(CNN) -- An Ohio man intended to save the life of his older sister by donating a kidney to her -- a sacrifice on his part that ended in vain a year ago when a nurse mistakenly threw away the donated organ.
Paul Fudacz Jr. and his sister, Sarah, say the University of Toledo Medical Center "utterly botched" their kidney transplant surgery.
The medical center this week said it has "worked hard to learn from this incident" and apologized to the family.
But on Tuesday it asked that a lawsuit be dismissed and denied claims of gross negligence and failure to meet accepted standards of care.
The civil complaint contends Paul Fudacz's right kidney was considered a "perfect match" for his sister, then 24, who reportedly suffered from end-stage renal disease.
During the brother's surgery on August 10, 2012, his kidney was placed in a "slush machine" until it could be moved to his sister's room, where she'd yet to undergo her surgery.
A nurse, who was cleaning up, had just returned from a lunch break and thought the kidney was already in Sarah's room when she discarded the machine's contents, according to the lawsuit. While the kidney was later recovered, it couldn't be used because it had been thrown away with other infected or unsterile medical waste, the Fudacz family alleges.
Sarah Fudacz required additional dialysis and four dialysis-related surgeries before she received a replacement kidney three months later, the lawsuit states.
"When compared to Paul Jr.'s kidney, Sarah's new kidney is a poorer match and of poorer quality," and she has a higher risk of rejecting it over time, the lawsuit claims.
The pair's parents also claimed they suffered emotional distress and a "loss of consortium," or loss of family relationships.
But the Ohio attorney general contends parents of adult children and siblings cannot make such a claim about loss of consortium in such a case.
Each of eight Fudacz family members -- including four other siblings -- are seeking in excess of $25,000.
Dr. Jeffrey Gold, chancellor and executive vice president for health affairs, University of Toledo Medical Center, said the university "continues to express the sorrow that we feel that this unfortunate incident occurred. We apologize sincerely."
"While the legal realities of this situation are complex and ongoing, we have worked hard to learn from this incident and have spread the lessons widely to try to make hospitals and transplant programs safer across the country."
In the wake of the incident, the hospital temporarily suspended its live kidney donor program. It has since resumed operations.
The nurse involved in the incident retired from the hospital. The surgeon in charge of the planned transplant no longer directs the kidney transplant program but continues to perform them and remains a professor, the University of Toledo Medical Center said.