Evidence Of Invasive Aspergillosis Research Articles

Assessing Differences between Clinical Isolates of Aspergillus fumigatus from Cases of Proven Invasive Aspergillosis and Colonizing Isolates with Respect to Phenotype (Virulence in Tenebrio molitor Larvae) and Genotype.

The fungus Aspergillus fumigatus, the cause of invasive aspergillosis (IA), is a serious risk to transplant patients and those with respiratory diseases. Host immune suppression is considered the most important factor for the development of IA. Less is known about the importance of fungal virulence in the development of IA including the significance of variation between isolates. In this study, isolates of A. fumigatus from cases diagnosed as having proven IA or colonisation (no evidence of IA) were compared in assays to measure isolate virulence. These assays included the measurement of radial growth and protease production on agar, sensitivity to UV light and oxidative stressors, and virulence in Tenebrio molitor (mealworm) larvae. These assays did not reveal obvious differences in virulence between the two groups of isolates; this provided the impetus to conduct genomic analysis. Whole genome sequencing and analysis did not allow grouping into coloniser or IA isolates. However, focused analysis of single nucleotide polymorphisms revealed variation in three putative genes: AFUA_5G09420 (ccg-8), AFUA_4G00330, and AFUA_4G00350. These are known to be responsive to azole exposure, and ccg-8 deletion leads to azole hypersensitivity in other fungi. A. fumigatus virulence is challenging, but the findings of this study indicate that further research into the response to oxidative stress and azole exposure are required to understand the development of IA.

Acute isolated Aspergillus appendicitis in pediatric leukemia

Aspergillus is a widespread fungus in the environment, usually invades through the respiratory tract. Invasive aspergillosis is a fatal disseminated infection in immunocompromised hosts. Appendicitis occurs scarcely in patients with leukemia. We report a case of Aspergillus appendicitis that underwent an urgent appendectomy. An 11-year-old boy received the diagnosis of acute myeloid leukemia, because of the bone pain and results of the bone marrow study. He obtained a complete remission after cancer chemotherapy and received peripheral blood stem cell transplantation from a histocompatible sibling. Leukemia relapsed 5 months post-transplant. Induction therapy with etoposide, cytarabine and mitoxantrone was started on Candida prophylaxis. Fifteen days after the end of chemotherapy, he presented with febrile neutropenia and abdominal pain, that did not respond to broad-spectrum antibiotics. Serum levels of C-reactive protein, β-D-glucan and procalcitonin were unremarkable. Computed tomography scan revealed a swollen appendix and the adjacent tissue inflammation. An urgent appendectomy led to a tentative diagnosis of Aspergillus appendicitis based on the histopathological findings of many fungal hyphal forms. Panfungal polymerase chain reaction using DNA extracted from the lesion determined the pathogen of Aspergillus niger. There was no evidence of invasive aspergillosis. During the prolonged anti-fungal therapy, he achieved a remission of leukemia and underwent the second hematopoietic cell transplantation. To our knowledge, Aspergillus appendicitis was reported to occur in 5 leukemia patients. Four of them survived after appendectomy and one died from intestinal perforation. Early surgical intervention is mandatory for a cure of Aspergillus appendicitis in neutropenic patients on Candida prophylaxis.

Late histopathologic characteristics of critically ill COVID-19 patients: Different phenotypes without evidence of invasive aspergillosis, a case series.

PurposePathological data of critical ill COVID-19 patients is essential in the search for optimal treatment options.Material and methodsWe performed postmortem needle core lung biopsies in seven patients with COVID-19 related ARDS. Clinical, radiological and microbiological characteristics are reported together with histopathological findings.Measurement and main resultsPatients age ranged from 58 to 83 years, five males and two females were included. Time from hospital admission to death ranged from 12 to 36 days, with a mean of 20 ventilated days. ICU stay was complicated by pulmonary embolism in five patients and positive galactomannan on bronchoalveolar lavage fluid in six patients, suggesting COVID-19 associated pulmonary aspergillosis. Chest CT in all patients showed ground glass opacities, commonly progressing to nondependent consolidations. We observed four distinct histopathological patterns: acute fibrinous and organizing pneumonia, diffuse alveolar damage, fibrosis and, in four out of seven patients an organizing pneumonia. None of the biopsy specimens showed any signs of invasive aspergillosis.ConclusionsIn this case series common late histopathology in critically ill COVID patients is not classic DAD but heterogeneous with predominant pattern of organizing pneumonia. Postmortem biopsy investigations in critically COVID-19 patients with probable COVID-19 associated pulmonary aspergillosis obtained no evidence for invasive aspergillosis.

262. Assessment of Serum Galactomannan Test Results of Pediatric Patients with Hematologic Malignancies According to Different Threshold Levels and Consecutive Positivity in Terms of Invasive Aspergillosis Diagnosis: Cross-Sectional Research in a Tertiary Care Hospital

BackgroundThe aim of this study was to evaluate the diagnostic utility of serum galactomannan (GM) test by investigating the impact of positivity according to different threshold levels and consecutiveness in terms of invasive aspergillosis (IA) in pediatric hematology-oncology patients.MethodsPositive GM test results between January 2015 and August 2017 were reviewed, retrospectively. The children with hematological malignancies and GM positivity were included in the study and grouped according to the presence of IA. Impact of single and consecutive (3-day interval) GM positivity on IA diagnosis were evaluated according to different galactomannan index (GMI) threshold values of >0.5, >0.7, >1.0, and >1.5.ResultsThere were 104 positive GM results from 70 patients. Forty-one patients (58.6%) had no clinical evidence of IA and categorized as the non-IA group. Invasive aspergillosis diagnosis was identified in 29 (41.4%) of the patients; 2 of them were proven and 27 were probable. Demographic characteristics and clinical findings of the patients were reviewed in Tables 1 and 2. According to different cutoff GMI values, the number of positive results was 104 for >0.5, 76 for >0.7, 57 for >1.0 and 32 for >1.5. The PPVs were low at a single GMI of >0.5 (39.4%) and reached to 50.0% with single GMI of >1.0. There was not a statistically significant difference between IA and non-IA groups in terms of different thresholds of a single GM positivity (P > 0.05) (Table 3). The number of two consecutive positive results was 34 for GMI of >0.5, 20 for GMI of >0.7, 13 for GMI of >1.0 and 4 for GMI of >1.5. In the IA group, GM positivity of consecutive results was significantly higher than non-IA group (P < 0.05). The PPVs of two consecutive positive results for GMI >0.5, GMI >0.7, GMI >1.0, and GMI >1.5 were 58.8%, 65.0%, 84.6%, and 100.0%, respectively. The effect of the GMI increase between two consecutive GM results on IA diagnosis (GM2-GM1 >0.5) was also evaluated and the PPV was found 53.8% without a statistical significance between two groups (Table 4).ConclusionWhen evaluated with consecutive GM positivity, the GM assay would have higher PPVs independently from the GMI cutoff value chosen. Since it may be more effective on IA diagnosis, consecutive sampling should be performed in pediatric patients at high risk. Disclosures All authors: No reported disclosures.

The misleading effect of serum galactomannan testing in high-risk haematology patients receiving prophylaxis with micafungin

ObjectivesTo investigate the performance of the routine serum galactomannan (sGM) assay in the diagnosis of invasive aspergillosis (IA) in high-risk haematology patients receiving prophylaxis with micafungin. MethodsRetrospective study including all haematological patients who received prophylaxis with micafungin during high-risk IA episodes (neutropenic patients after chemotherapy for acute myeloid leukaemia/myelodysplastic syndrome; allogeneic haematopoietic stem-cell transplantation during early neutropenic phase or graft-versus-host disease requiring high prednisone doses) and for whom at least one sGM result was available. Episodes were classified as follows: true-positive (positive GM in the context of IA), false-positive (positive GM result in patients who had no evidence of IA), true-negative (negative GM test results and no IA), or false-negative (negative GM test in the context of IA). Non-evaluable patients were excluded. ResultsAmong 146 evaluable episodes, four were true-positive in the context of probable breakthrough IA (incidence of breakthrough IA, 2.7%); 111/146 high-risk episodes (76%) were considered true-negative and 31/146 (21.2%) were considered false-positive. No false-negative episodes were detected. All but one of the false-positive episodes were detected in surveillance GM tests, leading to high-resolution CT scans in eight cases (8/31; 25.8%), all of which were negative. The positive predictive and negative predictive values of sGM for surveillance and diagnostic approaches were 3.2% (1/31) and 100% (110/110) and 75% (3/4) and 100% (1/1), respectively. ConclusionsSurveillance of asymptomatic patients receiving prophylaxis with micafungin using sGM is unnecessary, because the results are either negative or false-positive. However, sGM remains useful in the diagnosis of breakthrough IA in symptomatic patients during prophylaxis.

Invasive aspergillosis in patients with underlying liver cirrhosis: a prospective cohort study.

The aim of this study was to determine the prevalence of invasive aspergillosis (IA) in patients with liver cirrhosis and the performance of serum galactomannan (GM) screening. Patients with decompensated liver cirrhosis and patients with compensated liver cirrhosis presenting with fever and/or respiratory symptoms were prospectively enrolled. All patients were screened by serum GM twice weekly irrespective of clinical signs and symptoms. Positive serum GM triggered work-up consisting of chest computed tomography and in case of pathological findings bronchoscopy. 150 patients were included in the study. Two (1.3%) had probable, one (0.7%) had possible, and 147 (98%) had no evidence of IA. Both patients with probable IA had compensated liver cirrhosis. Sensitivity for serum GM screening for probable versus no IA was 0.5 (95% CI, 0.09-0.91), specificity 0.97 (95% CI: 0.92-0.99), negative predictive value 0.99 (95% CI, 0.96-0.99) and positive predictive value (PPV) 0.17 (95% CI, 0.01-0.64). PPV was 0.5 (95% CI, 0.03-0.98) in patients with clinical suspicion of IA. In conclusion, prevalence of IA in patients with liver cirrhosis seems to be low. Targeted GM testing in case of clinical suspicion of IA may be associated with markedly higher PPVs when compared to universal GM screening in patients with liver cirrhosis.

Evaluation of Serum Galactomannan Enzyme Immunoassay at Two Different Cut-offs for the Diagnosis of Invasive Aspergillosis in Patients with Febrile Neutropenia

Background: Invasive aspergillosis (IA) is an increasingly common and fatal opportunistic fungal infection in patients with haematological diseases. Early diagnosis is difficult as mycological culture techniques have low sensitivity and the radiological tools have low specificity. Galactomannan enzyme immunoassay (GEI) detects galactomannan in the human serum with a reported sensitivity and specificity between 30% and 100%. Aims: The aim of this study was to analyse the role of GEI in diagnosis of IA in patients with febrile neutropenia and to evaluate the role of GEI in the diagnosis of IA as per the revised (2008) European Organization for Research and Treatment of Cancer–Mycoses Study Group (EORTC–MSG) criteria at two different optical density (OD) cut-offs of 0.5 and 1.0. Setting: This prospective study was conducted in Safdarjung Hospital, New Delhi, India. Methods: GEI testing was performed in adult patients of febrile neutropenia with evidence of IA. Results at two different OD indices (ODIs) of 0.5 and 1.0 were analysed. The evaluation of the diagnostic parameter, that is, GEI was measured in terms of sensitivity, specificity and positive and negative predictive value and was validated with the revised (2008) EORTC–MSG diagnostic criteria of IA. Results: One hundred and eleven patients had evidence of IA, of which 79 patients were GEI positive when cut-off ODI was 0.5, whereas with cut-off ODI 1.0, 55 patients were GEI positive. Conclusion: ODI of 1.0 should be considered as positive while in patients with OD between 0.5 and 1.0, repeat sampling from the patient is recommended.

Galactomannan testing and Aspergillus PCR in same-day bronchoalveolar lavage and blood samples for diagnosis of invasive aspergillosis.

In recent years galactomannan antigen testing (GM) and also Aspergillus PCR have become increasingly important for diagnosis of invasive aspergillosis (IA). Whether or not these tests need to be performed with bronchoalveolar lavage fluid (BALF; i.e., primary site of infection), or testing of blood samples is sufficient, remains, however, a matter of debate. We evaluated the diagnostic performance of GM ELISA, and Aspergillus PCR by using BALF samples and blood samples obtained at the same day from a total of 53 immunocompromised patients (16 with probable/proven IA and 37 with no evidence of IA according to the revised EORTC/MSG criteria; 38 patients with hematological malignancies were prospectively enrolled at the Medical University of Graz, Austria, 15 patients with mixed underlying diseases at the Mannheim University Hospital). Patients with possible IA were excluded from this analysis. A total of 34/53 (64%) of all patients and 12/16 (75%) of patients with probable/proven IA received mold-active antifungal prophylaxis/therapy at the time of the BALF procedure. Sensitivities of GM and Aspergillus PCR were 38% and 44% in BALF, and 31% and 0% in blood, respectively. Best sensitivity (75%) for detecting proven/probable IA was achieved when BALF Aspergillus PCR, BALF GM (>1.0 ODI), BALF-culture and serum-GM (>0.5 ODI) were combined (specificity 95%). In conclusion, sensitivities of the evaluated diagnostic tests-when interpreted on their own-were low in BALF and even lower in blood, sensitivities increased markedly when diagnostic tests were combined.

Multicenter Comparison of Serum and Whole-Blood Specimens for Detection of Aspergillus DNA in High-Risk Hematological Patients

Samples from patients at high risk for invasive aspergillosis (IA) were prospectively collected and analyzed for the presence of molecular markers of fungal infection. Serum specimens were screened for galactomannan and Aspergillus DNA, and whole-blood specimens were screened only for Aspergillus DNA. Fungal infections were categorized according to the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group, National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) criteria. Forty-seven cases (proven and probable IA) and 31 controls (no evidence of IA) were selected retrospectively for this case-control study, comprising 803 samples, in order to determine the performance of whole-blood PCR, serum PCR, and serum galactomannan testing. Although no single assay was able to detect every case of IA, a combination of different assays provided the best performance. There was no significant difference between the use of whole-blood and serum specimens for PCR-based diagnosis of IA, but there was a trend for whole blood to be more sensitive (85% versus 79%) and to yield an earlier positive result (36 days versus 15 days) than for serum. However, DNA extraction from serum specimens is easier and faster than that from whole-blood specimens, and it allows the same specimen to be used for both galactomannan and PCR assays. In conclusion, the appropriate sample type for DNA extraction should be determined by the local requirements and the technical platforms available at each individual center. A combination of biomarker tests offered the best diagnostic utility for detecting IA.

The Role of Bronchoalveolar Lavage Galactomannan in the Diagnosis of Pediatric Invasive Aspergillosis

: Molecular biomarkers such as the galactomannan assay are of increasing interest in clinical settings for diagnosis of invasive aspergillosis (IA). The use of bronchoalveolar lavage galactomannan (BAL GM) is being validated in adult populations, but has not been systematically evaluated in pediatric patients. : A retrospective analysis was performed of patients for whom GM assays from BAL were submitted between November 1, 2006 and November14, 2007 at Childrens Hospital Los Angeles. Medical charts were reviewed and patients were categorized as having no, possible, probable, and proven IA, per established definitions. : Of 85 pediatric patients who had a BAL GM submitted during the study, 59 were immunocompromised. Three patients were identified as having proven IA, 6 had probable IA, 37 had possible IA, and 39 had no evidence of IA; 38 had a concurrent serum GM performed. A positive, linear correlation was established between BAL and serum GM, using OD index values (rho = 0.48, P = 0.002). Among immunocompromised patients, receiver operating characteristic curves demonstrated an optimal BAL GM OD cut-off value of 0.87, that yielded a sensitivity for probable/proven IA of 78% and a specificity of 100%. At 0.87, the positive and negative predictive values among immunocompromised patients were 58% and 96%, respectively. : We found a correlation between BAL GM values and a diagnosis of IA. We also noted a linear relationship between serum and BAL GM values. Receiver operating characteristic curves obtained from our pediatric data validate the current cut off for serum and suggest a possible cut off for BAL specimens.

Outcome and Medical Costs of Patients with Invasive Aspergillosis and Acute Myelogenous Leukemia–Myelodysplastic Syndrome Treated with Intensive Chemotherapy: An Observational Study

Invasive aspergillosis (IA) is a leading cause of mortality in patients with acute leukemia. Management of IA is expensive, which makes prevention desirable. Because hospital resources are limited, prevention costs have to be compared with treatment costs and outcome. In 269 patients treated for acute myelogenous leukemia-myelodysplastic syndrome (AML-MDS) during 2002-2007, evidence of IA was collected using high-resolution computed tomography and galactomannan measurement in bronchoalveolar lavage fluid specimens. IA was classified on the basis of updated European Organization for Research and Treatment of Cancer/Mycoses Study Group definitions. Outcome of infection was registered. Diagnostic and therapeutic IA-related costs, corrected for neutropenia duration, were comprehensively analyzed from a hospital perspective. Voriconazole treatment was given orally from day 1 if possible. A total of 80 patients developed IA; 48 (18%) had probable or proven infection, and 32 (12%) had possible IA. Seventy-three patients were treated with voriconazole; 55 (75%) took oral voriconazole from day 1. In patients with IA, the mortality rate 12 weeks after starting antifungal therapy was 22% (16 of 73 patients). The overall mortality rate, registered 12 weeks after neutrophil recovery from the last dose of antileukemic treatment, was 26% in patients with IA versus 16% in patients without IA (P = .08), reflecting an IA-attributable mortality rate of 10%. In a Cox regression analysis, IA was associated with an increased mortality risk (hazard ratio, 2.4; 95% confidence interval, 1.3-4.4). Total IA-related costs increased to euro 8360 and euro 15,280 for patients with possible and probable or proven IA, respectively, compared with patients without IA (P<.001). Early diagnosis and treatment of IA with oral voriconazole result in acceptable mortality rates. Nevertheless, IA continues to have substantial attributable mortality combined with a major impact on hospital resource use, so effective prevention in high-incidence populations has the potential to save lives and costs.

Quick and reliable galactomannan detection in crude minced lung specimens from haematological patients with suspected invasive fungal infection: results from a case series

Invasive aspergillosis (IA) is the leading direct or contributory cause of death in patients with haematological malignancies. Early diagnosis remains difficult and often elusive due the heterogeneity of clinical presentations and the low sensitivity of both histological examination and cultures of specimens obtained from patients at risk. We report two cases of IA, both of which lacked both histological and cultural evidence of IA from pulmonary specimens. In both patients, detection of galactomannan (GM) by enzyme immunoassay (EIA) on pulmonary tissue homogenates led to the diagnosis of IA, which was confirmed by Aspergillus DNA (real time PCR). In conclusion, we provide preliminary evidence that lung homogenates may be prepared for GM EIA assays, which may contribute to quick diagnosis of IA on otherwise negative samples. We feel that our results open up the opportunity of a prospective and comparative evaluation of this diagnostic technique.

Prospective Aspergillus Galactomannan Antigen Testing in Pediatric Hematopoietic Stem Cell Transplant Recipients

The galactomannan (GM) assay is an approved noninvasive test for detection of invasive aspergillosis (IA) that has been validated in adult patients with hematologic malignancies who are undergoing bone marrow transplantation. There have been few studies with this assay in pediatric patients, but early reports suggest that there may be differences in the performance such that false-positive GM tests in pediatric patients are more common than in adult patients. We performed a prospective study in pediatric hematopoietic stem cell transplant recipients with twice-weekly sampling for GM detection during the highest risk periods of neutropenia and graft-versus-host disease. We analyzed 826 serum samples from 64 patients, including 15 serum samples from one patient diagnosed with probable IA according to defined criteria. Twenty of 811 samples tested positive on repeat testing (specificity, 97.5%; 95% CI: 96.2-98.4%) including samples from 8 of 63 patients without clinical evidence of IA according to study criteria (specificity, 87.3%; 95% CI: 76.9-93.4%). Eleven patients received piperacillin/tazobactam therapy, and 4 of the 11 patients had a positive assay result coinciding with the dates of piperacillin/tazobactam administration. When samples from these patients were excluded, specificity increased to 98.4% (95% CI: 97.2-99.1%) by sample and to 91.5% (95% CI: 81.6-96.3%) by patient. The GM assay holds promise for early, noninvasive diagnosis of IA in high-risk children and false-positive results were not common or unexplainable. This study supports further validation of this assay in a large-scale, pediatric-dedicated format.

False positivity for Aspergillus antigenemia related to the administration of piperacillin/tazobactam

Background Invasive aspergillosis is a challenge to the internist, and difficulties diagnosing the disease remain an everlasting problem. Methods We reviewed the data of 65 patients with hematological malignancies and aplastic anemia who were tested for the galactomannan (GM) antigen of Aspergillus between March and November 2003. Results GM antigen levels were false-positive in at least two consecutive samples in 5 out of 23 patients who did not have evidence of invasive aspergillosis (false positivity rate of 21.7%) but who received concomitant piperacillin/tazobactam (P/T) compared to 0 of 28 patients who did not. Discussion The use of P/T in febrile, neutropenic patients decreases the specificity of GM antigen testing, which may lead to incorrect and unnecessary attempts at diagnosis and therapy.

Detection of galactomannan antigenemia in patients receiving piperacillin-tazobactam and correlations between in vitro, in vivo, and clinical properties of the drug-antigen interaction.

Recent case reports describe patients receiving piperacillin-tazobactam who were found to have circulating galactomannan detected by the double sandwich enzyme-linked immunosorbent assay (ELISA) system, leading to the false presumption of invasive aspergillosis. Since this property of piperacillin-tazobactam and galactomannan ELISA is not well understood, we investigated the in vitro, in vivo, and clinical properties of this interaction. Among the 12 reconstituted antibiotics representing four classes of antibacterial compounds that are commonly used in immunocompromised patients, piperacillin-tazobactam expressed a distinctively high level of galactomannan antigen in vitro (P = 0.001). After intravenous infusion of piperacillin-tazobactam into rabbits, the serum galactomannan index (GMI) in vivo changed significantly (P = 0.0007) from a preinfusion mean baseline value of 0.27 to a mean GMI of 0.83 by 30 min to slowly decline to a mean GMI of 0.44 24 h later. Repeated administration of piperacillin-tazobactam over 7 days resulted in accumulation of circulating galactomannan to a mean peak GMI of 1.31 and a nadir of 0.53. Further studies revealed that the antigen reached a steady state by the third day of administration of piperacillin-tazobactam. Twenty-six hospitalized patients with no evidence of invasive aspergillosis who were receiving antibiotics and ten healthy blood bank donors were studied for expression of circulating galactomannan. Patients (n = 13) receiving piperacillin-tazobactam had significantly greater mean serum GMI values (0.74 +/- 0.14) compared to patients (n = 13) receiving other antibiotics (0.14 +/- 0.08) and compared to healthy blood bank donors (0.14 +/- 0.06) (P < 0.001). Five (38.5%) of thirteen patients receiving piperacillin-tazobactam had serum GMI values > 0.5 compared to none of thirteen subjects receiving other antibiotics (P = 0.039) and to none of ten healthy blood bank donors (P = 0.046). These data demonstrate that among antibiotics that are commonly used in immunocompromised patients, only piperacillin-tazobactam contains significant amounts of galactomannan antigen in vitro, that in animals receiving piperacillin-tazobactam circulating galactomannan antigen accumulates in vivo to significantly increased and sustained levels, and that some but not all patients receiving this antibiotic will demonstrate circulating galactomannan above the threshold considered positive for invasive aspergillosis by the recently licensed double sandwich ELISA.

Case Report. Disseminated aspergillosis complicating pregnancy

We report a case of disseminated aspergillosis in a hitherto healthy 24-year-old woman during her 24th week of pregnancy. Relevant findings at autopsy revealed innumerable septate, dichotomously branched (45 degrees ) hyphae compatible with Aspergillus in lung and liver tissues. Cerebral histology showed cerebral vessels occluded by hyphae causing cerebral infarction. There was no evidence of invasive aspergillosis in the placenta and fetal tissues. Aspergillus sp. was confirmed by amplification of a specific 357-base-pair amplicon from a paraffin block containing lung tissue. This case illustrates a previously uncharacterized spectrum of disseminated aspergillosis, indicating the need for a heightened awareness that Aspergillus species are opportunistic agents for invasive and disseminated infection in pregnancy.

Aspergillus antigen testing in bone marrow transplant recipients

Aims—To assess the clinical usefulness of a commercial aspergillus antigen enzyme linked immunosorbent assay (ELISA) in the diagnosis of invasive aspergillosis (IA) in bone marrow transplant recipients, and to compare...

Autopsy-controlled prospective evaluation of serial screening for circulating galactomannan by a sandwich enzyme-linked immunosorbent assay for hematological patients at risk for invasive Aspergillosis.

Efforts to improve the diagnosis of invasive aspergillosis (IA) have been directed towards the detection of fungal antigens, including galactomannan (GM). However, previous evaluations of GM detection have been hampered by a lack of proven cases of IA and by a nonserial study design. This prospective study assessed the diagnostic value of serial screening for circulating GM by using a recently developed sandwich enzyme-linked immunosorbent assay (ELISA) for prolonged-neutropenic and/or steroid-treated patients with hematological disorders. Serum GM levels were monitored twice weekly for 186 consecutive patients at increased risk for IA. The patients were stratified according to the likelihood of IA (proven, probable, possible, and no evidence of IA) by using stringent criteria. Proven IA was defined by characteristic histopathological findings together with a positive culture for Aspergillus species. Autopsy and culture from autopsy specimens was used to verify both positive and negative test results. A total of 2,172 serum samples were tested from 243 episodes (mean, 9 samples/episode). Based on the analysis of 71 patients with confirmed disease status (culture and histology), the sensitivity and specificity of serial GM monitoring were 92.6 and 95.4%, respectively. The positive predictive value was almost 93%, the negative predictive value was 95%, and the efficacy was 94%. False-positive reactions occurred at a rate of nearly 8%, although this figure might have been overestimated. Less than 1% of all tested sera were considered inconclusive. In more than half of the cases, antigenemia was detected before clinical suspicion of IA (median, 6 days before). Serial determination of serum GM by the sandwich ELISA technique is a sensitive tool for the diagnosis of IA in hematological patients at risk. This approach may substantially influence clinical management with regard to preemptive and empirical antifungal therapy.

A polymerase chain reaction enzyme immunoassay for diagnosing infection caused by Aspergillus fumigatus.

AIM: To develop a polymerase chain reaction enzyme immunoassay (PCR-EIA) to measure levels of circulating aspergillus DNA in invasive aspergillosis caused by Aspergillus fumigatus. METHODS: The PCR reaction was based...

Myelopathy resulting from invasive aspergillosis

Aspergillus, a ubiquitous mold, may cause invasive and fatal disease in immunosuppressed patients. Myelopathy is an uncommon presentation of invasive aspergillosis. This report describes three children admitted to the hospital between 1988 and 1995 who developed myelopathy as the first evidence of invasive aspergillosis. All had advanced leukemia and were profoundly immunosuppressed because of chemotherapy and broad-spectrum antibiotics. Weakness and pain presented first; then, sensation to pain and temperature was lost 2 to 6 days later, followed by complete myelopathy. Multiple brain lesions were seen on magnetic resonance imaging in one patient. Despite antifungal therapy, aspergillosis proved fatal within 1 month of onset of myelopathy in all patients. Physicians caring for immunocompromised children should be aware of myelopathy as a presentation of invasive aspergillosis.