| Title: | Diurnal variation in expired breath volatiles in malaria-infected and healthy volunteers |
| Author(s): | Berna AZ; McCarthy JS; Wang XR; Michie M; Bravo FG; Cassells J; Trowell SC; |
| Address: | "Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, United States of America. CSIRO Health and Biosecurity, Clunies-Ross Street, Acton ACT 2601, Australia" |
| ISSN/ISBN: | 1752-7163 (Electronic) 1752-7155 (Print) 1752-7155 (Linking) |
| Abstract: | "We previously showed that thioether levels in the exhaled breath volatiles of volunteers undergoing controlled human malaria infection (CHMI) with P. falciparum increase as infection progresses. In this study, we show that thioethers have diurnal cyclical increasing patterns and their levels are significantly higher in P. falciparum CHMI volunteers compared to those of healthy volunteers. The synchronized cycle and elevation of thioethers were not present in P. vivax-infection, therefore it is likely that the thioethers are associated with unique factors in the pathology of P. falciparum. Moreover, we found that time-of-day of breath collection is important to accurately predict (98%) P. falciparum-infection. Critically, this was achieved when the disease was asymptomatic and parasitemia was below the level detectable by microscopy. Although these findings are encouraging, they show limitations because of the limited and logistically difficult diagnostic window and its utility to P. falciparum malaria only. We looked for new biomarkers in the breath of P. vivax CHMI volunteers and found that a set of terpenes increase significantly over the course of the malaria infection. The accuracy of predicting P. vivax using breath terpenes was up to 91%. Moreover, some of the terpenes were also found in the breath of P. falciparum CHMI volunteers (accuracy up to 93.5%). The results suggest that terpenes might represent better biomarkers than thioethers to predict malaria as they were not subject to malaria pathogens diurnal changes" |
| Keywords: | Adult Biomarkers/analysis Breath Tests/*methods *Circadian Rhythm *Exhalation Female *Healthy Volunteers Humans Malaria/*diagnosis Male Periodicity Plasmodium falciparum/physiology Plasmodium vivax/physiology Predictive Value of Tests Sulfides/analysis Te; |
| Notes: | "MedlineBerna, Amalia Z McCarthy, James S Wang, X Rosalind Michie, Michelle Bravo, Florence G Cassells, Julie Trowell, Stephen C eng Clinical Trial Research Support, Non-U.S. Gov't England 2018/08/22 J Breath Res. 2018 Sep 19; 12(4):046014. doi: 10.1088/1752-7163/aadbbb" |
