Invasive pulmonary infection due to Thermoascus crustaceus in a kidney transplant recipient Mihai Mareș,1,* Valentina-Ruxandra Moroti-Constantinescu,2,3,* Luminița Voroneanu,4,5 Florica Doroftei,6 Adrian Covic,4,5 Ovidiu-Alexandru Mederle71Laboratory of Antimicrobial Chemotherapy, Ion Ionescu de la Brad University, Iași, Romania; 24th Department, “Matei Balș” National Institute of Infectious Diseases, Bucharest, Romania; 3Department of Infectious Diseases, “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania; 4Department of Nephrology, “Gr. T. Popa” University of Medicine and Pharmacy, Iași, Romania; 5Renal Transplantation Center, “C. I. Parhon” Clinical Hospital, Iași, Romania; 6Intelcentru, “Petru Poni” Institute of Macromolecular Chemistry, Iași, Romania; 7Department of Microscopic Morphology/Histology, Angiogenesis Research Center, “Victor Babeș” University of Medicine and Pharmacy, Timișoara, Romania*These authors contributed equally to this workAbstract: The first case of invasive pulmonary infection due to the thermophilic fungus Thermoascus crustaceus in a kidney transplant recipient is described. For the identification of the fungal isolate, morphological aspects and molecular analysis have been used. The case report emphasizes this fungal species as an opportunistic human pathogen and underlines the importance of an accurate laboratory diagnosis for the correct management of the patient.Keywords: Thermoascus crustaceus, thermophilic fungi, pulmonary infection, caspofungin, immunosuppression