Invasive pulmonary aspergillosis in neutropenic patients during hospital construction: Before and after chemoprophylaxis and institution of HEPA filters

Abstract

during extensive hospital construction and indoor renovation, a nosocomial outbreak of invasive pulmonary aspergillosis occurred in acute leukemia patients treated in a regular ward that has only natural ventilation. The observed infection rate was 50%. Chemoprophylaxis with intravenous continuous low-dose amphotericin B was then instituted as a preventive measure. During the next 18 months invasive pulmonary aspergillosis developed in 43% of acute leukemia patients. After that period a new hematology ward was opened with an air filtration system through high-efficiency particulate air filtration (HEPA) filters, and a bone marrow transplantation program was started on the hematology service. During the following three years, none of the acute leukemia or bone marrow transplantation patients who were hospitalized exclusively in the hematology ward developed invasive pulmonary aspergillosis, although 29% of acute leukemia patients who were housed in a regular ward, because of shortage of space in the new facility, still contracted invasive pulmonary aspergillosis. Overall, 31 patients were diagnosed with invasive pulmonary aspergillosis during almost five years: 74% of patients recovered from invasive pulmonary aspergillosis, and 42% are long-term survivors; 26% of patients died of resistant leukemia with aspergillosis, but no one died of invasive pulmonary aspergillosis alone. In conclusion, during an on-going construction period, an extremely high incidence rate of invasive pulmonary aspergillosis in acute leukemia patients undergoing intensive chemotherapy was observed. Institution of low-dose intravenous amphotericin B prophylaxis marginally reduced the incidence rate of invasive pulmonary aspergillosis. Keeping patients in a special ward with air filtration through a HEPA system eliminated invasive pulmonary aspergillosis completely. Among patients who developed invasive pulmonary aspergillosis, early diagnosis and treatment are probably the explanation for the favorable outcome. Am. J. Hematol. 66:257-262, 2001.

Assessment of microbiological air quality in hemato-oncology units and its relationship with the occurrence of invasive fungal infections: an integrative review

“…This theme included three studies [17][18][19] demonstrating that HEPA fi lters effectively reduced the fungal concentration in the air, thus possibly preventing cases of invasive fungal infections during restructuring periods. Table 2 presents the main fi ndings of these studies.…”

The utility of intensified environmental surveillance for pathogenic moulds in a stem cell transplantation ward during construction work to monitor the efficacy of HEPA filtration

“…HEPA filters have been shown to reduce the level of fungal spores in the air in several studies. 8,11 However, in some studies, HEPA filtration alone has been insufficient in keeping the air clean during…”

“…[4][5][6] Overall, air filtration, particularly by laminar air flow (LAF) or highefficiency particulate air (HEPA) filters, has been shown to decrease the level of fungal contamination in the air and the incidence of invasive aspergillus infections in immunocompromised patients. 7,8 Construction work inside or adjacent to the hospital can cause aspergillosis outbreaks, particularly if the ventilation system is faulty or if the protective measures around the construction area are not sufficient. [9][10][11][12] In a recent review article, construction work was thought to be the main cause of aspergillosis outbreaks in immunocompromised hosts in almost half of the cases.…”

Polyacrylonitrile microscaffolds assembled from mesh structures of aligned electrospun nanofibers as high-efficiency particulate air filters

“…Notably, fine particles (particulate matter < 2.5 mm aerodynamic diameter, PM2.5, promulgated by the US Environmental Protection Agency) are among the most serious air pollutants and can have major adverse health effects (Peters et al 2001), both acute and chronic, ranging from minor upper respiratory irritation to chronic respiratory and lung cancer, acute respiratory infections in children, and chronic bronchitis in adults, as well as aggravating preexisting heart and lung diseases and asthmatic attacks (Kampa and Castanas 2008). One of the most effective strategies for decreasing the impact of harmful particulates is to use high-efficiency particulate air (HEPA) filters in combination with adequate air ventilation (Oren et al 2001). Aerosol filters, made from conventional micro-fiber fabrics, are designed to efficiently capture small particles from the air.…”