Background Approximately 70% of cervical carcinoma cases show the presence of high-risk Human Papilloma Virus (HPV), especially HPV-16 and HPV-18, and can be used to stratify high risk patients from low risk and healthy. Currently, molecular biology techniques such as polymerase chain reaction (PCR) are used to identify the presence of virus in patient samples. While the methodology is highly sensitive, it is labor intensive and time-consuming. Alternative techniques, such as vibrational spectroscopy, has been suggested as a possible rapid alternative. Therefore, in this study, we evaluate the efficiency of cervical fluid Fourier Transform Infrared spectroscopy (FTIR) in patient risk stratification informed by PCR. Methods Cervical fluid samples (n = 91) were obtained from patients who have undergone routine Papanicolaou (Pap) test. Viral genome was identified and classified as high/low-risk by PCR-Restriction Fragment Length Polymorphism (PCR-RFLP). FTIR spectra were acquired from samples identified by PCR-RFLP as No-HPV (n = 10), high-risk HPV (n = 7), and low-risk HPV (n = 7). Results Of the 91 samples, was detected the viral genome by PCR in 36 samples. Of these 36 samples, nine samples were identified to contain high-risk HPV (HR-HPV) and nine samples were found to have low-risk HPV (LR-HPV). The FTIR spectra acquired from No-HPV, LR-HPV, and HR-HPV showed differences in 1069, 1437, 1555, 1647, 2840, 2919, and 3287 cm -1 bands. Principal Component Analysis (PCA) showed distinct clusters for No-HPV and HR-HPV and No-HPV and LR-HPV, but there was significant overlap in the clusters of HR-HPV and LR-HPV. PCA-Linear Discriminant Analysis (PC-LDA) after Leave One Out Cross Validation (LOOCV) classified No-HPV from HR-HPV and No-HPV from LR-HPV with 100% efficiency in the 1400-1800 cm -1 spectral range. LOOCV classifications for LR-HPV and HR-HPV from each other were 71 and 75%, respectively, in the 2800-3400 cm -1 spectral range. Conclusions The results highlight the high sensitivity of PCR-RFLP in HPV identification and show that FTIR can classify samples identified as healthy, low, and high-risk samples by PCR-RFLP. General significance We show the possibility of using FTIR for initial cervical cancer risk stratification followed by detailed PCR-RFLP investigations for suspect cases.

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Human papillomavirus (HPV) infection is the most common sexually transmitted disease worldwide and several studies have proven the close relationship between HPV and the development of cervical cancer. Several tests are currently performed for early and reliable diagnosis, in which the cervical cytology evaluation by the Papanicolaou method is highlighted. However, errors in the collection and misinterpretation of cell differentiation degree in smear by the pathologist result in incorrect or inaccurate results. Considering these points, it is of utmost importance to develop new technologies that perform accurate and reliable diagnosis and that present financial advantages and accessibility. Currently, molecular biology assays are excellent detectors of viral DNA, but it presents disadvantages, such as the need for high financial resources to gain access. Therefore, this review has the objective of highlighting the main diagnostic techniques that are already being used, such as specific kits for the detection of high-risk HPVs, or methodologies that are still in the study phase, but which already present good results, such as the application of physical FTIR spectroscopy principles and ultrasensitive biosensors.

Human Papillomavirus (HPV) infection is the main precursor of cervical cancer. Pap Smear is the main diagnostic method of this neoplasm by cytological analysis, however presents a high rate of false-negative cases. This study aimed to verify if micronucleus (MN) frequency test and the Fourier Transform Infrared (FTIR) Spectroscopy analysis may be alternative useful techniques to detect HPV in cervical fluid. Fifty samples with normal cytology obtained from patients after cytopathological examination were divided into two groups based on the presence or absence of HPV by previous analysis of molecular biology. Of the fifty samples analyzed, 46% showed the presence of MN in the cells. The frequency of MN observed was higher in the samples with HPV positive and was related with age, use of oral contraceptives and use of alcoholic beverages (p <0.001). FTIR analysis spectra showed high peak DNA and proteins in samples with a high frequency of MN (1170cm-1; 1516cm-1; 1404cm-1; 1473cm-1) compared with samples with absence of MN, probably due to chromosomal histones and MN constituents. However, no statistically significant difference was observed between these groups considering that the FTIR is a screening test and not specific. Thus, by the FTIR technique it was not possible to classify the samples by the spectral differences presented. The MN test can be considered a screening test for the detection of HPV, being possible to use it in clinical practice because it is a practical, simple, low-cost and non-invasive method. However, it is important to carry out studies in larger sample groups to investigate the application of the MN test and FTIR spectroscopy in the diagnosis of this infection and in the application in the prevention of cervical cancer.