Usefulness of Aspergillus Galactomannan Antigen Testing and the Prediction of an Outbreak during Hospital Reconstruction

Comparison of the Performance of Two Galactomannan Detection Tests: Platelia Aspergillus Ag and Aspergillus Galactomannan Ag Virclia Monotest

The use of nonculture-based biomarkers such as the determination of galactomannan is sought for the diagnosis of invasive aspergillosis. To investigate the comparative yield of two tests for the detection of galactomannan in patients with or without proven or probable invasive aspergillosis. Overall, 327 samples (327 patients) were analyzed in a retrospective/prospective study performed in 3 hospitals in Madrid, comparing the determination results in serum or bronchoalveolar lavage of two techniques for galactomannan detection, namely, Platelia Aspergillus Ag (Bio-Rad) and Aspergillus galactomannan Ag Virclia Monotest (Vircell S.L.), following the manufacturer's instructions. Both techniques can automate the process, but the second technique has the advantage of individual processing and assembly of each sample without the need for the additional expense of single-dose strips in controls. In total, 288 of the 327 tests performed showed concordant results between both techniques. The agreement between both methods was к = 0.722, and the correlation between indices was ρ = 0.718. Only 39 samples showed discordant results. In those 39 cases, there were 15 patients with proven or probable invasive aspergillosis criteria. For the samples with clinical criteria as a reference, the areas under the curve of the receiver operating characteristic (ROC) curve were 0.962 for Platelia and 0.968 for VirClia. The VirClia test has been proven to be an alternative for diagnosis due to its friendlier automated format than that of the usual Platelia routine test. The VirClia test also allows individual action and, therefore, a more immediate clinical response. IMPORTANCE Invasive mycoses are increasingly present in immunosuppressed or hospitalized patients with serious illnesses, leading to high rates of morbidity and mortality. Invasive aspergillosis is an infection caused, in a percentage greater than 50%, by the genus Aspergillus. It is vitally important to make an early diagnosis that leads to the application of antifungals in the initial stage of the infection. Therefore, tools are required to help with the early diagnosis of the infection. This comparative study of two enzyme immunoassays is based on the detection of galactomannan antigen in serum and bronchoalveolar lavage samples. A new design based on chemiluminescence and presented in an automated single-dose format is compared to a conventional ELISA technique marketed for years. The results obtained from the prospective and retrospective study indicate a high correlation and degree of agreement between both techniques, as well as in their diagnostic performance.

ICU ENVIRONMENTAL SURFACES ARE A RESERVOIR OF FUNGI: SPECIES DISTRIBUTION IN NORTHERN ITALY

BACKGROUND

Preventing and reducing nosocomial infections is a public health goal. Concern about healthcare-associated fungal infections has increased in recent years, due to the emergence and spread of new pathogens, increasing antifungal resistance and outbreaks in hospital settings.

AIM

This study investigated the presence of medically-relevant fungal species on environmental surfaces in 12 intensive care units of 8 hospitals in Milan, Italy.

METHODS

Environmental samplings, using contact plates on surfaces near bed stations and medical workstations, were conducted between November 2019 and January 2020. Fungi isolated were identified and some were tested in vitro for antifungal susceptibility.

FINDINGS

A total of 401 environmental samples were collected from 61 bed stations and 17 medical workstations. Positive samples were found in all hospitals except one, with positivity rates ranging from 4% to 24.2%. Filamentous fungi were found mainly on infusion pumps (23.2%) and patient tables (21.2%), whereas yeasts were mainly on computers (25%) and floors (10.9%). Fungi were isolated from 12% of total samples. Filamentous fungi, mainly Aspergillus fumigatus, grew in 70.8% of positive samples, and yeasts in 27.1%, mainly Candida parapsilosis (42.8%) and C. glabrata (28.6%). Fungi were detected both near patients' beds and on surfaces at workstations, indicating potential for environment-to-patient, patient-to-patient and healthcare workers-to-patient transmission CONCLUSIONS: This study highlights that surveillance in hospital settings through environmental sampling may be an important component of fungal infection prevention.

Evaluation of Nosocomial Infection Control Measures to Minimize the Risk of Aspergillus Dispersion During Major Demolition Work: A Case Study of a Japanese University Hospital

OBJECTIVES

To verify the effectiveness of our infection control measures based on the infection control risk assessment (ICRA) to minimize the risk of Aspergillus dispersion before, during, and after demolition work in a university hospital.

BACKGROUND

It is widely accepted that invasive aspergillosis is associated with construction, renovation, and demolition activities within or close to hospital sites. However, the risk is underestimated, and only limited preventive measures are taken in Japanese hospitals.

METHOD

The demolition process, carried out in July 2014, was supervised by our facility management in collaboration with the infection prevention team and followed an adapted ICRA tool. Dust containment measures were implemented to reduce the risk of airborne Aspergillus contamination. Air sampling was performed at four wards in the adjacent hospital buildings to assess the containment measures' effectiveness.

RESULTS

A high, undetermined number of colonies of bacteria and molds were detected on all outside balconies before demolition. During demolition, Aspergillus spp. was detected only in the ward closest to the demolition site. However, no case of aspergillosis was reported. The difference-in-difference analysis revealed that the interaction between the demolition activity, height of the ward, and distance of the air intake to the demolition activities resulted in a significant increase in the numbers of Aspergillus spp.

CONCLUSIONS

When large-scale demolition work occurs in hospital premises, Aspergillus spp. may increase in the ward where the vertical and horizontal distance of air intake from the demolition site is close, even though infection control measures based on the ICRA are implemented.

Biomarkers of fungal infection: Expert opinion on the current situation

The introduction of non-culture-based diagnostic techniques is revolutionizing the world of microbiological diagnosis and infection assessment. Fungi are no exception, and the introduction of biomarkers has opened up enormous expectations for better management of these entities. Biomarkers are diverse, their targets are also diverse and their evaluation has been done preferably in an individualized use and with deficient designs. Less is known about the value of the combined use of biomarkers and the impact of the negativity of two or more biomarkers on antifungal treatment decisions has been poorly studied. Given the paucity of prospective, randomized and definitive studies, we have convened experts from different fields, with an interest in invasive fungal infections, to answer some questions about the current relevant use of fungal biomarkers. This document summarizes the answers of these experts to the different questions.