Wards at Dalriada Hospital may never reopen if temporary closure plans are not halted, the High Court heard on Tuesday.
A judge was also told public consultation announced after the decision to shut the intermediate care and multiple sclerosis respite wards will be “pushed through as a fait accompli”.
Lawyers seeking to stop the reduction in services at the facilities in Ballycastle, Co Antrim claimed the plans were unlawful and had united the five main political parties in condemnation.
They set out their case as they sought a court order that new patients are to still to be admitted pending the outcome of the legal challenge.
Under current plans the two units are to close until March next year due to cuts to the Northern Health and Social Care Trust’s budget.
The MS ward is the only dedicated respite unit in Northern Ireland for those with the debilitating condition.
It can accommodate 12 patients while the intermediate care ward can hold another 20.
According to the Trust alternative respite options will be made available.
Judicial review proceedings against the temporary closure have been brought by Philomena McKay, a 54-year-old MS sufferer who has been using the Dalriada facility for years.
Her lawyers have already cleared the first stage in their legal action amid claims that staff or patients were never consulted on the plans.
But they returned to court on Tuesday to challenge the block on new admissions while the legal battle continues.
David Scoffield said: “The concern of the applicant and others in the community generally in Ballycastle is that this closure is, or will become, a permanent closure.
“There have been previous attempts to close Dalriada Hospital by the predecessors of the Northern Trust, and they have only been prevented by public outcry.”
Those suspicions have been shared by all the political parties calling for Health Minister Jim Wells to reverse the plans, according to the barrister.
Quoting from an Assembly debate on the issue, he claimed there had been “extraordinary” unity at Stormont that the plans amounted to “permanent closure by another form”.
Mr Scoffield said: “This is quite unusual, if not unique, to have cross-party condemnation of what the Minister has done.”
In a critical assessment of the consultation exercise now announced, he claimed: “The minister is now trying to close the door after the horse has bolted, and indeed after he has shooed the horse up the lane.”
Mr Justice Treacy was also told the closure is not merited through any financial savings.
Although the Trust was originally faced with finding ways to deal with a £30 million deficit, the court heard the most recent figures point to making savings of £6.9m.
Closing the Dalriada units will account for just over £550,000, according to Mr Scoffield.
“These are not expensive facilities to run,” he added.
Tony McGleenan QC, responding for the health authorities, argued that no MS patients are scheduled for respite at Dalriada until February.
By that stage both the consultation process and legal challenge may have been concluded, he said.
Any patients requiring urgent respite care will be cared for at two facilities in Cushendun and Garvagh, the court heard.
Although there is no current intake of patients for the intermediate beds, Mr McGleenan stressed the Trust has put in place alternative arrangements.
“Any patient who requests it will be catered for,” he said.
The barrister also contended that political representatives can hold the minister to account through the Health Committee at Stormont.
He added: “In one view that’s an entirely more appropriate forum.”
Reserving judgment on the application for an interim order, Mr Justice Treacy said he will give his decision on Thursday.