Invasive Aspergillosis
Angioinvasive pulmonary infection caused by *Aspergillus* spp., classically in prolonged neutropenia and transplant recipients. Voriconazole is first-line therapy; diagnosis integrates imaging, galactomannan, and culture.
Key Facts
Key points
- Risk: prolonged neutropenia, allogeneic stem cell transplant, high-dose steroids, advanced HIV.
- Imaging: CT chest may show halo sign early; cavitation later.
- First-line: voriconazole 6 mg/kg IV 12-hourly for 2 doses, then 4 mg/kg 12-hourly (adjust oral dosing per weight); TDM recommended.
- Alternatives: liposomal amphotericin B 3 mg/kg OD IV; isavuconazole loading then maintenance — specialist choice.
- Surgical resection for single lesions/refractory haemoptysis in selected cases.
- Galactomannan in BAL/serum supportive; not fully specific.
Overview
Species
A. fumigatus common; azole-resistant isolates increasingly reported — send cultures.
Forms
Invasive pulmonary, sinus, CNS, cutaneous (direct inoculation).
Clinical Presentation
Symptoms
Fever unresponsive to antibacterials, pleuritic pain, haemoptysis, sinus symptoms.
Examination
Focal lung signs; immunosuppression may blunt classic features.
Differential Diagnosis
| Mimic | Notes |
|---|---|
| Mucormycosis | Ribbon necrosis on imaging; urgent ENT review |
| TB | Acid-fast bacilli, epidemiology |
| Bacterial pneumonia | Microbiology pattern |
Diagnosis / Investigation
Labs
Galactomannan (serum/BAL), (1→3)-β-D-glucan (broad), Aspergillus PCR where available.
Imaging
High-resolution CT chest; consider brain MRI if neurological signs.
Management
Primary therapy
- Voriconazole as above; maintain trough 1–5.5 mg/L (local lab ranges vary).
Salvage
- Liposomal amphotericin or isavuconazole; consider caspofungin combination in refractory cases — ID MDT.
Immune recovery
Reduce immunosuppression where possible; G-CSF for neutropenia.
Prognosis
Mortality high in allogeneic transplant and prolonged neutropenia; early voriconazole improves outcomes.
Other Relevant Information
Drug interactions
Voriconazole is a CYP3A4 substrate/inhibitor — many contraindications (e.g. sirolimus).