vim plugin for coloring macros -

Is there a way to highlight variables / macros defined in VIM? Is there any plugin that does this, for example.

  # MonitoringWatch conversion_monitoring (monitoring);   
 In the above example, is there a way to highlight  MONITORING_ON ?  
 (I'm using VIM on windows when CTGS is enabled.)  
 thanks   
 
 
 This plugin is worth mentioning, that additional update of the automatic tag file supports the dynamic syntax highlighting tag events.