Can start with a non-descript blanching maculopapular rash. The classic meningococcal rash is described as looking "flea-bitten", which is to say that the rash is slightly lumpy, with a central petechia on each lesion.
More advanced disease is suggested by large purpuric areas, and this can progress to necrosis and peripheral gangrene (purpura fulminans).
See Emergencies.