Fight with disease in the beginning, in hospital room (4)
I believe the answer is:
ward
'hospital room' is the definition.
(I've seen this before)
'fight with disease in the beginning' is the wordplay.
'fight' becomes 'war' (warring is a kind of fighting).
'with' says to put letters next to each other.
'disease in the beginning' becomes 'd' (I can't justify this - if you can you should believe this answer much more).
'war'+'d'='WARD'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for ward that I've seen before include "Old guard" , "Division of borough" , "number of patients" , "Councillor's area" , "zone for votes" .)