Invasive Pulmonary Aspergillosis
A 45-year-old man receiving induction chemotherapy for acute myeloid leukemia has been neutropenic for 18 days with persistent fever of 38.9 °C despite 7 days of meropenem and vancomycin. He now has right-sided pleuritic chest pain and small-volume hemoptysis. Computed tomography shows two peripheral nodules with surrounding ground-glass halos. Serum galactomannan index is 1.8 and bronchoalveolar lavage grows Aspergillus fumigatus. What is the most appropriate first-line treatment?
- A.VoriconazoleCorrect
- B.Fluconazole
- C.Anidulafungin
- D.Flucytosine
Explanation
Voriconazole is the first-line agent for invasive pulmonary aspergillosis, and this patient has the classic picture: prolonged profound neutropenia, persistent fever despite broad-spectrum antibacterials, pleuritic pain with hemoptysis from angioinvasion, nodules with a halo sign on CT, a positive galactomannan, and acutely branching septate hyphae. A landmark randomized trial showed voriconazole gave better survival and fewer severe adverse effects than amphotericin B deoxycholate, and isavuconazole is a comparably effective alternative with fewer drug interactions and no need for level monitoring. Triazoles inhibit fungal lanosterol 14-alpha-demethylase and so block ergosterol synthesis; voriconazole is metabolized by cytochrome P450 enzymes, which creates important interactions with many chemotherapeutic and immunosuppressive drugs, and it can cause transient visual disturbance, hepatotoxicity, and QT prolongation, so therapeutic drug monitoring is advised. Liposomal amphotericin B is the main alternative when triazoles cannot be used, and salvage or combination therapy may include an echinocandin. Fluconazole has no meaningful activity against Aspergillus because it covers only yeasts such as Candida albicans and Cryptococcus. Echinocandins such as anidulafungin or caspofungin inhibit beta-1,3-glucan synthesis and are only fungistatic against Aspergillus, so they are salvage or combination agents rather than monotherapy. Flucytosine is used with amphotericin B for cryptococcal meningitis and has no role here. Alongside antifungal therapy, neutrophil recovery is the strongest determinant of outcome.
Why each option
- A.
- Correct. Voriconazole is first-line for invasive aspergillosis and improved survival compared with conventional amphotericin B in randomized data.
- B.
- Fluconazole lacks activity against molds and covers only yeasts such as Candida and Cryptococcus.
- C.
- Echinocandins are only fungistatic against Aspergillus and are used for salvage or combination therapy, not as first-line monotherapy.
- D.
- Flucytosine is combined with amphotericin B for cryptococcal disease and has no role in aspergillosis.
Reference: IDSA Practice Guidelines for the Diagnosis and Management of Aspergillosis, 2016; UpToDate 2025, Treatment and prevention of invasive aspergillosis
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