There's more heartbreak ahead for Duffy as she is told she is in the early stages of vascular dementia by a neurologist in tomorrow night's episode (23.03.19).
After suffering falls and experiencing problems with her mood and memory she went for tests and an MRI scan.
The nurse was diagnosed with early-onset dementia back in January but the bad news keeps coming for the Casualty favourite.
When Duffy finally gets her results in tonight's show, her world will be turned upside down when the doctor confirms she's in the early stages of vascular dementia.
As a nurse, Duffy is encouraged to let her employer know of the news and to talk to someone about her diagnosis.
Duffy then tells her estranged husband Charlie the sad news and he struggles.
Charlie then takes Duffy off night shifts and any difficult duties.
Previously, show producer Simon Harper said: "We are mindful of telling them authentically and sensitively, which is why we are always so grateful to fantastic charities like Dementia UK, who give us invaluable advice."
Simon also heaped praise on Cathy for her stellar performance as Duffy.
He is quoted by The Sun's Bizarre TV column as saying: "Depicting this cruel disease will help raise awareness, and Cathy is knocking it out of the park with her heart-breaking performance."
Duffy got married to nurse Charlie in 2017, however the pair went through a rough time last year after Duffy cheated with her childhood sweetheart Bill.
The pair have since separated but continue to work together.
If this storyline effects you or someone you know, please visit the Dementia UK website.
Casualty airs at 8:25pm on Saturday's on BBC One
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