Invasive Fungal Infections in Allogeneic Hematopoietic Stem Cell Transplant (Tcth) Recipients Under Antifungal Prophylaxis With Echinocandin: Brazilian Experience

Onco-hematologic patients undergoing TCTH are at high risk for invasive fungal infections (IFI), one of the main causes of morbidity and mortality in this population. Micafungin has been widely used as antifungal prophylaxis due to its safety profile, efficacy, and fewer drug–drug interactions. However, this prophylactic option is concerning because of its low concentration in the gastrointestinal mucosa, with reports of “breakthrough” IFI that remain a clinical challenge. To describe the incidence of IFI in allogeneic TCTH recipients receiving micafungin and to compare it with the group that used other antifungal agents for prophylaxis; to characterize breakthrough fungal infections. Retrospective, observational cohort of all patients who underwent allogeneic TCTH at a private Brazilian hospital between 2011 and 2020, characterizing demographic and clinical data and antifungal used. Clinical, microbiological, therapeutic, and outcome data were collected from electronic records with ethics committee approval. During the study period, 244 allogeneic TCTH procedures were performed; 221 were included in the analysis. All patients received antifungal therapy during neutropenia. The median age was 40 years, and the main donor type was unrelated (41%), followed by fully matched related donor (30%). Micafungin was used in 61% of patients, with a breakthrough IFI incidence of 13.3%, whereas in the group using other antifungals the breakthrough IFI incidence was 19.7%. Candidemia was the main IFI, exclusively by non-albicans species (6 episodes in the “micafungin” group vs 2 in the comparator). Thirty-day mortality was lower in the micafungin group (2.22% vs 5.81%). There was no statistically significant difference in survival between patients receiving different prophylactic regimens, but there was a trend toward worse outcomes among those who used posaconazole compared with micafungin (p = 0.07). Patients on micafungin prophylaxis had a lower need for empirical change to other antifungal classes. Despite the limitations of the study, in this cohort micafungin prophylaxis was associated with a lower incidence of breakthrough IFI and a trend toward better survival. This finding warrants further investigation and may represent an effective prophylactic strategy in high-risk patients such as allogeneic transplant recipients.