes in 78 patients were evaluated. The mean age was 6.1 years. Majority (75%) episodes were in patients with acute lymphoblastic leukaemia. One episode each was diagnosed with proven and probable IA, while 23 were diagnosed with possible IA. Best results were obtained with a cut-off value of 1.0, with sensitivity, specificity, positive and negative predictive value of 60%, 93%, 75 and 87 respectively. The sensitivity dropped to 40%, at cut-off value of 1.5 and specificity was 38%, at a cut-off of 0.5. A higher value of GM correlated with pulmonary nodules (P = 0.037) and mortality (P = 0.001). GM assay is adjunctive to clinical/radiological evidence. A negative GM assay may not reassure the physician against the use of amphotericin in patients with febrile neutropenia, as it does not exclude the diagnosis of clinically relevant other fungal infections, particular mucormycosis.

Erratum

Transplant Infectious DiseaseVolume 14, Issue 3 p. 332-332 ErratumFree Access Erratum This article corrects the following: Lack of intra-laboratory reproducibility in using Platelia Aspergillus enzyme immunoassay test for detection of Aspergillus galactomannan antigen I. Oren, I. Avidor, H. Sprecher, Volume 14Issue 1Transplant Infectious Disease pages: 107-109 First Published online: July 6, 2011 First published: 08 June 2012 https://doi.org/10.1111/j.1399-3062.2012.00758.xAboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Response to: Lack of intra-laboratory reproducibility in using Platelia Aspergillus enzyme immunoassay test for detection of Aspergillus galactomannan antigen A. Bizzini, O. Marchetti, P. Meylan Transpl Infect Dis 2012: 14: 218–219 DOI: 10.1111/j.1399-3062.2011.00707.x Reference 1Oren I, Avidor I, Sprecher H. Lack of intra-laboratory reproducibility in using Platelia Aspergillus enzyme immunoassay test for detection of Aspergillus galactomannan antigen. Transpl Infect Dis 2012; 14 (1): 107– 109. Volume14, Issue3June 2012Pages 332-332 ReferencesRelatedInformation

Bronchoalveolar lavage galactomannan for the diagnosis of chronic pulmonary aspergillosis

Diagnosing chronic pulmonary aspergillosis (CPA) is complicated, and there are limited data available regarding the identification of galactomannan (GM) in clinical specimens to assist the detection of this infection. The purpose of this study was to evaluate the detection of GM in bronchoalveolar lavage fluid (BALF) and serum and to assess its utility for diagnosing CPA. We retrospectively reviewed the diagnostic and clinical characteristics of 144 patients, with and without CPA, in Nagasaki University Hospital, Japan, whose BAL and serum specimens were examined for the presence of GM. The Platelia Aspergillus enzyme immunoassay (PA EIA) was performed according to the manufacturer's instructions. The mean values of BALF GM antigen were 4.535 (range, 0.062-14.120) and 0.430 (range, 0.062-9.285) in CPA (18) and non-CPA (126) patients, respectively. The mean values of serum GM antigen were 1.557 (range, 0.232-5.397) and 0.864 (range, 0.028-8.956) in CPA and non-CPA patients, respectively. PA EIA of BALF is superior to the test with serum, with the optimal cut-off values for BALF and serum of 0.4 and 0.7, respectively. The sensitivity and specificity of PA EIA in BALF at a cut-off of 0.4 were 77.2% and 77.0%, respectively, whereas with serum at a cut-off of 0.7, they were 66.7% and 63.5%, respectively. GM testing using BALF showed reasonable sensitivity and specificity as compared to that using serum. Thus, assessing GM levels in BALF may enhance the accuracy of diagnosing CPA.

Clinical utility and prognostic value of galactomannan in neutropenic patients with invasive aspergillosis

Invasive aspergillosis (IA) is a major cause of morbidity and mortality in profoundly neutropenic patients. Delayed diagnosis and therapy may lead to poor outcomes. AimsThe objective of this study was to assess the performance characteristics of the galactomannan (GM) assay in serum and bronchoalveolar lavage specimens for the diagnosis of IA in neutropenic patients with hematological malignancies. We also evaluated the prognostic outcome. Patients and methodsA total of 1198 serum samples and 42 BAL from 235 neutropenic patients were tested with a GM elisa platelia test. We used Cox modeling of time to 6- and 12-week mortality for GM level at the time of diagnosis (GM0) and GM decay in the week following diagnosis in proven and probable IA patients with more than two GM values. ResultsThere were three proven, 55 probable, and four possible cases of IA. The sensitivity and specificity of the GM test were 96.8% and 82.4% respectively. In BAL samples, sensitivity was 86% and the specificity 93%. BAL GM was more sensitive than microscopy (22.2%) and BAL culture (38.9%). Among patients with proven/probable IA, serum and BAL GM were in agreement for 92.8% of paired samples. The hazard ratio (HR) of GM0 and 1-week GM decay per unit increase in Aspergillus enzyme immunoassay (EIA) was 1.044 (95% CI, 0.738 to 1.476) and 0.709 (95% CI, 0.236 to 2.130) respectively. ConclusionWe found good correlation between the GM0 and GM decay combination and outcome of IA patients. The GM is a useful tool for diagnosis and monitoring of IA.

Strong Association between Respiratory Viral Infection Early after Hematopoietic Stem Cell Transplantation and the Development of Life-Threatening Acute and Chronic Alloimmune Lung Syndromes

Alloimmune lung syndromes (allo-LS), including idiopathic pneumonia syndrome, bronchiolitis obliterans syndrome, and bronchiolitis obliterans organizing pneumonia, are severe complications after hematopoietic stem cell transplantation (HSCT). In our cohort of 110 pediatric patients, 30 had allo-LS (27.3%), 18 with ideopathic pneumonia syndrome and 12 with bronchiolitis obliterans syndrome. Multivariate analysis showed that respiratory viral infection early after HSCT is an important predictor for the development of allo-LS (P <.0001). This was true for all viruses tested. In multivariate analysis, allo-LS was the only predictor for higher mortality (P = .04). Paradoxically, prolonged administration of immunosuppressive agents because of acute graft-versus-host disease had a protective effect on the development of allo-LS (P = .004). We hypothesize that early infection of the respiratory tract with a common cold virus makes the lungs a target for alloimmunity.

Lung Abscess due to Clostridium baratii Infection in a Patient with Invasive Pulmonary Aspergillosis

Clostridial pleuropulmonary infections are rare; most of these infections are attributed to Clostridium perfringens (1), and none involving C. baratii have been reported. We describe here a fatal case of C. baratii lung abscess superimposed on invasive pulmonary aspergillosis. A 47-year-old man was diagnosed with myelodysplastic syndrome with refractory anemia and excess blasts in December 2005. The disease course was complicated by disseminated Mycobacterium avium complex infection and invasive pulmonary aspergillosis. The patient underwent allogeneic hematopoietic stem cell transplantation in May 2006. One year later, he was admitted for leukemia relapse associated with febrile neutropenia. Chest radiography and computed tomography (CT) displayed multiple small opacities on the right upper and lower and left upper lung fields. Compared with chest CT results seen 1 year before, only the lesion on the left upper lung had increased in size (Fig. ​(Fig.1A).1A). Low-grade fever persisted despite treatment with imipenem and voriconazole. Serum Aspergillus antigen results (Platelia Aspergillus enzyme immunoassay; Bio-Rad Laboratories) were negative. The lesion on the left lung progressed rapidly within 1 month (Fig. ​(Fig.1B).1B). Follow-up chest CT results showed an abscess with a thick wall (Fig. 1C and D). In August 2007, the patient was admitted to an intensive care unit (ICU) because of acute respiratory failure. A sonography-guided transthoracic lung biopsy was performed on the second ICU day. Pathology examination of the lung biopsy sample disclosed narrow, dichotomous, and septated hyphae compatible with Aspergillus spp. Cultures of the lung biopsy sample and aspirates of the lung abscess as well as blood cultures all yielded C. baratii that was susceptible to penicillin, chloramphenicol, metronidazole, and cefmetazole but was resistant to clindamycin by a disk diffusion test. The patient's hemodynamics deteriorated, and the patient died of multiple organ failure on the twelfth ICU day. FIG. 1. (A) CT scan of the chest on admission, showing a small faint patch at the left upper lung field (LULF) and old fibrotic changes at the right upper lung field. (B to D) Follow-up chest radiography 1 month later disclosed a mass lesion at the LULF (B), ... The genus Clostridium has more than 150 species, but fewer than 20 are associated with human diseases (5, 7). Members of the genus are mainly natural inhabitants of the human intestinal tract, and their disease spectra in humans are broad (7). C. baratii has attracted limited attention because of its lack of overt pathogenesis and failure to produce lethal toxin. Its most striking clinical feature is its neurotoxogenesis, type F botulism in infants (4) and in adults (3, 4). However, C. baratii pulmonary infection in adults has never been previously reported in the literature. We speculate that the development of a lung abscess caused by C. baratii in this case may be closely related to the patient's leukemia relapse with persistent neutropenia and invasive pulmonary aspergillosis. The hyphae of Aspergillus species tend to invade blood vessels, which in turn leads to local thrombosis and tissue infarction (2, 6). Simultaneously, clostridial bacteremia originating from the disruption of the gastrointestinal mucosa results in seeding into the lung, with subsequent formation of lung abscess. The infection is refractory to antimicrobials in the face of tissue infarction despite the use of antimicrobial agents with in vitro activity against C. barati. In conclusion, among high-risk hosts, the rapid progression of fungal pneumonia into lung abscesses may suggest the presence of a superimposed infection due to an anaerobic bacterial species such as C. barati.

Intravenous PLASMA-LYTE as a Major Cause of False-Positive Results of Platelia Aspergillus Test for Galactomannan Detection in Serum

Galactomannan (GM) detection by the Platelia Aspergillus (PA) enzyme immunoassay (Bio-Rad, France) is a test widely used for the early diagnosis of invasive aspergillosis (IA) in hematooncological patients. False-positive results for this test were reported by several authors, associated mainly with

Aspergillus Galactomannan Antigen in the Bronchoalveolar Lavage Fluid for the Diagnosis of Invasive Aspergillosis in Lung Transplant Recipients

The clinical utility of Platelia Aspergillus enzyme immunoassay (EIA) for galactomannan (GM) antigen detection in bronchoalveolar lavage (BAL) for the diagnosis of invasive aspergillosis (IA) in lung transplant recipients is not known. BAL fluid samples from consecutive lung transplant recipients who underwent bronchoscopy were prospectively analyzed for GM. A total of 333 BAL samples from 116 patients were tested. Invasive aspergillosis was documented in 5.2% (6/116) of the patients. Samples analyzed included 9 BALs from two patients with proven IA, 19 BALs from four patients with probable IA, and 305 BALs from 110 patients without IA. At the index cutoff value of > or =0.5, the sensitivity was 60%; specificity was 95%, with positive and negative likelihood ratios of 14 and 0.41, respectively. Increasing the index cutoff value to > or =1.0 yielded a sensitivity of 60%, a specificity of 98%, and the positive and negative likelihood ratios of 28 and 0.40, respectively. Two of six patients with IA receiving antifungal prophylaxis had false-negative results. A Platelia EIA index cut-off > or =1.0 in the BAL fluid in a lung transplant recipient with a compatible clinical illness may be considered as suggestive of IA.

Contamination by Cardboard Particles as a Cause of False-Positive Results for Aspergillus Galactomannan Enzyme Immunoassays

Galactomannan (GM) detection by the Platelia Aspergillus enzyme immunoassay is widely used for diagnosing invasive aspergillosis. A major problem with the detection of circulating GM is the occurrence of false-positive results due to the cross-reactivity of the test with antigens other than

Optimization of the Cutoff Value for the Aspergillus Double-Sandwich Enzyme Immunoassay

Many health care centers worldwide use the Platelia Aspergillus enzyme immunoassay (PA-EIA; Bio-Rad Laboratories) for diagnosis of invasive aspergillosis (IA). A cutoff optical density (OD) index of 1.5 was originally recommended by the manufacturer, but in practice, most institutions use lower cutoff values. Moreover, a cutoff OD index of 0.5 was recently approved in the United States. In the present study, we set out to optimize the cutoff level by performing a retrospective analysis of PA-EIA values for samples that had been obtained prospectively from adult patients at risk for IA at 2 European health care centers. In total, 239 treatment episodes were included of which there were 19 episodes of proven IA and 19 episodes of probable IA. Per-episode and per-test analyses and receiver operating characteristic curves were used to determine the optimal cutoff value. In the per-episode analysis, lowering the cutoff OD index for positivity from 1.5 to 0.5 increased the overall sensitivity by 21% (from 76.3% to 97.4%) but decreased the overall specificity by 7% (from 97.5% to 90.5%). Requiring 2 consecutive samples with an OD index > or = 0.5 resulted in the highest test accuracy, with an improved positive predictive value. At a cutoff OD index of 0.5, the antigen test result was positive during the week before conventional diagnosis in 65% of cases and during the week of diagnosis in 79.5% of cases. A cutoff OD index of 0.5--identical to the approved cutoff in the United States--improves the overall performance of the PA-EIA for adult hematology patients.