The mother of a desperately-ill four-year-old Irish boy hopes to find out in the coming days whether their son fits the criteria for a life-saving double lung transplant in the US.

Little Cian McDonnell, who suffers from a rare and incurable condition, returned to Ireland with his family on Tuesday morning after being assessed over a week by specialists at Boston Children's Hospital for his suitability for the major operation.

A final decision on whether the Co. Meath youngster can be operated on is expected to be made following analysis of results of an upcoming liver biopsy.

Surgeons in Ireland will also insert a gastrostomy feeding tube into the youngster, whose recent loss of appetite has triggered a worrying weight loss.

After arriving back on Irish soil, his mother Lisa said: "Hopefully we will know in the coming week if Cian is definitely going to be put on the transplant list."

Update from Cians Mother: After 5 long days we came to the end of Cians assessment yesterday evening. The doctors Cian...

Posted by Hope for Cian on Dé Sathairn, 29 Lúnasa 2015

In an earlier Facebook post over the weekend, she had said: "The doctors Cian is under feel a lung transplant is an option but the last thing we need before a final decision is a liver biopsy.

"This will be done in Ireland at the same time as his gastrostomy feeding tube insertion. Cian needs the tube as his appetite is very poor recently and he has lost so much weight. This will optimise his strength if he goes to transplant.

"We will have a better overall picture after the liver biopsy. There are signs that his liver is not 100% normal."

His mother also admitted the latest developments had left both her and husband feeling "confused".

She added: "It's so unfair that Cian has gone through and is still going through so much and he's only four years old. He inspires us every day. He has such a love for life and for everybody around him. We are blessed to have this special little boy in our lives."

If the youngster is given the green light for the operation in Boston, the family still need to raise $1million to cover the costs of the procedure.

Time is not on the side of the youngster, whose family has previously been informed he has just months to live and must undergo the transplant as soon as possible.

His parents have admitted the operation in Boston represents their last hope of saving his life, after he was rejected for a double-lung operation at London's Great Ormond Street earlier this year.

The boy is believed to be the only child in Ireland to suffer from a severe bone marrow disorder, called Dyskeratosis Cognetia - a condition so rare it affects just one child in a million worldwide.

The disease left him permanently blind at the age of one. And despite successfully undergoing a bone marrow transplant two years ago, earlier this year, the youngster was diagnosed with another deadly condition which has caused severe deterioration to his lungs, called microscopic pumonary AVMS.

Donations can be made at Also, see 'Hope for Cian' on Facebook or visit the website.