Seeking a Fighting Chance for Cystic Fibrosis Patients
Taking time off between college and medical school, Dr. Pittman applied to be Dylan’s nanny. “During our interview, his mom started talking about Dylan’s cystic fibrosis (CF), assuming that, because I majored in biology and planned to go to medical school, I knew about the disease. But, I had to go look it up after we hung up.”
Dr. Pittman quickly learned the grim realities of the most common life-limiting genetic disorder in Caucasians in the United States. Its hallmarks are chronic malabsorption of nutrients and progressive lung disease. Children with CF are usually diagnosed in infancy because the inability of their pancreatic enzymes to absorb nutrients causes a failure to thrive. But the reason why 50 percent of CF patients don’t make it into their 30s is that progressive airway damage caused by thick mucus harbors bacteria, setting the stage for infections.
Being Dylan’s nanny opened Dr. Pittman’s eyes to the challenges families of CF patients face. Children with CF must take pancreatic enzyme supplements with every meal their entire lives. These supplements, plus the medicine taken to keep acid reflux at bay, add up to as many as 40 pills a day. They must undergo 30-minute, twice-daily sessions of chest physiotherapy involving a vest they strap on to shake up the mucus in their lungs, as well as inhale antibiotics three times a day to ward off infection. Even with that burdening regimen, and for reasons not fully understood, many children with CF enter their teenage years with lung function so diminished transplantation is the only hope.
The experience caring for Dylan set Dr. Pittman on the path to become a pediatric lung specialist determined to not only treat children with cystic fibrosis but, through research, to find ways to minimize, if not prevent, their progressive lung disease. Today, thanks to a grant from the Children’s Discovery Institute (CDI), she is doing just that by studying the effects of pulmonary exacerbation, or flare ups of lung infection and inflammation, on the long-term health and prognosis of CF patients. These exacerbations are treatable through antibiotics. The problem is that, each time one occurs, the lungs have a harder and harder time bouncing back, and some kids are harder hit than others.
“I would argue that, while we’ve been treating the downstream effects of worsening lung function, that treatment isn’t doing enough to halt the progression of lung disease,” Dr. Pittman says. “Before we can do that, we need more understanding around the origins of that disease.”
Through her CDI-funded research, Dr. Pittman plans to follow a small group of CF patients with CF.
“CDI funding has enabled me to tap into technology unique to us at St. Louis Children’s Hospital and the School of Medicineand just a few other medical centers to conduct this pilot study,” Dr. Pittman says. “With it, I’m confident I will be able to gather the data needed to justify a larger multi-center study grant. My goal is to make a lasting impact on the lives of CF patients everywhere.”
When the patients in the study group experience exacerbations, she will test their lung function during treatment, after symptoms have abated and two to three months out. In addition to measuring lung function at these key points, Dr. Pittman will take advantage of the School of Medicine’s wealth of DNA sequencing resources to discover the common microbes that live inside the lungs of the study participants. Her plan is to follow them for a year or more to develop an understanding of how a CF patient’s bacterial community changes during and after exacerbations. How do the antibiotics currently used change the microbial communities and the structure of the lungs? Can that knowledge be used to predict the likelihood of the next exacerbation and create more timely, effective and predictable interventions?
As director of the St. Louis Children’s Hospital Pulmonary Function Lab, Dr. Pittman sees first-hand the unpredictable, uneven and heartbreaking nature of CF, as illustrated by two of her 13-year-old female patients.
“Both are lovely girls with very supportive families, who are fully compliant with their prescribed treatment.”
Patient 1 takes 34 pills a day, undergoes five 20-minute breathing treatments a day and does chest physiotherapy 30 minutes at least twice a day. She hasn’t been hospitalized in more than four years and is maintaining excellent lung function.
Patient 2 also does everything by the book. She takes the same number of pills as Patient 1, but must undergo eight inhaled therapies a day, chest physiotherapy three to four times a day, and she receives bi-weekly injections aimed at her allergies. She was hospitalized six times in 2015. When she was about 9- or 10-years old, an intestinal blockage – a common complication of CF – required intensive care hospitalization for many weeks, during which time she suffered a stroke. Along the way, she picked up a chronic lung infection that may make it more challenging for her to have good outcomes after a lung transplant. Her lung function currently sits at around 50 percent.
“What drives me in my research is this dichotomy of what makes one patient respond in one way and one to respond differently to the same treatment,” Dr. Pittman says. “I want to be able to give my patients hope that if they stay true to the treatment prescribed, they will be able to graduate from college, get married, have children and dance at their weddings.”