Walter Chaim1, Zeev Karpas, Avi Lorber. 1. Department of Obstetrics & Gynecology, Faculty of Health Sciences, Soroka University Medical Center, Ben Gurion University of the Negev, P.O. Box 151, Beer Sheva 84101, Israel. walter@bgumail.bgu.ac.il
Abstract
OBJECTIVE: To replace clinical diagnosis of bacterial vaginosis (BV) with a new and rapid analytical method based on ion mobility spectrometry (IMS). IMS is an instrumental technique for identifying compounds and determining their concentrations, based on measurement of the velocity of ions drifting through air at atmospheric pressure under the influence of an electric field. The technique is particularly sensitive to amines taking less than 2 min. STUDY DESIGN: Clinical examination of 174 samples determined 22 BV-positive and 152 BV-negative samples. IMS analyzed and recorded biogenic amine emanation mobility spectra of the 174 samples of vaginal discharge from duplicate swabs. RESULTS: IMS confirmed 21 (true positive BV) samples with 1 false negative (21/22, sensitivity=95.5%). Out of 152 samples, 150 were confirmed true BV-negative with 2 false positive samples (specificity=98.7%), PPV: 91.3%, NPV: 100%. CONCLUSIONS: The diagnostic procedure shows high accuracy and is technically simple and rapid. The trimethylamine level becomes an index of severity of the infection.
OBJECTIVE: To replace clinical diagnosis of bacterial vaginosis (BV) with a new and rapid analytical method based on ion mobility spectrometry (IMS). IMS is an instrumental technique for identifying compounds and determining their concentrations, based on measurement of the velocity of ions drifting through air at atmospheric pressure under the influence of an electric field. The technique is particularly sensitive to amines taking less than 2 min. STUDY DESIGN: Clinical examination of 174 samples determined 22 BV-positive and 152 BV-negative samples. IMS analyzed and recorded biogenic amine emanation mobility spectra of the 174 samples of vaginal discharge from duplicate swabs. RESULTS: IMS confirmed 21 (true positive BV) samples with 1 false negative (21/22, sensitivity=95.5%). Out of 152 samples, 150 were confirmed true BV-negative with 2 false positive samples (specificity=98.7%), PPV: 91.3%, NPV: 100%. CONCLUSIONS: The diagnostic procedure shows high accuracy and is technically simple and rapid. The trimethylamine level becomes an index of severity of the infection.