GM-CSF acts at early differentiation processes at myeloid progenitors or resting monocytes [49] . An additional stimulus may be required to activate monocytes or dendritic cells in order to produce proinflammatory cytokines [50] . GM-CSF was associated with hypotension as well as MCP-1, likely acting both in concert, contrasting with MIP-1β, once more associated with good prognostics. MCP-1 was earlier detected in DHF patients [51] but for the first time we reported clinical and laboratory findings associated with severity.