In July, a team of experts from The Children’s Hospital of Philadelphia and the University of Pennsylvania published a case study in the journal Pediatrics describing an innovative, minimally invasive procedure that treated plastic bronchitis, a potentially life-threatening disease, in a 6-year-old boy with hypoplastic left heart syndrome (HLHS), a form of congenital heart disease in which the left side of the heart is severely underdeveloped. Using new lymphatic imaging tools and catheterization techniques, physician-researchers eliminated bronchial casts, which are an accumulation of lymphatic material that was clogging the child’s airway.
“Our technique represents a new treatment option for plastic bronchitis, which is a rare but often fatal complication of pediatric surgery for single ventricle disease,” says Yoav Dori, MD, PhD, a pediatric cardiologist in CHOP’s Cardiac Center, who is co-author of the study and part of a specialized team that includes interventional radiologist Maxim Itkin, MD, of the Perelman School of Medicine at the University of Pennsylvania, and Marc S. Keller, MD, an interventional radiologist at CHOP.
Plastic bronchitis is a lymphatic flow disorder, one of a group of diseases characterized by abnormal circulation of lymph. Some 5 to 10 percent of patients experience plastic bronchitis as a consequence of altered venous and lymphatic pressure resulting from the Fontan procedure, the last in the series of operations required to treat HLHS. The abnormal circulation causes lymph to ooze into a patient’s airway, where it congeals into a fibrous, caulk-like cast formation that takes the shape of the airway. If a child is unable to cough out the cast, the blockage may cause fatal asphyxiation. Existing medical treatments for plastic bronchitis can help relieve symptoms, but they are not curative, and patients may still require transplantation.
The study published in Pediatrics describes the case of a 6-year-old boy with HLHS who had undergone the Fontan procedure three years previously. At age five and a half, he suffered respiratory distress and was admitted to a local hospital in Texas, where he was diagnosed with plastic bronchitis. Over the next several months, despite a series of evaluations and drug treatments, he continued to have frequent casts.
The boy was referred to CHOP, where the care team used specially developed magnetic resonance imaging (MRI) to visualize the anatomy and flow pattern of lymph in his body, and pinpointed the leakage site: a network of dilated lymphatic vessels surrounding the airway and connected to the thoracic duct through a dilated lymphatic channel. Dori, Itkin and Keller performed the MRI lymphatic imaging techniques they have developed for these children, including dynamic contrast enhanced MR lymphangiography, which provides clear images of the anatomy and flow of the lymphatic system.
After analyzing the images, the team decided to use a technique called selective lymphatic embolization to treat the patient’s plastic bronchitis. Working in CHOP’s interventional cardiac catheterization suite, they injected iodized oil into the leaky small vessel lymphatic network surrounding the airway and then glued shut the abnormal dilated feeder lymphatic duct. Stemming the abnormal flow resolved the child’s plastic bronchitis. He was able to discontinue his respiratory medications, and, a year after the procedure, he remains asymptomatic. Although the limitations of the Fontan circulation persist, and continued medical management and surveillance are necessary, this innovative procedure proved to be lifesaving for this young boy.
The experience with selective lymphatic embolization for complications after the Fontan operation continues to grow. Its targeted, noninvasive application to only the affected site may offer better outcomes for patients. “It is becoming rapidly apparent that this technique may be the most effective means we have today for treating plastic bronchitis,” says Jack Rychik, MD, a co-author of the case study and director of CHOP’s Single Ventricle Survivorship Program.
He adds, “We now appreciate that the Fontan circulation affects many organ systems. Characterization of the lymphatic system and therapeutic lymphatic intervention will likely play an important role as we strive to better understand the overall circulatory consequences of the Fontan operation. A multidisciplinary approach involving teams of experts in single ventricle, cardiac catheterization and interventional radiology, all focused on the challenges these patients face, as witnessed in this report, is essential for the development of successful outcomes for these very fragile and unique patients.”
Dori Y, Keller MS, Rychik J, Itkin M. Successful treatment of plastic bronchitis by selective lymphatic embolization in a Fontan patient. Pediatrics. 2014 Jul 7. Epub ahead of print. Read the abstract.
CHOP and Penn launch Center for Lymphatic Imaging and Interventions
Building on their research and clinical expertise in lymphatic flow disorders, CHOP and Penn Medicine jointly launched the Center for Lymphatic Imaging and Interventions in September. Led by Dori and Itkin, the program provides highly specialized care for children and adults with lymphatic leaks and lymphatic flow disorders, including plastic bronchitis, chylothorax, chylopericardium, chylous ascites and other conditions. The clinicians on the Lymphatic Imaging and Intervention team have treated more than 300 adults and 50 children with lymphatic flow disorders, making the program the largest and most active of its kind in the world. For more information about the Center for Lymphatic Imaging and Interventions, call 215-590-2200 or email firstname.lastname@example.org.