Rapid detection of dermatophytes using the Seegene Novaplex™ dermatophyte assay.

OBJECTIVES: We assessed the performance of the Seegene Novaplex™ Dermatophyte Assay for diagnosis of dermatophytosis. METHODS: Sixty-one clinical samples from skin, nail, hair and culture were selected based on RT-PCR according to Wisselink et al. Of these samples, 26 samples were negative and 35 samples were positive with 39 dermatophytes strains. Emerging fungal strains harbouring terbinafine resistance (i.e. T. indotineae and T. mentagrophytes) were included. RESULTS: The specificities of the Novaplex™ Dermatophyte Assay ranged between 94.3% and 97.9%. The sensitivities for the detection of T. rubrum complex, T. mentagrophytes/T. interdigitale species complex and C. albicans were 94.1% (95% CI: 71.3-99.9), 78.6% (95% CI: 49.2-95.3) and 100% (95% CI: 69.2-100), respectively, with Cohen's kappa of at least 72.9%. CONCLUSIONS: The Seegene Novaplex™ Dermatophyte Assay can be used for reliable screening of dermatophytes, including emerging strains in a routine laboratory setting.

[Persistent dermatomycosis due toTrichophyton indotineae]. / Hardnekkige dermatomycose doorTrichophyton indotineae.

Trichophyton indotineae is a recently identified dermatophyte that frequently causes extensive and persistent dermatomycosis, particularly tinea corporis, tinea cruris, and tinea faciei. The infection is frequently encountered in countries of the Indian subcontinent and surrounding areas. In Europe, T. indotineae has mainly been detected in patients with an epidemiological link to the aforementioned regions. Unlike dermatomycoses caused by other dermatophyte species, infections caused by T. indotineae often exhibit treatment failure with commonly prescribed antifungal drugs. Reduced susceptibility to terbinafine is often observed in T. indotineae. In addition, reduced susceptibility to itraconazole has also been reported. Due to the extensive and persistent nature of the infection, as well as the reduced susceptibility to antifungal drugs, international experts recommend aggressive treatment of T. indotineae using a combination of oral and topical antifungals. Susceptibility testing may be warranted to guide treatment decisions. Early recognition of T. indotineae infections is crucial to prevent prolonged recurrences.

Diagnostic performances of four commercially available assays for the identification of SARS-CoV-2, influenza type A/B virus and RSV.

We evaluated the diagnostic performance of 4 commercially NAAT for detecting SARS-CoV-2 RNA, Influenza type A/B virus and RSV. Included tests were the Allplex™ SARS-CoV-2 fast PCR Assay (RNA extraction-free), Allplex™ RV Master Assay, Allplex™ SARS-CoV-2 fast MDx Assay (LAMP) and Aptima™ SARS-CoV-2/Flu Assay (RT-TMA). The assays' performance characteristics were determined using nasopharyngeal swabs from 270 patients with suspected SARS-CoV-2 infection. A total of 215 SARS-CoV-2 positive, 55 negative nasopharyngeal swabs and 19 bacteria strains were included. The sensitivities and specificities for detecting SARS-CoV-2, Influenza type A virus and RSV ranged between 81.8% and 100% with extremely good agreements (κ ≥ 86.8 %). The Aptima™ SARS-CoV-2/Flu Assay introduced a new result parameter, that is, TTime. Here, we showed that TTime may be used as a surrogate for Ct-value. We concluded that all assays assessed in this study can be used for routine detection of SARS-CoV-2, Influenza type A virus and RSV.

Factors Associated with Worse Lung Function in Cystic Fibrosis Patients with Persistent Staphylococcus aureus.

BACKGROUND: Staphylococcus aureus is an important pathogen in cystic fibrosis (CF). However, it is not clear which factors are associated with worse lung function in patients with persistent S. aureus airway cultures. Our main hypothesis was that patients with high S. aureus density in their respiratory specimens would more likely experience worsening of their lung disease than patients with low bacterial loads. METHODS: Therefore, we conducted an observational prospective longitudinal multi-center study and assessed the association between lung function and S. aureus bacterial density in respiratory samples, co-infection with other CF-pathogens, nasal S. aureus carriage, clinical status, antibiotic therapy, IL-6- and IgG-levels against S. aureus virulence factors. RESULTS: 195 patients from 17 centers were followed; each patient had an average of 7 visits. Data were analyzed using descriptive statistics and generalized linear mixed models. Our main hypothesis was only supported for patients providing throat specimens indicating that patients with higher density experienced a steeper lung function decline (p<0.001). Patients with exacerbations (n = 60), S. aureus small-colony variants (SCVs, n = 84) and co-infection with Stenotrophomonas maltophilia (n = 44) had worse lung function (p = 0.0068; p = 0.0011; p = 0.0103). Patients with SCVs were older (p = 0.0066) and more often treated with trimethoprim/sulfamethoxazole (p = 0.0078). IL-6 levels positively correlated with decreased lung function (p<0.001), S. aureus density in sputa (p = 0.0016), SCVs (p = 0.0209), exacerbations (p = 0.0041) and co-infections with S. maltophilia (p = 0.0195) or A. fumigatus (p = 0.0496). CONCLUSIONS: In CF-patients with chronic S. aureus cultures, independent risk factors for worse lung function are high bacterial density in throat cultures, exacerbations, elevated IL-6 levels, presence of S. aureus SCVs and co-infection with S. maltophilia. TRIAL REGISTRATION: ClinicalTrials.gov NCT00669760.