Late last fall a young woman sought treatment at the Spanish Catholic Center's medical clinic on Mount Pleasant Street in Northwest Washington. She was pregnant and epileptic. The clinic doctor decided she needed to see a specialist -- a neurologist -- because epilepsy can create complications in a pregnancy.

But the woman, a recent immigrant from Costa Rica, had no health insurance. She and her husband worked hard -- she as a baby sitter, he as a waiter -- but they barely made enough money to pay for room and board, much less specialized medical care.

Through a new health care network for the poor, the clinic was able to refer her to Dr. Francis Mayle, a Bethesda neurologist, who saw her for free.

Sister Martha Gardiner, a nurse at the Spanish Catholic clinic, said the woman "was just in awe that the doctor would take so much time with her, knowing she couldn't pay. She'd never seen such care. These people aren't used to that kind of treatment."

The young woman gave birth to a healthy 6-pound, 2-ounce baby on Jan. 30. While the pediatrician at Spanish Catholic clinic keeps close watch on the baby, Mayle continues to see the mother for free.

From a tiny cubicle in the Associated Catholic Charities headquarters in Northeast Washington, Sister Mary Louise Wessell coordinates the Archdiocesan Health Care Network, which draws from the volunteer services of 165 physicians and 20 dentists in the Washington area to help provide medical care to those who can't afford it.

Three nonprofit health clinics in refer patients to the network when they need more specialized care than the clinics, which operate on a shoestring budgets with overworked doctors, are able to provide. Network health professionals also volunteer at two local shelters for the homeless.

Wessell, who keeps track of the doctors and referrals on handwritten sheets of college-ruled paper in a fat blue three-ring binder, matches sick patients with specialists. The doctors will usually see the patients in their offices, Wessell said, and the care they get differs from what the doctor's regular patients receive only in that there is no charge, or a minimal one.

The network will serve anyone who needs help, regardless of race, religion or citizenship.

Many of the patients who seek help are undocumented immigrants, afraid to seek help from government agencies, says John Alvarez, director of parish and community relations for Associated Catholic Charities. "They have terrible stress-related problems. They get sick and they're scared to go for help."

The roster of volunteer doctors includes a wide variety of specialists, including cardiologists, dermatologists, neurologists, pediatricians, obstetricians and radiologists. If a patient needs an X-ray, Wessell can locate a radiologist. If prescription drugs are needed, the network will find a way to provide them. There are a few nurses, including Wessell, who help teach preventive measures.

Last May, the network added dentistry to its services. The most recent addition is a donated van to help transport patients to the doctors' offices.

The Archdiocesan Health Care Network was born two years ago when Archbishop James A. Hickey decided to ask Catholic doctors to help devise a way to bring medical care to the poor, said Dr. Edmund Pellegrino, a professor of medicine at Georgetown University. Hickey called together a group of physicians, including Pellegrino, and asked them to tackle the problem. He recruited Pellegrino to be the committee's chairman.

The committee surveyed all the Catholic physicians in the area and asked them if they would be willing to do one of three things: help out in a clinic, see poor people in their offices free of charge or provide laboratory work or X-rays.

"We got commitments from 150 of them," Pelligrino says. "And with that we set up the network."

Pellegrino, who directs the Kennedy Institute of Ethics at Georgetown, says his goals for the network are modest -- "to get needed medical care to those who can't pay.

"Thirty-five million people in the nation are not covered by health insurance," a number that continues to grow, he says. "It seems that the national rhetoric changed six or seven years ago. We don't talk about a national health care system any more."

He has no illusions that the network can solve all the health care problems of the nation's poor, or even all of the Washington area's needy.

"But if we can get it going the way we hope to, it could be a model, and replicate itself elsewhere. To do that, we have to show that it works. So many things like this fail," Pellegrino says.

"My philosophy is to start small, to do one thing well before we go on to something else."

For that reason, he says, the advisory committee chose not to seek publicity until they felt the network was well-established.

"I'm cautious, but at the moment I think it's going well," Pellegrino says.

Wessell's fat notebook charting doctors and referrals is testimony to how well it's going. Since the network began in September 1984, she says, she has referred more than 700 patients to physicians. In addition, network doctors and nurses volunteered at Carroll House, a shelter for homeless men in Silver Spring. And as of January, volunteers have been working at Rainbow House, a Bethesda shelter for women.

Wessel estimated that by the end of February, three area radiologists had provided at least $19,000 in free X-rays.

The network still has needs. There is a shortage of obstetricians and gynecologists among the volunteers and also pediatricians and ear, nose and throat specialists. More nurses are needed.

Wessell is working with area hospitals to work out ways that patients who need surgery can be hospitalized for free. She could use some volunteers to help her in the office and she'd like to get a computer to keep track of the referrals.

Most of the doctors at this point are Catholic, but volunteers of any religion are welcome, Wessell says. Most of the doctors are from Maryland or the District, but volunteers from Virginia are also welcome.

Those who volunteer give unselfishly of their time, Pellegrino says. "They are willing and happy to do it."

"It is important for people to know that there are physicians who will do something like this. So many people have the impression that doctors are selfish and money-grubbing." For More Informantion

For more information or to volunteer, contact Sister Mary Louise Wessell, coordinator, Archdiocesan Health Care Network, Associated Catholic Charities, 2800 Otis St. NE, Washington, D.C. 20018. The phone number is 526-4100.