PITTSBURGH (AP) _ Saul Pineda took two jobs to start paying the nearly $400,000 cost of his son's liver transplant. His wife, Angelica, found work as well, and friends and strangers donated money.

But last month, the Immigration and Naturalization Service told them they must leave the country by July 29.

Although 9-year-old Soel Pineda no longer needs medical care in the United States, his parents say it will be extremely difficult to repay their debt from their homeland, Venezuela, where the national currency has lost much of its value.

``I don't know what we are going to do,'' Mrs. Pineda said. ``I am a little sad. A little nervous. I hope we can work it out.''

Soel, one of the Pinedas' three children, received a liver transplant in August 1995 at Children's Hospital. Because he arrived as an emergency case, his family had not made prior arrangements to pay.

The Pinedas took jobs at Miller Process Coating, which makes screen printing equipment in Monroeville, a suburb of Pittsburgh. Pineda works in the machine shop in addition to his job as a telemarketer. His wife works in the office and interprets for Spanish-speaking customers.

In the past 19 months, the Pinedas have repaid $13,000.

``They are trying to pay back a debt,'' said their boss, Daphne Miller. ``They didn't have to do that. They could have said, `Thank you very much, United States, for your services. We are out of here.'''

The Pinedas say that in Venezuela, his earnings as manager of a car dealership and hers as a nurse could not have paid the $400 a month needed for Soel's anti-rejection medicine.

George R. Hess, an officer of the immigration service in Pittsburgh, said the Pinedas can appeal their case to an immigration judge. If they can prove compelling circumstances, the judge may extend their stay.

DeAnn Marshall, a spokeswoman for Children's Hospital, said Soel does not have to stay in Pittsburgh, although he must take his medicine and make frequent visits to his doctor in Venezuela.

``He's basically at a point where he's medically stable and has been for a long time and can return home,'' Ms. Marshall said. ``We do have an outstanding bill, but we're not holding them here in Pittsburgh.''