RESUMO
We evaluated the analytical and workflow characteristics of the ARIES Clostridium difficile assay, a recently developed qPCR-based test for toxigenic C. difficile ARIES was compared to the illumigene C. difficile assay, a commonly employed, loop-mediated amplification technique with similar sample-to-result capabilities. Following illumigene analysis, 122 positive and 164 negative stool specimens were banked for subsequent ARIES testing. The analytical agreement between the platforms was high: 93.4% positive agreement (89.0-97.8%) and 97.5% negative agreement (95.2-99.9%). For discordant specimens, amplification/bidirectional sequencing of tcdA/tcdB demonstrated toxigenic C. difficile in 2/4 illumigene(-)ARIES(+) and 2/8 illumigene(+)ARIES(-) specimens. In a time-motion study, the ARIES assay required less hands-on time than illumigene, but with greater total testing time. Overall, these findings support the ARIES C. difficile Assay as a new option for laboratories in their diagnostic repertoire.
Assuntos
Bioensaio/métodos , Clostridioides difficile/genética , Fluxo de Trabalho , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/microbiologia , Fezes/microbiologia , HumanosRESUMO
PURPOSE: BRAF-inhibition (BRAFi) therapy for advanced melanoma carries a high rate of secondary cutaneous squamous cell carcinoma (cSCC) and risk of other cancers. UV radiation and α-genus human papillomavirus (HPV) are highly associated with SCC, but a novel role for ß-genus HPV is suspected in BRAFi-cSCC. Cutaneous ß-HPV may act in concert with host and environmental factors in BRAFi-cSCC. EXPERIMENTAL DESIGN: Primary BRAFi-cSCC tissue DNA isolated from patients receiving vemurafenib or dabrafenib from two cancer centers was analyzed for the presence of cutaneous oncogenic viruses and host genetic mutations. Diagnostic specimens underwent consensus dermatopathology review. Clinical parameters for UV exposure and disease course were statistically analyzed in conjunction with histopathology. RESULTS: Twenty-nine patients contributed 69 BRAFi-cSCC lesions. BRAFi-cSCC had wart-like features (BRAFi-cSCC-WF) in 22% of specimens. During vemurafenib therapy, BRAFi-cSCC-WF arose 11.6 weeks more rapidly than conventional cSCC when controlled for gender and UV exposure (P value = 0.03). Among all BRAFi-cSCC, ß-genus HPV-17, HPV-38, HPV-111 were most frequently isolated, and novel ß-HPV genotypes were discovered (CTR, CRT-11, CRT-22). Sequencing revealed 63% of evaluated BRAFi-cSCCs harbored RAS mutations with PIK3CA, CKIT, ALK, and EGFR mutations also detected. CONCLUSIONS: We examined clinical, histopathologic, viral, and genetic parameters in BRAFi-cSCC demonstrating rapid onset; wart-like histomorphology; ß-HPV-17, HPV-38, and HPV-111 infection; UV damage; and novel ALK and CKIT mutations. Discovered ß-HPV genotypes expand the spectrum of tumor-associated viruses. These findings enhance our understanding of factors cooperating with BRAF inhibition that accelerate keratinocyte oncogenesis as well as broaden the knowledge base of multifactorial mediators of cancer in general.