Background: Dengue infection is the most rapidly spreading mosquito-borne viral disease in the world and an estimated 50 million dengue infections reported annually. The pathogenesis of Thrombocytopenia in dengue fever (DF) is not clearly understood. Increased peripheral destruction of antibody coated platelets and acute bone marrow suppression were strongly suspected as the possible mechanism. This often leads to life threatening dengue hemorrhagic fever (DHF) and Dengue shock syndrome (DSS). Steroids are used in the treatment of Idiopathic thrombocytopenic purpura to increase the platelet count which is mediated by auto antibodies .This hypothesis would support the use of steroids in dengue fever.

Aim and objectives: The objective of this study was to test whether an intravenous high dose dexamethasone was efficacious in increasing the platelet count in acute stage of dengue fever with thrombocytopenia.

Methods: During the study period between June 2010 - 2011 in JSS Hospital Mysore, 127 patients were screened for dengue fever with thrombocytopenia (<50000/cumm) and 61patients were randomly allocated, 30 to the study group and 31 to the control group, in an open labeled study. The study group received intravenous dexamethasone 8mg initially followed by 4 mg every 8 h thereafter for 4 days and IV fluids whenever required. The control Group received only IV fluids and antipyretics whenever it was indicated. The daily measurement of platelet count was carried out in all patients from the day of enrolment to the fourth day of post treatment.

Results: The baseline data (age, sex, and the mean duration of the illness, Hb%, haematocrit, and platelets) were similar in both the groups. The analysis of variance (ANOVA) statistics showed a significant linear association of the mean platelet counts with the days in either group. The mean platelet counts increased steadily in both the groups from days 1 to 4: day1 (0.687), day2 (0.34), day3 (0.530) and day4 (0.844). There was no significant difference between the two groups.

Conclusion: We conclude that at a high dose dexamethasone regimen was not effective in achieving a higher rise in the platelet count in the acute stage of dengue fever.