The indoor air as a potential determinant of the frequency of invasive aspergillosis in the intensive care

Prevalence of airborne fungi in Brazil and correlations with respiratory diseases and fungal infections

Airborne fungi are dispersed through the air. The aim of this study was to determine the prevalence of airborne fungi in Brazil and understand the relationship between fungal growth and respiratory diseases and infections. We conducted an integrative literature review of studies conducted in Brazil based on searches of the PubMed, MEDLINE-BIREME, SciELO, and LILACS databases for full-text articles published between 2000 and 2022. The searches returned 147 studies, of which only 25 met the inclusion criteria. The most prevalent genera of airborne fungi in Brazil are Aspergillus, Penicillium, Cladosporium, Curvularia, and Fusarium. The studies were conducted in the states of Maranhão, Ceará, Piauí, Sergipe, Mato Grosso, Pernambuco, Rio Grande do Sul, Santa Catarina, Rio de Janeiro, São Paulo, and Minas Gerais. The findings also show the relationship between fungi and meteorological factors and seasonality, the sensitivity of atopic individuals to fungi, and the main nosocomial mycoses reported in the literature. This work demonstrates the importance of maintaining good microbiological air quality to prevent potential airborne diseases.

Fungi in the indoor air of critical hospital areas: a review

Invasive fungal infection is an important cause of mortality and morbidity in neonates, especially in low-birthweight neonates. The contribution of fungi in the indoor air to the incidence of mucocutaneous colonization and to the risk of invasive fungal infection in this population is uncertain. This review aimed to identify and to summarize the best available evidence on the fungal contamination in the indoor air of critical hospital areas with an emphasis on pediatric/neonatal ICUs. Publications from 2005 to 2019 were searched in the databases Scientific Electronic Library Online (SciELO), US National Library of Medicine National Institutes of Health Search (PubMed), and Latin American Caribbean Health Sciences (LILACS). Descriptors in Health Sciences (DeCS) were used. Research papers published in Portuguese, English, and Spanish were included. Twenty-nine papers on all continents except Australia were selected. The results showed that the air mycobiota contained several fungal species, notably Aspergillus, Penicillium, Cladosporium, Fusarium, and yeast (Candida) species. The selected papers point out the risks that fungi pose to neonates, who have immature immune system, and describe simultaneous external factors (air humidity, seasonality, air and people flow, use of particulate filters, and health professionals' hand hygiene) that contribute to indoor air contamination with fungi. Improving communication among health professionals is a great concern because this can prevent major health complications in neonates, especially in low-birthweight neonates. The results reinforced the need to monitor environmental fungi more frequently and efficiently in hospitals, especially in neonatal ICUs.

A polymicrobial fungal outbreak in a regional burn center after Hurricane Sandy

OBJECTIVE

To describe a polymicrobial fungal outbreak after Hurricane Sandy.

DESIGN

An observational concurrent outbreak investigation and retrospective descriptive review.

SETTING

A regional burn intensive care unit that serves the greater Baltimore area, admitting 350-450 burn patients annually.

PATIENTS

Patients with burn injuries and significant dermatologic diseases such as toxic epidermal necrolysis who were admitted to the burn intensive care unit.

METHODS

An outbreak investigation and a retrospective review of all patients with non-candida fungal isolates from 2009-2016 were performed.

RESULTS

A polymicrobial fungal outbreak in burn patients was temporally associated with Hurricane Sandy and associated with air and water permeations in the hospital facility. The outbreak abated after changes to facility design.

CONCLUSIONS

Our results suggest a possible association between severe weather events like hurricanes and nosocomial fungal outbreaks. This report adds to the emerging literature on the effect of severe weather on healthcare-associated infections.

Aspergillus prevalence in air conditioning filters from vehicles: Taxis for patient transportation, forklifts, and personal vehicles

The frequency and importance of Aspergillus infections is increasing worldwide. This study aimed to assess the occupational exposure of forklifts and taxi drivers to Aspergillus spp. Nineteen filters from air conditioning system of taxis, 17 from forklifts and 37 from personal vehicles were assessed. Filters extract were streaked onto MEA, DG18 and in azole-supplemented media. Real-time quantitative PCR amplification of selected Aspergillus species-complex was also performed. Forklifts filter samples presented higher median values. Aspergillus section Nigri was the most observed in forklifts filters in MEA (28.2%) and in azole-supplemented media. DNA from Aspergillus sections Fumigati and Versicolores was successfully amplified by qPCR. This study enlightens the added value of using filters from the air conditioning system to assess Aspergillus spp. occupational exposure. Aspergillus azole resistance screening should be included in future occupational exposure assessments.

Intensive care medicine research agenda on invasive fungal infection in critically ill patients

PURPOSE

To describe concisely the current standards of care, major recent advances, common beliefs that have been contradicted by recent trials, areas of uncertainty, and clinical studies that need to be performed over the next decade and their expected outcomes with regard to Candida and Aspergillus infections in non-neutropenic patients in the ICU setting.

METHODS

A systematic review of the medical literature taking account of national and international guidelines and expert opinion.

RESULTS

Severe invasive fungal infections (IFIs) are becoming increasingly frequent in critically ill patients. Approximately 80% of IFIs are due to Candida spp. and 0.3-19% to Aspergillus spp. Recent observations emphasize the necessity of building a worldwide sentinel network to monitor the emergence of new fungal species and changes in susceptibility. Robust data on the attributable mortality are essential for the design of clinical studies with mortality endpoints. Although early antifungal therapy for Candida has been recommended in patients with risk factors, sepsis of unknown cause, and positive Candida serum biomarkers [β-1 → 3-D-glucan (BDG) and Candida albicans germ tube antibody (CAGTA)], its usefulness and influence on outcome need to be confirmed. Future studies may specifically address the optimal diagnostic and therapeutic strategies for patients with abdominal candidiasis. Better knowledge of the pharmacokinetics of antifungal molecules and tissue penetration is a key issue for intensivists. Regarding invasive aspergillosis, further investigation is needed to determine its incidence in the ICU, its relationship with influenza outbreaks, the clinical impact of rapid diagnosis, and the significance of combination treatment.

CONCLUSIONS

Fundamental questions regarding IFI have to be addressed over the next decade. The clinical studies described in this research agenda should provide a template and set priorities for the clinical investigations that need to be performed.

Evaluation of invasive aspergillosis risk of immunocompromised patients alternatively hospitalized in hematology intensive care unit and at home

Contrary to hospital exposure, little is known about the indoor fungal exposure of hematology patients at home. The aim of our study was to investigate the mold exposure of hematology patients both at home and at hospital to assess their invasive aspergillosis (IA) risk. Fungal exposure was assessed by quantifying opportunistic molds at hospital during hospitalization and in homes of 53 hematology patients. IA was diagnosed in 13 of 53 patients and invasive fungal infection (IFI) in one patient. In hospital, no opportunistic species, or low levels of opportunistic species, were found in 98% of weekly controls. Only 2% of hematology intensive care unit (ICU) controls showed a high level of Aspergillus fumigatus spores in corridor air. Five patients IA were hospitalized during these periods. Seven dwellings of 53 (5/14 dwellings of patients with IA/IFI and 2/39 dwellings of non-IA patients) had a percentage of A. fumigatus and Aspergillus flavus to total mold (significant predictor variable of IA/IFI in our study, general linear model, P-value = 0.02) as high as 15%. Maintaining a 'zero Aspergillus' goal at hospital is essential, and establishing specific and individually opportunistic mold monitoring at home could help to further reduce the IA risk through continuous surveillance.

PRACTICAL IMPLICATIONS

This study emphasizes the fact that preventive measures should not be aimed only at the hospital setting: among patients diagnosed with invasive aspergillosis/invasive fungal infection (IA/IFI), 5 of 14 (36%) were exposed to opportunistic fungal species at home exclusively. Moreover, four of these five patients were living in homes having the highest percentage of Aspergillus fumigatus and Aspergillus flavus (>15%), one of which had 48% of A. fumigatus. Therefore, our work supports the need for a counselor to carry out an environmental survey in patients’ homes.

Current and future therapies for invasive aspergillosis

Invasive fungal infections have increase worldwide and represent a threat for immunocompromised patients including HIV-infected, recipients of solid organ and stem cell transplants, and patients receiving immunosuppressive therapies. High mortality rates and difficulties in early diagnosis characterize pulmonary fungal infections. Invasive pulmonary aspergillosis has been reviewed focussing on therapeutic management. Although new compounds have become available in the past years (i.e., amphotericin B lipid formulations, last-generation azoles, and echinocandines), new diagnostic tools and careful therapeutic management are mandatory to assure an early appropriate targeted treatment that represents the key factor for a successful conservative approach in respiratory fungal infections.