Information on paracoccidioidomycosis (PCM) in Argentina is fragmented and has historically been based on estimates, supported only by a series of a few reported cases. Considering the lack of global information, a national multicentric study in order to carry out a more comprehensive analysis was warranted. We present a data analysis including demographic and clinical aspects of a historical series of 466 cases recorded over 10 years (2012–2021). Patients were aged from 1 to 89 years. The general male: female (M:F) ratio was 9.5:1 with significant variation according to the age group. Interestingly, the age range 21–30 shows an M:F ratio of 2:1. Most of the cases (86%) were registered in northeast Argentina (NEA), showing hyperendemic areas in Chaco province with more than 2 cases per 10,000 inhabitants. The chronic clinical form occurred in 85.6% of cases and the acute/subacute form occurred in 14.4% of cases, but most of these juvenile type cases occurred in northwestern Argentina (NWA). In NEA, the incidence of the chronic form was 90.6%; in NWA, the acute/subacute form exceeded 37%. Diagnosis by microscopy showed 96% positivity but antibody detection displays 17% of false negatives. Tuberculosis was the most frequent comorbidity, but a diverse spectrum of bacterial, fungal, viral, parasitic, and other non-infectious comorbidities was recorded. This national multicenter registry was launched in order to better understand the current status of PCM in Argentina and shows the two endemic zones with a highly diverse epidemiology.

There are no data available on the effectiveness and safety of isavuconazole (ISA) for treating breakthrough invasive fungal infections (bIFIs). A retrospective and prospective cohort study was conducted between January 2020 and March 2025 in 13 centers in Argentina. Hematologic diseases (HD) and hematopoietic stem cell transplant (HSCT) patients who received ISA for IFI were included and followed for 12 weeks. Patients with proven and probable bIFIs and non-bIFIs were compared. One hundred and sixty-three patients were included. IFIs were classified as proven (13.50%), probable (26.99%) and possible (59.51%). Among 66 proven and probable IFIs, 53.03% were bIFIs, with aspergillosis and mucormycosis being the most common. Twenty-three (34.85%) patients had acute myelogenous leukemia, and 40.91% had received HSCT. Forty-eight (72.73%) patients experienced neutropenia, with a median duration of 26 days (interquartile range [IQR] 16-44). Fluconazole and posaconazole were the antifungal prophylaxis most frequently received. ISA was prescribed as first-line therapy in 31 (46.97%) patients. The other 35 received ISA as a continuation therapy, mainly as a step-down therapy after liposomal amphotericin B. Four (6.06%) patients developed adverse effects, and one discontinued ISA. The 90-day overall clinical response between patients with bIFI vs. non-bIFI was 91.4% vs. 70.9% (p=0.052). The 90-day overall and IFI-related mortality rates were, respectively, 11.4% vs. 32.3% (p = 0.068) and 5.7% vs. 9.7% (p = 0.659). The study data evidence ISA effectiveness and safety for the treatment of HD and HSCT patients with and without bIFIs.

There are no data available on the effectiveness and safety of isavuconazole (ISA) for treating breakthrough invasive fungal infections (bIFIs). A retrospective and prospective cohort study was conducted between January 2020 and March 2025 in 13 centers in Argentina. Hematologic diseases (HD) and hematopoietic cell transplantation (HCT) patients who received ISA for IFI were included and followed for 12 weeks. Patients with proven and probable bIFIs and non-bIFIs were compared. One hundred and sixty-three patients were included. IFIs were classified as proven (13.5%), probable (26.9%) and possible (59.5%). Among 66 proven and probable IFIs, 53% were bIFIs, with aspergillosis and mucormycosis being the most common. Twenty-three (34.8%) patients had acute myelogenous leukemia, and 40.9% had received HCT. Forty-eight (72.7%) patients experienced neutropenia, with a median duration of 26 days (interquartile range [IQR] 16–44). Fluconazole and posaconazole were the most frequently received antifungal prophylaxis. ISA was prescribed as first-line therapy in 31 (46.9%) patients. The other 35 received ISA as a continuation therapy, mainly as a step-down therapy after liposomal amphotericin B. Four (6.1%) patients developed adverse effects, and one discontinued ISA. The 90-day overall clinical response between patients with bIFI vs. non-bIFI was 91.4% vs. 70.9% (p = 0.052). The 90-day overall and IFI-related mortality rates were, respectively, 11.4% vs. 32.3% (p = 0.068) and 5.7% vs. 9.7% (p = 0.659). The study data evidence ISA effectiveness and safety for the treatment of HD and HCT patients with and without bIFIs.