Campaigners have hailed a coroner's decision to record chronic fatigue syndrome as a cause of death.
Sophia Mirza suffered from the illness for six years
The New Scientist reported that it is the first time that CFS, also known as ME, has been given as an official cause of death in the UK.
The Brighton and Hove coroner ruled on 13 June that Sophia Mirza, 32, of Brighton, died from "renal failure as a result of chronic fatigue syndrome".
Campaigners believe the verdict proves that CFS/ME is a physical illness.
Groups such as Invest in ME and the ME Association say the coroner's ruling shows that CFS/ME is a neurological condition
Art graduate Ms Mirza suffered with CFS for six years before she died in November last year.
The condition affects the immune and central nervous system and is characterised by debilitating chronic fatigue.
Her mother, Criona Wilson, 63, of Brighton, said her daughter had "lived in solitary confinement for five years".
Evidence given by doctors to the coroner showed Sophia's spinal cord was inflamed, indicating a physical manifestation of CFS/ME.
"You can't put that down to psychosis in any way whatsoever," said Dr Charles Shepherd, of the ME Association.
Sue Waddle, of Invest in ME, hopes the verdict on Sophia's death, recorded by Brighton and Hove coroner Veronica Hamilton-Deeley, will encourage the government to fund research.
In the 1980s, ME (myalgic encephalomyelitis) was known derisively as "yuppie flu" for its tendency to be diagnosed in work-hard, play-hard, young professionals.