Two doctors, one in New Orleans and one in Houston, have teamed to provide care for an infant girl with a condition so rare that one doctor has never seen it; the other has treated only a handful of such patients.

Kaydence Lusk, a bright-eyed little girl of 9 months, was born on May 23, 2012, and diagnosed five months later with a lung disease called surfactant protein C deficiency.

“The surfactant’s job in the lungs is to make it easier for us to breathe,” said Dr. Timothy Vece, the pediatric pulmonologist at Texas Children’s Hospital in Houston who diagnosed Kaydence in October.

Surfactant, made of proteins and lipids, lines the airspaces of the lungs and prevents the lungs from collapsing too much when a breath is exhaled, Vece said.

The protein C is one of four specialized proteins in surfactant; deficiencies in the proteins can cause severe breathing problems in newborns, according to the U. S. National Library of Medicine.

Kaydence takes several medicines, has a feeding tube and is on oxygen continuously to treat her symptoms.

One day in the future, in her early teens perhaps, she will need a double lung transplant.

“Generally, they need a lung transplant much earlier than we would have hoped for,” Vece said.

“We go day by day. If things change, you just change with it,” said Kaydence’s mother, Tammy Faucheux. “I’m just thankful she’s happy right now and feels good.”

Because Kaydence’s condition is so rare, it took months and many medical tests before Faucheux and her husband, Lionell Lusk, had answers.

“The not knowing was so bad,” Faucheux said.

From the time she was 2 weeks old, Kaydence cried, sometimes practically screaming, most of the time during her waking hours, her mother said.

The pediatrician at first thought the baby was allergic to her formula; several different formulas were tried consecutively, Faucheux said.

Not seeing any improvement for her infant daughter, Faucheux brought Kaydence back to the doctor and said, “Something is wrong with her.”

“I was taking her to the doctor three times a week,” Faucheux said.

Kaydence had begun to lose weight.

The doctor referred Kaydence to Children’s Hospital in New Orleans for bloodwork that showed, among other things, that Kaydence’s oxygen was low.

She was put on oxygen and admitted for an echocardiogram that didn’t reveal any problems with her heart, Faucheux said.

“The testing began,” she said.

Kaydence stayed at Children’s Hospital for the month of June, while doctors searched for answers.

Cystic fibrosis, heart disease, whooping cough and a severe milk allergy that affects the lungs were all suspected and ruled out, Faucheux said.

The next step was surgery for a lung biopsy.

“That was a hard decision,” Faucheux said. “We had no other choice.”

Armed with lung biopsy results and a genetic test for Kaydence, a pathologist in New Orleans first suspected surfactant protein C deficiency, Faucheux said.

The family was referred to Texas Children’s Hospital, where Vece was able to make the final, formal diagnosis.

In her own research, Faucheux had come across the lung disease, but still, when the family got the diagnosis, “I was so caught off guard,” she said.

She learned there was no cure and that Kaydence would one day require a double-lung transplant.

Kaydence’s condition is one of a group of rare disorders called children’s interstitial lung disease (chILD). Interstitial refers to a small area or space in an organ or tissue.

“It is not one disease but a group of rare disorders,” reads an educational booklet for families, created by the Children’s Interstitial Lung Disease Foundation.

“Only in the recent past have doctors agreed on how to define and diagnose chILD,” the booklet said. “There is not yet an organized reporting system. That’s why it’s hard to know how many children have chILD and what their futures hold.”

Kaydence’s form of chILD is one of genetic abnormalities of surfactant.

For “about 50 percent of the cases, it’s a brand new (genetic) mutation,” Vece said of the protein C deficiency.

That’s the case for Kaydence, whose parents don’t carry the genetic trait for the disease.

Their three other children, daughters Justice, 14, and Lyric, 6, and son Lionell Jr., 11, are free of the disease.

Vece said he treats five patients with surfactant protein C deficiency, who live in the Houston area, but also serves as a second consult for several children out of state, such as Kaydence, because the condition is so seldom seen.

Kaydence’s doctor in New Orleans is Dr. Dean Edell, director of the Pediatric Pulmonary Division of Children’s Hospital.

Texas Children’s Hospital is part of a network of other medical centers and hospitals in the U.S. called the Children’s Interstitial Lung Disease Research Network.

The network’s goal is to develop a national database “with the ultimate goal of developing therapies for these rare diseases,” said Vece, who is also an assistant professor of pediatrics at Baylor College of Medicine.

Now, though, because of her lung condition, Kaydence doesn’t leave the house except for doctor visits.

Kaydence is admitted to Children’s Hospital for three days every month for one of her medicines that is delivered intravenously, her mother said.

The family also takes her every couple of months to Texas Children’s Hospital for checkups and will be going next in late March.

Family members help with the other children when those doctor visits come up or when Faucheux needs to run errands.

Faucheux has found support, through the Internet, from other parents of children with surfactant protein C deficiency.

“It’s nice to talk to parents who are going through the same thing,” Faucheux said.

“She’s at a fun age right now ... she’s really spoiled,” Faucheux said of her youngest daughter.

Faucheux and her husband created a Facebook page for Kaydence, called “Prayers for Kaydence.”

The heart-warming pictures of Kaydence on the page were taken by Kaydence’s dad, since the little girl can’t be taken out to a photo studio.

Developmentally, Kaydence is doing fine. She’s rolling over and starting to crawl, her mother said.

“She never used to smile,” Faucheux said of her little girl.

But, she said, “she has been so much happier in the last couple of months,” Faucheux said. “She’s feeling better. She’s a happier baby.”