Juan Carlos García-Ruiz1, Iñigo Olazábal1, Rosa María Adán Pedroso2, Leyre López-Soria3, Verónica Velasco-Benito4, José Antonio Sánchez-Aparicio5, Aurora Navajas2, Miguel Montejo6, María-Dolores Moragues7. 1. Servicio de Hematología y Hemoterapia, BioCruces Health Research Institute, Hospital Universitario Cruces, Plaza de Cruces s/n, 48903 Barakaldo, Bizkaia, Spain. 2. Servicio de Pediatría, BioCruces Health Research Institute, Hospital Universitario Cruces, Barakaldo, Bizkaia, Spain. 3. Servicio de Microbiología, Hospital Universitario Cruces, Barakaldo, Bizkaia, Spain. 4. Servicio de Anatomía Patológica, BioCruces Health Research Institute, Hospital Universitario Cruces, Barakaldo, Bizkaia, Spain. 5. Servicio de Oftalmología, Hospital Universitario Cruces, Barakaldo, Bizkaia, Spain. 6. Unidad de Enfermedades Infecciosas, Hospital Universitario Cruces, BioCruces Health Research Institute, Universidad del País Vasco (UPV/EHU), Barakaldo, Bizkaia, Spain. 7. Departamento de Enfermería, Escuela de Enfermería, Universidad del País Vasco UPV/EHU, Leioa, Bizkaia, Spain. Electronic address: lola.moragues@ehu.es.
Abstract
BACKGROUND: Fungi of the genus Fusarium are primarily plant pathogens and saprobes that produce disseminated infections in immunologically deficient humans. After aspergillosis, disseminated fusariosis is the second most common cause of invasive infection by filamentous fungi in patients with hematologic malignancies or those undergoing transplants of hematopoietic progenitors. AIMS: Disseminated fusariosis (DF) is considered an extremely rare infection and has reached a stable incidence rate, but its high mortality rate and the lack of an optimal management protocol have raised increasing interest in this mycosis. METHODS: We present three cases of DF produced by Fusarium oxysporum species complex, Fusarium solani species complex and the highly unusual Fusarium dimerum in patients with advanced hematological malignancies diagnosed in our hospital between 2007 and 2011. The species level identification of the Fusarium isolates was established by sequencing their TEF1 gene. RESULTS: The isolates showed low susceptibility to most of the antifungal agents analyzed, except that observed for F. dimerum to amphotericin B (AmB) and terbinafine, and F. oxysporum species complex to AmB. Interestingly, the strain of F. solani species complex exhibited high MIC values for AmB and voriconazole, notwithstanding these drugs were used for treatment with good results. Other relevant aspects to be considered in the treatment of DF are surgically cleaning foci of infection, withdrawing presumably contaminated catheters and recovery from neutropenia. CONCLUSIONS: The prevention of infection in colonized patients, the maintenance of a high level of diagnostic suspicion for early diagnosis, and the combined, vigorous and prolonged use of L-AmB and voriconazole are essential to decrease the mortality rate of this devastating infection.
BACKGROUND: Fungi of the genus Fusarium are primarily plant pathogens and saprobes that produce disseminated infections in immunologically deficient humans. After aspergillosis, disseminated fusariosis is the second most common cause of invasive infection by filamentous fungi in patients with hematologic malignancies or those undergoing transplants of hematopoietic progenitors. AIMS: Disseminated fusariosis (DF) is considered an extremely rare infection and has reached a stable incidence rate, but its high mortality rate and the lack of an optimal management protocol have raised increasing interest in this mycosis. METHODS: We present three cases of DF produced by Fusarium oxysporum species complex, Fusarium solani species complex and the highly unusual Fusarium dimerum in patients with advanced hematological malignancies diagnosed in our hospital between 2007 and 2011. The species level identification of the Fusarium isolates was established by sequencing their TEF1 gene. RESULTS: The isolates showed low susceptibility to most of the antifungal agents analyzed, except that observed for F. dimerum to amphotericin B (AmB) and terbinafine, and F. oxysporum species complex to AmB. Interestingly, the strain of F. solani species complex exhibited high MIC values for AmB and voriconazole, notwithstanding these drugs were used for treatment with good results. Other relevant aspects to be considered in the treatment of DF are surgically cleaning foci of infection, withdrawing presumably contaminated catheters and recovery from neutropenia. CONCLUSIONS: The prevention of infection in colonized patients, the maintenance of a high level of diagnostic suspicion for early diagnosis, and the combined, vigorous and prolonged use of L-AmB and voriconazole are essential to decrease the mortality rate of this devastating infection.