Out of the approximately 4 million live births in the United States each year, 800 babies are born with a life-threatening condition called Hirschsprung’s Disease (HD). The condition is a birth defect. But there is no currently available way to test for it prenatally.
“Babies born with Hirschsprung’s Disease are typically missing a specific type of nerve cells, called ganglion cells, in their colon (large intestine) and rectum,” explains Dr. Miguel Saps of the University of Miami Health System, who is an international expert in the disease. “Their bodies are unable to pass a stool easily.”
Dr. Saps serves as UHealth’s George E. Batchelor Chair in Pediatrics, and Chief of the Division of Pediatric Gastroenterology, Hepatology and Nutrition at the Mailman Center for Child Development. The Center houses one of the top 10 programs in the United States for children with neurodevelopmental disabilities and chronic illness.
“Some children born with HD also are missing these cells in the small intestine,” he adds. “This can put them at risk for serious bowel blockages.”
Diagnosing and Treating
According to Dr. Saps, the disease is more common in boys than girls, but doctors do not yet know why. While 90 percent of cases are diagnosed and treated in the first year of life, some individuals do not showcase symptoms until childhood.
Doctors typically become aware of the disease when they notice the following symptoms:
- The inability of the baby to have a bowel movement within the first two days following birth.
- Swollen stomach/belly area
- Constipation and/or diarrhea in the first few months of life
“There is a higher risk for the disease among children born with Down syndrome, congenital heart defects, and other medical issues,” he adds. “This is related to Hirschsprung’s disease being caused by a genetic abnormality.”
The first line of treatment, he says, is surgery to either remove the non-functioning part of the baby’s colon or to bypass that section completely.
Research Needed to Improve Outcomes
Because the disease affects so few children, it is known as an orphan disease — the type of disease that is researched and funded far less often than conditions impacting thousands or millions of children annually. Yet research is needed and underway, says Dr. Saps. Clinicians and scientists seek to learn why some babies are born with the condition and others are not. Additionally, he says, surgical results are not universally successful worldwide.
“Early diagnosis is important to optimal results,” says Dr. Saps, “but we still must determine what else happens in children with this disease. We can fix the ‘mechanical’ part of the condition — allowing the body to pass stools in an alternate way. Yet in many cases, there are associated immune dysfunctions in the colon that may result in inflammation (called enterocolitis) with negative effects.”
One study, coordinated by the Children’s Hospital of Eastern Ontario, researched 107 children treated for HD over the time of 22 years. The authors reported that only 64 percent of treated patients were interpreted as having “normal” stooling habits.
Following surgery, says Dr. Saps, the disease can cast a negative shadow for the child, as a large proportion continue to have problems with their stools even if the surgery was appropriately done. These children may later need a specialist that deals with the movement of the intestines.
Creating a New Model for Lifelong Care
There are currently 16 clinical research studies underway worldwide focused on HD. Some of the most promising, says Dr. Saps, are studying the potential of using stem cells to create the missing nerve cells in children with the disease.
UHealth’s research team is one of the few centers anywhere studying intestinal and anorectal motility disorders—abnormal intestinal contractions and anal sphincter relaxation—after surgery for HD. By looking at both sides of the disease, Dr. Saps says answers will eventually be found — leading to new ways to prevent and treat Hirschsprung’s Disease.
More immediately, he believes that a greatly improved focus on comprehensive and follow-up care is essential to helping children. The new colorectal center just established at UHealth is helping to lead the way on that front.
“We are helping to establish a standard of care for adolescents and adults who were treated for HD in infancy,” he says. “Until now, it was completely missing from the medical guidelines, how to transition a patient to the right type of care and support as he or she ages. As clinician-researchers here at UHealth, we are privileged to be in a place where our mission can multiply the impact of our work for patients everywhere.”
John Senall is a contributing writer for UMiami Health News.