Clinical Microbiology: Open Access

Potential use of total serum nitrite and nitrate (NOx) level in dengue patients as a prognostic marker of dengue hemorrhagic fever

Joint Event on 25^th Asia Pacific Biotechnology Congress & 3^rd International Conference on Medical and Clinical Microbiology

May 01-02, 2019 Kyoto, Japan

Maheshi Mapalagamage, Shiroma Handunnetti, Sunil Premawansa, Gayani Premawansa, Sharmila Thillainathan, Tharanga Fernando, Karunayokiny Kanaphathippillai, Rajitha Wickremasinghe and Aruna Dharshan De Silva

University of Colombo, Sri Lanka Colombo North Teaching Hospital, Sri Lanka University of Kelaniya, Sri Lanka Genetech Research Institute, Sri Lanka

Scientific Tracks Abstracts: Clin Microbiol

Abstract:

Use of total nitrite plus nitrate (NOx) and nitrite (NO2-) separately as surrogate markers for serum nitric oxide in severe dengue and their longitudinal changes along with the progression of infection was studied. Deproteinized sera from confirmed Dengue Fever (DF, n=145) and Dengue Hemorrhagic Fever (DHF, n=74) patients on admission-A, critical-C, discharge-D, and convalescence-CON stages and from age-gender matched healthy individuals (HC, n=77) were taken to assess NO2- and NOx levels using Griess and modified Griess assays. Serum NOx in DHFA was significantly lower compared to DFA (p<0.001). HC had the lowest NOx and NO2- compared to all patient categories (p<0.001) except NO2- in DF-CON and DHF-CON and NOx in DHF-CON. A strong significant positive correlation between serum NOx levels and NO2- was observed in DHFA (p<0.000, r=0.599, Pearson correlation), DHFC (p<0.004, r=0.573) and DHFD (p=0.425, r=0.008) patient categories. Receiver Operating Characteristic (ROC) curve analysis was done to seek the prognostic value the test of serum NOx in predicting DHF on admission. Serum NOx and NO2− in DHF patients admitted on fever day 3 (DHFA-3) was significantly lower compared to DFA-3 (p<0.050). Cut-off values of 4.46 μM for NOx (91.3% sensitivity and 80.1% specificity) and 1.25 μM for NO2- (75.0% sensitivity and 73.3% specificity) were obtained for day 3 of fever. In DHF patients, the lower NO levels may have made a more favorable environment for the virus to flourish. This may have resulted in a high viral load which may have increased the adverse pathophysiologic process in the body leading to increased severity. Therefore, serum NOx may be used as potential prognostic marker of DHF in patients presenting with DF in the early stage (on day 3 of fever) of the disease.

Biography :

Maheshi Mapalagamage has completed her BSc in Zoology from University of Colombo, Sri Lanka and is currently pursuing her PhD at Institute of Biochemistry, Molecular Biology and Biotechnology, University of Colombo. Her PhD is based on investigating prognostic markers for severe dengue infection with respect to oxidative stress and endothelial dysfunction and underling immunopathogenic mechanisms. She is also working as an Assistant Lecturer at Department of Zoology and Environment Sciences, University of Colombo, Sri Lanka.

E-mail: sasika1212@gmail.com