When you have Dengue fever, the following condition will occur, and the following levels generally characterize it:
Leucopenia (White Blood Cells (WBC) < 5000 cells/mm3),
Thrombocytopenia (< 150,000 cells/mm3),
Rising hematocrit (5–10%) should not be any evidence of plasma leakage.
The presence of IgM in Dengue fever means you have got Dengue fever very recently. The IgM antibody test will be positive even for the Chikungunya test. Thus, confirmation has to be done by antigen-specific test. If IgG is positive and IgM is negative or low, that means you had Dengue sometime in the past.