Maori queen Te Arikinui Dame Te Atairangikaahu is undergoing dialysis treatment -- with the Tainui tribe today issuing a rare public statement confirming persistent rumours she is suffering a serious health complaint.

However, Dame Te Ata's private secretary Taini Rutene was at pains to say the 74-year-old monarch's life was not in immediate jeopardy, though she would not confirm what conditions had led to dialysis treatment, which cleans a patient's blood when the kidneys begin to fail.

The Waikato Times understands Dame Te Ata has been receiving dialysis treatment for somewhere between two and three weeks. She spent a day in Waikato Hospital being assessed but went home for treatment.

In a very short media statement, Mrs Rutene said: "Dame Te Ata is undergoing medical treatment for a long-standing illness. There is no immediate concern (for her wellbeing). Medical staff from Waikato Hospital have organised dialysis treatment to manage her healthcare plan. Dame Te Ata wishes to thank Waikato Hospital staff for their support."

Waikato District Health Board staff are handling her day-to-day care at her home. Mrs Rutene would not confirm which home Dame Te Ata was staying at.

It is understood, however, she did not spend time in hospital over the Christmas and New Year period, and instead had friends and family visit at home.

Plans are continuing for Dame Te Ata's 40th coronation anniversary in May, another indicator the health issue is not immediately life-threatening.

Waikato Times medical columnist Leo Revell -- who is not the queen's doctor -- said dialysis was a process used to remove waste and additional fluid from the blood when the kidneys weren't doing the job properly. He said wear and tear on the kidneys, high blood pressure or diabetes could all lead to dialysis treatment.

Patients can live for 10 or 20 years with constant treatment, although younger candidates often consider kidney transplants an option, though it is not usually open to older patients, he said.

An example of that was rugby star Jonah Lomu, who is back playing rugby after a transplant and regular dialysis.