Serum galactomannan assay for diagnosis of probable invasive Aspergillosis in acute leukemia and hematopoietic stem cell transplantation

Efficacy and safety of combination antifungal therapy in Korean haematological patients with invasive aspergillosis

This randomised, double‐blind, placebo‐controlled trial assessed the efficacy, safety and tolerability of voriconazole+anidulafungin (combination) or voriconazole+placebo (monotherapy) for invasive aspergillosis (IA; NCT00531479). We present a post hoc analysis of Korean and non‐Korean patients with IA (including baseline positive serum galactomannan [GM]). Immunocompromised patients ≥ 16 years with IA were randomised 1:1, combination or monotherapy, for ≥ 2 weeks’ treatment. The primary endpoint was 6‐ and 12‐week all‐cause mortality (Korean modified intent‐to‐treat [mITT] population). Overall, 454 patients enrolled (Koreans: 56 [combination: 28, monotherapy: 28], non‐Koreans: 398 [combination: 200, monotherapy: 198]). The mITT population comprised 40 Koreans (combination: 23; monotherapy: 17) and 237 non‐Koreans (combination: 112; monotherapy: 125). Week 6 treatment difference in mortality rate between combination and monotherapy was −6.4% in non‐Koreans. This reduction was more marked in Koreans (−22.4%). Week 12 difference in all‐cause mortality between combination and monotherapy was −17.7% (Koreans) and −20.2% at Week 6 (Koreans; positive baseline GM). Week 6 mortality (Koreans [mITT]; baseline GM >0.5‐2.0) was 0/13 (combination) and 2/6 (monotherapy). Serious adverse events were numerically higher for combination than monotherapy (Koreans: 57.1%, 46.4%; non‐Koreans: 49.5%, 46.0%). In Koreans, combination therapy was associated with marginally better outcomes than monotherapy and more so than in non‐Koreans.

Emergence of Azole-Resistant Aspergillus fumigatus from Immunocompromised Hosts in India

This prospective study shows that the rate of azole-resistant Aspergillus fumigatus (ARAF) in an immunocompromised Indian patient population with invasive aspergillosis (IA) is low, 6/706 (0.8%). This low rate supports the continued use of voriconazole as the first line of treatment. However, the ARAF isolates from India in this study exhibited three kinds of unreported cyp51A mutations, of which two were at hot spots, G54R and P216L, while one was at codon Y431C.

Serum galactomannan antigen as a prognostic and diagnostic marker for invasive aspergillosis in heterogeneous medicine ICU patient population

Objective

This study was conducted to get a complete clinical and mycological picture of invasive aspergillosis (IA) in respiratory medicine ICU of a tertiary care hospital.

Patients

From the cohort of 235 patients only one had proven IA. Based on AspICU algorithm, 21 had putative IA (8.9%), 12 were colonised (5.1%).

Results

Adjusting the confounding factors, significant risk factors for IA were chronic obstructive pulmonary disease (COPD), temperature of ≥38°C, pneumonia and acute respiratory distress syndrome (ARDS). The best predictor of IA was AspICU algorithm (AUC, 1) followed by serum galactomannan antigen (GM) cut-off (≥1.24) calculated based on AspICU algorithm (AUC, 0.822). For 37% of patients, IA diagnoses was made earlier with serum GM than radiology. There were 70/235 (29.8%) deaths within 30 days of enrolment in the study. Aspergillus culture positivity (34/235, 14.5%) was associated with very high mortality (27/34, 79.4%), (p<0.05). The best predictor of mortality was GM cut-off (≥1.24) calculated based on AspICU algorithm (AUC, 0.835).

Conclusion

This study imparts the focus on relatively underestimated Aspergillus infections prevalent in ICUs. The AspICU algorithm was found to be useful over others for IA diagnosis. The prognostic usefulness of serum GM antigen detection test highlighted overlooking the same may not be rewarding for the outcome of IA suspected ICU subpopulation.

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.

Pulmonary aspergillosis as opportunistic mycoses in a cohort of human immunodeficiency virus-infected patients: Report from a tertiary care hospital in North India

OBJECTIVE

The incidence of pulmonary aspergillosis in human immunodeficiency virus (HIV)-infected persons is rising. This study was designed to determine the prevalence of pulmonary aspergillosis in a cohort of HIV-positive patients (n = 71) presenting with lower respiratory tract infection at a tertiary care medical center in India.

METHODS

Sputum samples were collected, and potassium hydroxide mount, cultural characteristics, and lactophenol cotton blue preparations were employed to aid in the identification of Aspergillus species. In addition, serum galactomannan antigen testing was also performed.

RESULTS

Pulmonary aspergillosis was diagnosed in 7 patients, five of whom showed a positive antigenemia indicating invasive form of disease. The prevalence of pulmonary aspergillosis was highest in individuals 21-40 years of age (13.3%). The gender-wise prevalence of pulmonary aspergillosis was 18.7% and 7.7% in females and males, respectively. The common chest radiographic findings noted in patients with pulmonary aspergillosis included a normal chest radiograph in 3 (42.8%), infiltrates in 2 (28.6%), and pleural effusion in 2 (28.6%). The common Aspergillus species recovered from sputa of these patients were Aspergillus flavus (4; 57.1%); Aspergillus fumigatus (2; 28.6%), and Aspergillus niger (1; 14.3%). A predisposing lung condition in the form of pulmonary tuberculosis was identified in 2; Pneumocystis carinii pneumonia in 2 and a dual tubercular and P. carinii infection in one. The mean CD4 count of these patients was 155.86 ± 119.33 cells/µl (median = 117 cells/µl; range = 18-329 cells/µl).

CONCLUSION

Our findings suggest that Aspergillus species be considered possible etiological agents in HIV-positive patients with pulmonary infection.

Galactomannan detection for invasive aspergillosis in immunocompromised patients

BACKGROUND

Invasive aspergillosis is the most common life-threatening opportunistic invasive mycosis in immunocompromised patients. A test for invasive aspergillosis should neither be too invasive nor too great a burden for the already weakened patient. The serum galactomannan enzyme-linked immunosorbent assay (ELISA) seems to have the potential to meet both requirements.

OBJECTIVES

To obtain summary estimates of the diagnostic accuracy of galactomannan detection in serum for the diagnosis of invasive aspergillosis.

SEARCH METHODS

We searched MEDLINE, EMBASE and Web of Science with both MeSH terms and text words for both aspergillosis and the sandwich ELISA. We checked the reference lists of included studies and review articles for additional studies. We conducted the searches in February 2014.

SELECTION CRITERIA

We included cross-sectional studies, case-control designs and consecutive series of patients assessing the diagnostic accuracy of galactomannan detection for the diagnosis of invasive aspergillosis in patients with neutropenia or patients whose neutrophils are functionally compromised. The reference standard was composed of the criteria given by the European Organization for Research and Treatment of Cancer (EORTC) and the Mycoses Study Group (MSG).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed quality and extracted data. We carried out meta-analysis using the bivariate method. We investigated sources of heterogeneity by adding potential sources of heterogeneity to the model as covariates.

MAIN RESULTS

We included 54 studies in the review (50 in the meta-analyses), containing 5660 patients, of whom 586 had proven or probable invasive aspergillosis. When using an optical density index (ODI) of 0.5 as a cut-off value, the sensitivity of the test was 82% (73% to 90%) and the specificity was 81% (72% to 90%). At a cut-off value of 1.0 ODI, the sensitivity was 72% (65% to 80%) and the specificity was 88% (84% to 92%). At a cut-off value of 1.5 ODI, the sensitivity was 61% (47% to 75%) and the specificity was 93% (89% to 97%). None of the potential sources of heterogeneity had a statistically significant effect on either sensitivity or specificity.

AUTHORS' CONCLUSIONS

If we used the test at a cut-off value of 0.5 ODI in a population of 100 patients with a disease prevalence of 9% (overall median prevalence), two patients who have invasive aspergillosis would be missed (sensitivity 82%, 18% false negatives), and 17 patients would be treated unnecessarily or referred unnecessarily for further testing (specificity 81%, 19% false negatives). If we used the test at a cut-off value of 1.5 in the same population, that would mean that four invasive aspergillosis patients would be missed (sensitivity 61%, 39% false negatives), and six patients would be treated or referred for further testing unnecessarily (specificity 93%, 7% false negatives). These numbers should, however, be interpreted with caution because the results were very heterogeneous.

Evaluation of invasive aspergillosis risk of immunocompromised patients alternatively hospitalized in hematology intensive care unit and at home

Contrary to hospital exposure, little is known about the indoor fungal exposure of hematology patients at home. The aim of our study was to investigate the mold exposure of hematology patients both at home and at hospital to assess their invasive aspergillosis (IA) risk. Fungal exposure was assessed by quantifying opportunistic molds at hospital during hospitalization and in homes of 53 hematology patients. IA was diagnosed in 13 of 53 patients and invasive fungal infection (IFI) in one patient. In hospital, no opportunistic species, or low levels of opportunistic species, were found in 98% of weekly controls. Only 2% of hematology intensive care unit (ICU) controls showed a high level of Aspergillus fumigatus spores in corridor air. Five patients IA were hospitalized during these periods. Seven dwellings of 53 (5/14 dwellings of patients with IA/IFI and 2/39 dwellings of non-IA patients) had a percentage of A. fumigatus and Aspergillus flavus to total mold (significant predictor variable of IA/IFI in our study, general linear model, P-value = 0.02) as high as 15%. Maintaining a 'zero Aspergillus' goal at hospital is essential, and establishing specific and individually opportunistic mold monitoring at home could help to further reduce the IA risk through continuous surveillance.

PRACTICAL IMPLICATIONS

This study emphasizes the fact that preventive measures should not be aimed only at the hospital setting: among patients diagnosed with invasive aspergillosis/invasive fungal infection (IA/IFI), 5 of 14 (36%) were exposed to opportunistic fungal species at home exclusively. Moreover, four of these five patients were living in homes having the highest percentage of Aspergillus fumigatus and Aspergillus flavus (>15%), one of which had 48% of A. fumigatus. Therefore, our work supports the need for a counselor to carry out an environmental survey in patients’ homes.