Refractory invasive pulmonary aspergillosis caused by two Aspergillus species in an allogeneic hematopoietic stem cell transplantation recipient.

Invasive fungal infections are critical complications in patients with hematological malignancies. Herein, we report a case of refractory invasive pulmonary aspergillosis (IPA) caused by two Aspergillus species in a recipient of hematopoietic stem cell transplantation. Repeated sputum cultures revealed causative pathogens, which were identified as Aspergillus terreus and Aspergillus flavus. The antifungal susceptibility testing showed that these Aspergillus species had a high minimal inhibitory concentration against amphotericin B, suggesting that they caused the refractory infection in this patient. Although the patient was treated with a combination of isavuconazole and micafungin, the IPA worsened, and the patient died due to multiple organ failure. The findings from this case highlight the complexity of refractory invasive fungal infections, wherein multiple fungal species can simultaneously affect patients, particularly those with severely compromised immune function. Further investigation is urgently required to improve the management strategies for refractory IPA, including early pathogen identification and novel antifungal agent development.