Citation: Veríssimo, C.; Toscano, C.; Ferreira, T.; Abreu, G.; Simões, H.; Diogo, J.; Carvalho, D.; Santiago, F.; Lima, A.; Queirós, A.M.; et al. Invasive and Subcutaneous Infections Caused by Filamentous Fungi: Report from a Portuguese Multicentric Surveillance Program. Microorganisms 2022, 10, 1010. https://doi.org/10.3390/ microorganisms10051010 Academic Editor: Elisabetta Blasi Received: 24 March 2022 Accepted: 9 May 2022 Published: 11 May 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). microorganisms Article Invasive and Subcutaneous Infections Caused by Filamentous Fungi: Report from a Portuguese Multicentric Surveillance Program Cristina Veríssimo 1, *, Cristina Toscano 2 , Teresa Ferreira 3 , Gabriela Abreu 4 , Helena Simões 1 , José Diogo 5 , Dinah Carvalho 6 , Felicidade Santiago 7 , Ana Lima 8 , Ana Maria Queirós 9 and Raquel Sabino 1,10 1 Reference Unit for Parasitic and Fungal Infections, Department of Infectious Diseases, National Institute of Health, Dr. Ricardo Jorge, 1649-016 Lisbon, Portugal; helena.simoes@insa.min-saude.pt (H.S.); raquel.sabino@insa.min-saude.pt (R.S.) 2 Microbiology Laboratory, Hospital Egas Moniz, Centro Hospitalar Lisboa Ocidental, 1349-019 Lisbon, Portugal; ctoscano@chlo.min-saude.pt 3 Centro Hospitalar Lisboa Central, 1349-019 Lisbon, Portugal; teresa.ferreira@gmail.com 4 Centro Hospitalar Vila Nova de Gaia/Espinho, EPE, 4434-502 Vila Nova de Gaia, Portugal; mgabiabreu@gmail.com 5 Microbiology Laboratory, Hospital Garcia de Orta, 2805-267 Almada, Portugal; jmcdiogo1@gmail.com 6 Microbiology Laboratory, Centro Hospitalar Lisboa Norte, 1649-035 Lisbon, Portugal; dinahjcarvalho@gmail.com 7 Centro Hospitalar de Leiria, 2410-197 Leiria, Portugal; felicidadesantiago@hotmail.com 8 Microbiology Laboratory, Centro Hospitalar de entre Douro e Vouga, 4520-211 Santa Maria da Feira, Portugal; ana.lima@chedv.min-saude.pt 9 Microbiology Laboratory, Centro Hospitalar Tondela Viseu, 3460-525 Viseu, Portugal; anabentoqueiros@hotmail.com 10 Instituto de Saúde Ambiental, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal * Correspondence: cristina.verissimo@insa.min-saude.pt; Tel.: +351-217-519-247 Abstract: Invasive fungal infections (IFI) have significantly increased over the past years due to advances in medical care for the at-risk immunocompromised population. IFI are often difficult to diagnose and manage, and can be associated with substantial morbidity and mortality. This study aims to contribute to understanding the etiology of invasive and subcutaneous fungal infections, their associated risk factors, and to perceive the outcome of patients who developed invasive disease, raising awareness of these infections at a local level but also in a global context. A laboratory surveillance approach was conducted over a seven-year period and included: (i) cases of invasive and subcutaneous fungal infections caused by filamentous/dimorphic fungi, confirmed by either microscopy or positive culture from sterile samples, (ii) cases diagnosed as probable IFI according to the criteria established by EORTC/MSG when duly substantiated. Fourteen Portuguese laboratories were enrolled. Cases included in this study were classified according to the new consensus definitions of invasive fungal diseases (IFD) published in 2020 as follows: proven IFI (N = 31), subcutaneous fungal infection (N = 23). Those proven deep fungal infections (N = 54) totalized 71.1% of the total cases, whereas 28.9% were classified as probable IFI (N = 22). It was possible to identify the etiological fungal agent in 73 cases (96%). Aspergillus was the most frequent genera detected, but endemic dimorphic fungi represented 14.47% (N = 11) of the total cases. Despite the small number of cases, a high diversity of species were involved in deep fungal infections. This fact has implications for clinical and laboratory diagnosis, and on the therapeutic management of these infections, since different species, even within the same genus, can present diverse patterns of susceptibility to antifungals. Keywords: invasive fungal infections; subcutaneous fungal infections; fungal epidemiology; surveillance Microorganisms 2022, 10, 1010. https://doi.org/10.3390/microorganisms10051010 https://www.mdpi.com/journal/microorganisms