False about cellulitis
It is spreading inflammation of subcutaneous and fascial planes.  
 Infection may follow a small scratch or wound or incision.

Causative Agents: Commonly due to Streptococcus pyogenes and other Gram +ve organisms.
Sequelae

Infection can get localized to form a pyogenic abscess. 
Infection can spread to cause bacteraemia, septicaemia, pyaemia.    
Often infection can lead to local gangrene.