Source : Webster's Revised Unabridged Dictionary (1913)

Sequela \Se*que"la\, n.; pl. {Sequel[ae]}. [L., a follower, a
   result, from sequit to follow.]
   One who, or that which, follows. Specifically:
   (a) An adherent, or a band or sect of adherents. ``Coleridge
       and his sequela.'' --G. P. Marsh.
   (b) That which follows as the logical result of reasoning;
       inference; conclusion; suggestion.

             Sequel[ae], or thoughts suggested by the preceding
             aphorisms.                           --Coleridge.
   (c) (Med.) A morbid phenomenon left as the result of a
       disease; a disease resulting from another.

Source : WordNet®

sequela
     n : any abnormality following or resulting from a disease or
         injury or treatment; "paralysis is one of the sequelae of
         poliomyelitis"
     [also: {sequelae} (pl)]