Doctor from Middle East upset detectives (5)
I believe the answer is:
medic
'doctor' is the definition.
(doctor is a type of medic)
'middle east upset detectives' is the wordplay.
'middle east' becomes 'me' (abbreviation for Middle East).
'upset' is a reversal indicator.
'detectives' becomes 'CID' (abbreviation for Criminal Investigation Department).
'cid' written backwards gives 'dic'.
'me'+'dic'='MEDIC'
'from' acts as a link.
(Other definitions for medic that I've seen before include "Physician (informal)" , "What was Basutoland" , "Eg, doctor" , "He may offer treatment" , "Word for 'doctor'" .)