An Integrated and Multi-Target Nucleic Acid Isothermal Analysis System for Rapid Diagnosis of Vulvovaginal Candidiasis

Abstract

Rapid identification of Candida species is significant for the diagnosis of vulvovaginal candidiasis (VVC). An integrated and multi-target system for the rapid, high-specificity, and high-sensitivity detection of four Candida species was developed. The system consists of a rapid sample processing cassette and a rapid nucleic acid analysis device. The cassette could process the Candida species to release nucleic acids in 15 min. The released nucleic acids were analyzed by the device as fast as within 30 min, using the loop-mediated isothermal amplification method. The four Candida species could be simultaneously identified, with each reaction using only 1.41 µL of reaction mixture, which was low cost. The RPT (rapid sample processing and testing) system could detect the four Candida species with high sensitivity (<2 CFU/reaction) and high specificity. The system also processed and analyzed 32 clinical samples, giving the results with high clinical sensitivity and specificity. Hence, the system was a significant and effective platform for the diagnosis of VVC. Furthermore, the period of validity of the reagents and chips used in the system was >90 days, and the system could also be used for the detection of bacteria.

Loop-Mediated Isothermal Amplification (LAMP): Potential Point-of-Care Testing for Vulvovaginal Candidiasis

“…In the same way, we performed at least 3 independent replicates for each sample. For the specific screening process and results, refer to Jin XY et al [17]. In our preliminary experiment, Candida was detected in 18 VVC clinical samples, including 9 C. albicans, 5 N. glabratus, 3 C. tropicalis and 1 C. parapsilosis, with a sensitivity and specificity of 100% [17].…”

“…For the specific screening process and results, refer to Jin XY et al [17]. In our preliminary experiment, Candida was detected in 18 VVC clinical samples, including 9 C. albicans, 5 N. glabratus, 3 C. tropicalis and 1 C. parapsilosis, with a sensitivity and specificity of 100% [17]. At the same time, in order to eliminate the effects of contamination from sample processing step and amplification, we completed the step of sample processing, step of LAMP mixture preparation, step of template supernatant addition into the mixture, and step of real-time detection in four independent spaces.…”

“…In this study, 202 clinical samples were used to verify the LAMP method of VVC proposed by Jin XY and Li M et al [17]. We simultaneously tested for multiple Candida species and achieved 100% specificity and a comparable sensitivity.…”

“…. parapsilosis, with a sensitivity and specificity of 100% [17]. At the same time, in order to eliminate the effects of contamination from sample processing step and amplification, we completed the step of sample processing, step of LAMP mixture preparation, step of template supernatant addition into the mixture, and step of real-time detection in four independent spaces.…”

A microfluidic-chip-based system with loop-mediated isothermal amplification for rapid and parallel detection of Trichomonas vaginalis and human papillomavirus

“…Several studies have reported that DNA of T. vaginalis and HPV can be successfully extracted through a heating treatment in a suitable lysis buffer, 16,43,44 and such a pyrolysis method is easy to implement on a syringe-like structure developed in our previous work. 45 Therefore, by integrating a sample processing cassette equipped with a heating module, our system can be enhanced into a sample-in and result-out POCT device, enabling rapid and simultaneous detection of both T. vaginalis and HPV. Furthermore, by preloading LAMP primers of other targets, our microfluidic chip system can be applied to various fields, including the diagnosis of other diseases, water monitoring, and food security.…”