Aspergillosis
Invasive aspergillosis is an angioinvasive mold infection of neutropenic and immunosuppressed hosts that begins in the respiratory tract and disseminates hematogenously, diagnosed with CT, galactomannan, and biopsy, and treated first-line with voriconazole.
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What this article covers
- Overview
Angioinvasive mold infection: Aspergillus fumigatus is the most common species causing human disease, followed by A.
- Epidemiology
Most common invasive mold infection in patients with prolonged neutropenia and hematopoietic stem cell transplant (HSCT) recipients; pulmonary aspergillosis is also the most common invasive mold…
- Risk factors
Neutropenia, particularly profound and prolonged neutropenia after cytotoxic chemotherapy, is the dominant risk factor for invasive disease.
- Pathophysiology
Inhalation of conidia (spores) deposits Aspergillus in the airway and alveoli; the outcome depends entirely on host immune competence.
- Clinical features
Fever refractory to broad-spectrum antibiotics in a neutropenic host is frequently the only presenting feature of invasive aspergillosis and should prompt evaluation.
- Differential diagnosis
Bacterial pneumonia (including nosocomial and Pseudomonas pneumonia): overlapping fever and infiltrates in an immunosuppressed host, distinguished by positive bacterial cultures and lack of the halo/air-crescent sign.
- Diagnosis
Definitive diagnosis of invasive aspergillosis requires tissue biopsy demonstrating septate, acute-angle (dichotomously) branching hyphae with invasion, but because biopsy is frequently not feasible…
- Management
First, start voriconazole as first-line therapy for invasive or chronic necrotizing pulmonary aspergillosis: 6 mg/kg IV every 12 hr for two loading doses, then 4 mg/kg IV every 12 hr, transitioning…
- Complications
Hematogenous dissemination to the brain (abscess, infarction), skin (hemorrhagic lesions from septic emboli), and other organs, reflecting the angioinvasive nature of the infection.
- Prognosis
Mortality is high in invasive aspergillosis, particularly when neutropenia or immunosuppression cannot be reversed; timely diagnosis and treatment are essential to decrease morbidity and mortality…
- Prevention
Mold-active azole prophylaxis (posaconazole, voriconazole, or isavuconazole) during periods of anticipated prolonged neutropenia (e.g., acute myeloid leukemia induction chemotherapy, HSCT conditioning) reduces invasive mold disease.
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