Here, we conducted a study to develop a dengue scoring system to predict pleural effusion and/or ascites using laboratory parameters, such as the degree of hemoconcentration, lowest albumin concentration at the critical phase, degree of hypoalbuminemia, lowest platelet count, elevated ratio of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and sodium concentration at critical phase. Here, ALB is linked to Pleural effusion.