Galactomannan serves as a surrogate endpoint for outcome of pulmonary invasive aspergillosis in neutropenic hematology patients.

BACKGROUND: A noninvasive, objective, reproducible, and quantitative Aspergillus-specific surrogate marker is needed for a more accurate assessment of the outcome of invasive aspergillosis (IA) in patients with a hematologic disorder. The quantitative serum galactomannan index (GMI) assay seems to fulfill the requirements of surrogacy for outcome evaluation. METHODS: Kappa statistics were used to determine the strength of correlation between GMI outcome and clinical outcome (survival or death), autopsy data, and response outcome of IA in 70 adults with prolonged neutropenia. All patients underwent serial GMI monitoring until discharge or death. RESULTS: The overall correlation between GMI and clinical outcome was good at 6 weeks (kappa=0.5882; 95% confidence interval [95% CI], 0.4023-0.7741) and was excellent at 12 weeks (kappa=0.8857; 95% CI, 0.7766-0.9948). Concordance with autopsy findings was perfect (kappa=1). At 6 weeks, the correlation between GMI and response outcome (favorable or unfavorable) was excellent (kappa=0.7523; 95% CI, 0.5803-0.9243). Survival was significantly better in patients who became GMI-negative (P<.0001). CONCLUSIONS: In neutropenic patients with seropositive IA, serum galactomannan index outcome strongly correlates with survival, autopsy findings, and response outcome. This finding may have implications for patient management and for clinical trial design.

Broad-spectrum antifungal prophylaxis in patients with cancer at high risk for invasive mold infections: counterpoint.

Management of invasive mold infections in patients with prolonged neutropenia and hematopoietic stem cell transplant (HSCT) recipients with graft-versus-host disease (GVHD) has been hampered by the difficulty in diagnosing these infections. Definite diagnosis invariably centers on histologic identification of hyphae in tissue or on culture from a sterile body site. Therefore, most practitioners have relied on prophylaxis and empiric therapy. Currently, emphasis is shifting from routine prophylaxis and empiric therapy to screening of patients with neutropenia at high risk so that clinicians can administer appropriate antifungal therapy early, when it can potentially improve patient outcome. Non-culture-based microbiologic tools are at the forefront of this paradigm shift. Commercially available methods to detect fungal antigens and sophisticated techniques to detect fungal DNA may be used as screening tools during the highest risk period. Together with assessment of clinical signs, cultures, and especially CT scanning, these methods are useful for starting antifungal therapy preemptively. While awaiting further evaluation of these tools during the postengraftment period of allogeneic HSCT, mold-active prophylaxis targeting the subgroup of patients with severe acute or chronic GVHD may be justified. However, some critical issues have not yet been adequately addressed, including the generalizability of study results, impact of mucositis and gastrointestinal GVHD on drug bioavailability, need for therapeutic drug monitoring, impact of prophylaxis on the performance of diagnostic assays, and optimal treatment of breakthrough invasive fungal infections.

Immune reconstitution inflammatory syndrome in cancer patients with pulmonary aspergillosis recovering from neutropenia: Proof of principle, description, and clinical and research implications.

BACKGROUND: Assessing the outcome of patients with invasive pulmonary aspergillosis by using conventional criteria is difficult, particularly when clinical and radiologic worsening coincides with neutrophil recovery. Usually, it is assumed that this deterioration is related to progressive aspergillosis, prompting changes in patient management. However, its temporal relation with neutrophil recovery suggests that it may be caused by an immune reconstitution syndrome (IRIS). Galactomannan is an Aspergillus-specific polysaccharide that is released during aspergillosis and is detected by the serum galactomannan test, which has been approved by the United States Food and Drug Administration for the diagnosis of invasive aspergillosis. In this study, the authors used sequential galactomannan testing to distinguish IRIS responses from progressive aspergillosis. METHODS: From April 2001 to December 2006, patients with hematologic malignancies underwent galactomannan screening during periods when they were at risk. The clinical and laboratory findings from patients who had >or=2 consecutive positive galactomannan assays (optical density, >or=0.5) were reviewed. RESULTS: Nineteen neutropenic patients with aspergillosis developed clinical and radiologic pulmonary deterioration during neutrophil recovery. Deterioration coincided with microbiologic response, as documented by rapid normalization of serum galactomannan, and, in 16 patients, was followed by complete clinical response and survival at 3 months, although there were no changes in antifungal therapy. The 3 patients who died during the first month had no evidence of aspergillosis at autopsy examination. CONCLUSIONS: The authors propose that IRIS was responsible for the current findings and provide a definition for the syndrome. They also recommend serial galactomannan testing to guide aspergillosis management. Declining galactomannan values imply IRIS with an aspergillus response and obviate the need for invasive procedures and alternative antifungal therapies, whereas persistent galactomannan elevation indicates progressive aspergillosis and requires prompt treatment modification.