RESUMEN
Human papillomavirus (HPV) primary screening is an effective approach to assessing cervical cancer risk. Self-collected vaginal swabs can expand testing access, but the data defining analytical performance criteria necessary for adoption of self-collected specimens are limited, especially for those occurring outside the clinic, where the swab remains dry during transport. Here, we evaluated the performance of self-collected vaginal swabs for HPV detection using the Cobas 6800. There was insignificant variability between swabs self-collected by the same individual (n = 15 participants collecting 5 swabs per participant), measured by amplification of HPV and human ß-globin control DNA. Comparison of self-collected vaginal swab and provider-collected cervical samples (n = 144 pairs) proved highly concordant for HPV detection (total agreement = 90.3%; positive percentage agreement = 84.2%). There was no relationship between the number of dry storage days and amplification of HPV (n = 68; range, 4 to 41 days). Exposure of self-collected dry swabs to extreme summer and winter temperatures did not affect testing outcomes. A second internal control (RNase P) demonstrated that lack of amplification for ß-globin from self-collected specimens was consistent with poor, but not absent, cellularity. These data suggest that self-collected vaginal samples enable accurate clinical HPV testing, and that extended ambient dry storage or exposure to extreme temperatures does not influence HPV detection. Furthermore, lack of ß-globin amplification in HPV-negative samples accurately identified participants who required recollection.
Asunto(s)
Virus del Papiloma Humano , Infecciones por Papillomavirus , Manejo de Especímenes , Adulto , Femenino , Humanos , Persona de Mediana Edad , ADN Viral/análisis , Detección Precoz del Cáncer/métodos , Virus del Papiloma Humano/aislamiento & purificación , Tamizaje Masivo/métodos , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/virología , Manejo de Especímenes/métodos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/virología , Vagina/virología , Frotis Vaginal/métodosRESUMEN
Two different laboratories evaluated growth and detection of mycobacteria and drug susceptibility testing of Mycobacterium tuberculosis by the BD Bactec MGIT 320 using the BD Bactec MGIT 960 (BD Diagnostics, Sparks, MD) as a reference method. Out of 359 processed sputum specimens for detection of mycobacteria, 99.7% were in agreement between the MGIT 320 and MGIT 960. Streptomycin (STR), isoniazid (INH), rifampin (RIF), ethambutol (EMB) (collectively known as SIRE), and pyrazinamide (PZA) drug susceptibility testing was performed on 89 clinical strains, prepared from both liquid and solid inocula. The results of SIRE and PZA were 100% reproducible between the two instruments tested at both laboratories.