Cristin Gildea lounged on her mother's bed, a thin tube snaking 3 feet from her chest to a small tape-recorder-sized device.

The device is a pump, and for 24 hours a day it delivers life-sustaining medicine into the arteries supplying the 10 year-old Columbia girl's lungs.  Wherever Cristin goes -to school, to play the piano, to sleep - the pump goes.

In the fight to keep the fifth-grader alive, Cristin and her mother, Donna Gildea, shoulder the load - one carrying the 3 pound pump in a small backpack, the other energetically raising awareness and money.

The fight is against primary pulmonary hypertension, a rare affliction that scars the lungs' arteries, tightening the blood vessels like someone squeezing a garden hose.  Eventually it blocks the flow of blood and leads to heart failure.

"I don't want to sound like a crazed mother," said Donna Gildea.  "But we need awareness of this.   We need a cure."

A mix of frenetic mother and reasoned businesswoman, Donna Gildea talks about funding the PPH Cure (of which she is director of development), caring for her daughter, running a business and chasing three puppies around the family's Harper's Choice townhouse.

Cristin, as quiet as her mother is active, dangled her white-and-black school shoes over the bed.

"She's just high-strung," Cristin said of her mother.

Later, as the melodies of Cristin playing Beethoven on the family's grand piano drifted to Donna Gildea's basement office, she recalled the frantic weeks in October 1996 when they learned of Cristin's illness.  Cristin's father, Charles, Donna's ex-husband, noticed a bulge in   Cristin's chest.

"Thank God she's thin," Donna Gildea recalled.  "We might not have even noticed."

Cristin's doctor referred the family to Johns Hopkins Hospital, where physicians spoke about heart-lung transplants and offered little advice about treatment - until one physician mentioned a specialist in New York.

The Gildeas made an appointment with Dr. Robyn Barst, director of the Children's Pulmonary Hypertension Center at Columbia Presbyterian Medical Center, the nation's primary authority on PPH in children.

Without treatment, most children die within a year of diagnosis, Barst told the family.  Tests showed Cristin would not respond to oral mediation.  She needed a drug that opens the lungs' arteries but dissolves quickly, meaning it must be injected into the bloodstream.

So Cristin carries her pump.   But that is a stopgap measure designed to put off the need for a lung or heart-lung transplant, the only known cure for PPH.  Barst says some patients have used the pump for as long as eight years, and have gotten healthier.

This is a horrible, horrible disease," Barst said.  "We need to find a cure."

PPH affects about 5,000 people nationwide -mostly women ages 21 to 40.   Its cause is unknown.

Treatment is costly, about $150,000 a year.  The Gildeas are fortunate - insurance pays about 85% of the bills.   Other PPH patients across the country are either suffocating from debt or have simply surrendered.

Not the Gildeas.

While they say the treatment was an ordeal at first, it has almost become routine.

One recent morning, Donna Gildea rose early and entered her walk-in closet, now turned into a semi-sterile room.

She quickly cleaned several small counters with alcohol, then withdrew the drug Prostacyclin from four vials with a syringe before mixing it with a dilutant and injecting the solution into a small container.  It fits snuggly in Cristin's pump and lasts 24 hours.

Side effects of the medication leave Cristin, who is freckle-faced with reddish-orange hair, with deep red lips and flushed palms.

The morning shower was difficult, with Cristin and her mother cleaning her chest connection with alcohol and retaping the tube afterwards.  Dona Gildea wore a mask and rubber gloves.

About 8 a.m. Cristin and her sister Rachel, 8, piled into their mother's car - license tag CUREPPH - and drove to St. Louis Roman Catholic School in Clarksville, where school administrators say about $5,000 from the school's recent annual fund-raiser will be turned over to PPH research.

At her class, Cristin took several asthmatic-like breaths as the teacher waited.

"I usually let the class get settled for a few minuets," said the teacher.  "That gives Cristin time to catch her breath."

During recess, while other girls chased boys on the playground or kicked soccer balls, Cristin sat in the library working on fractions and a coloring assignment.  Friends joined her.

"We don't mind missing recess," said Amanda Kingston, 10, one of Cristin's best friends.  "We just work on homework or talk."

Eating their bag lunches in the school's small cafeteria.  Cristin and company discussed living with PPH, or rather, trying to ignore it.

It's just not something we talk about," said Kristin Moore, 10.  "We know it's a really scary disease, that if she runs to fast, it hurts.  We want to do a lot of things but can't."

At home, in her mother's office, Cristin began pecking at a typewriter.  She was writing a speech for her classmates.

"I'm here to tell you about my disease, PPH,"  Cristin typed.  "It is an illness that makes my lungs tight.  My heart is trying to push blood into them.  It is a life-threatening illness."