Patients for analysis of LTE4 levels in early illness
120 adult patients with acute dengue infection were recruited from the National Institute of Infectious Diseases during the years 2018-2019, following informed written consent. The duration of illness at the time of recruitment and obtaining blood and urine samples was ≤ 4 days of illness in 120 patients and between 5 to 6 days in 54 patients. The first day of illness was considered as the first day they developed fever. Any individual who had chronic liver disease, chronic renal disease and pregnant women were excluded from the study.
The patients were assessed several times a day for changes in blood pressure, urine output, presence of bleeding manifestations and possible leakage. Ultrasound scans were performed to determine the presence of fluid leakage in pleural and peritoneal cavities. All the clinical parameters (e.g. blood pressure, temperature, heart rate, pulse pressure and fluid leakage) and investigation results such as FBC, liver function tests, serum electrolytes were recorded throughout the course of illness. The severity of dengue infection was classified according to the 2011 WHO dengue diagnostic criteria(18). Accordingly, patients with a rise in haematocrit above ≥ 20% of the baseline haematocrit or with clinical or ultrasound scan evidence of plasma leakage were classified as having DHF. Based on this classification, in those recruited in ≤4 days of illness (n=120), 72 patients had DF and 48 DHF and those recruited between day 5 to 6 (n=54), 27 had DF and 27 had DHF. Nineteen healthy individuals who did not having any atopic illnesses (allergic rhinitis, asthma, food allergies or eczema), and who were not on antihistamines or steroids were recruited as healthy controls.