Lateral flow assay (LFA) in the diagnosis of COVID-19-associated pulmonary aspergillosis (CAPA): a single-center experience

Abstract

Background Invasive pulmonary aspergillosis (IPA) is seen during coronavirus-2019 (COVID-19), has been reported in different incidences, and is defined as COVID-19-associated pulmonary aspergillosis (CAPA). Detection of galactomannan antigen is an important diagnostic step in diagnosing IPA. Enzyme-linked immunoassay (ELISA) is the most frequently used method, and lateral flow assay (LFA) is increasingly used with high sensitivity and specificity for rapid diagnosis. The present study aimed to compare the sensitivity of LFA and ELISA in the diagnosis of CAPA in COVID-19 patients followed in our hospital's ICU for pandemic (ICU-P). Methods This study included patients with a diagnosis of COVID-19 cases confirmed by polymerase chain reaction and were followed up in ICU-P between August 2021 and February 2022 with acute respiratory failure. The diagnosis of CAPA was based on the European Confederation of Medical Mycology (ECMM) and the International Society for Human and Animal Mycology 2020 (ECMM/ ISHAM) guideline. Galactomannan levels were determined using LFA and ELISA in serum samples taken simultaneously from the patients. Results Out of the 174 patients followed in the ICU-P, 56 did not meet any criteria for CAPA and were excluded from the analysis. The rate of patients diagnosed with proven CAPA was 5.7% (10 patients). A statistically significant result was obtained with LFA for the cut-off value of 0.5 ODI in the diagnosis of CAPA (p < 0.001). The same significant statistical relationship was found for the cut-off value of 1.0 ODI for the ELISA (p < 0.01). The sensitivity of LFA was 80% (95% CI: 0.55–1.05, p < 0.05), specificity 94% (95% CI: 0.89–0.98, p < 0.05); PPV 53% (95% CI: 0.28–0.79, p > 0.05) and NPV was 98% (95% CI: 0.95–1.01, p < 0.05). The risk of death was 1.66 (HR: 1.66, 95% CI: 1.02–2.86, p < 0.05) times higher in patients with an LFA result of ≥ 0.5 ODI than those with < 0.5 (p < 0.05). Conclusions It is reckoned that LFA can be used in future clinical practice, particularly given its effectiveness in patients with hematological malignancies and accuracy in diagnosing CAPA.

Diagnostic accuracy of galactomannan and lateral flow assay in invasive aspergillosis: A diagnostic meta-analysis

“…Among these studies, 20 were duplicates or targeted patients, five were non-human studies, and 10 studies did not report data of interest. Ultimately, 19 articles [ [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] , [41] ] were analyzed following eligibility assessment ( Fig. 1 ).…”

Development of DNA-Based Lateral Flow Assay for Detection of LDLR Gene Mutation for Familial Hypercholesterolemia

“…This shows that the LFA method is sensitive and specific, and it can potentially be used as a diagnostic tool for SNP genotyping, which is associated with disease and has an impact on pharmacogenomics. However, LFA is more useful in diagnosing genetic diseases with homogeneous variants, such as thalassemia disease, and for infectious diseases such as COVID-19 ( 36 ), although a systematic review analysis based on preliminary data and pre-print papers has reported that the performance of the LFA has dropped with regard to the newer SARS-CoV-2 variants, the omicron variant, when compared to previous delta variant due to manufacturer dependent and lower viral loads in asymptomatic individuals ( 37 ). For diseases with heterogeneous variants, several techniques, such as whole exome sequencing and targeted sequencing, could be used to identify the variant and subsequent analysis using LFA for the family member can be done ( 34 , 38 , 39 ).…”

Microbiological Diagnosis of Pulmonary Aspergillus Infections

“…[89][90][91] Several studies have investigated the use of LFTs in CAPA patients on serum and BALF (and TA), which showed good accordance with GM on the same samples. [92][93][94][95] In summary, bronchoscopy-based diagnostics remain the mainstay for diagnosis of VAPA.…”