Caring for kids with MALS: It’s not all in their head

The medical journey of children with median arcuate ligament syndrome (MALS) is a long and arduous one, replete with exhaustive medical tests, misdiagnoses, and multiple encounters with pediatricians and subspecialists who often attribute a youngster’s chronic abdominal pain to stress or depression.

“Anorexia is a common misdiagnosis because children lose weight when they can’t eat without pain. We’ve also seen children with MALS who were diagnosed with medical child abuse,” said Christopher Skelly, MD, Medical Director of the Noninvasive Vascular Lab at UChicago Medicine.

Comer Children’s Hospital has one of the few multidisciplinary teams in the country specializing in diagnosing and treating MALS, a vascular compression syndrome that occurs when the celiac artery is compressed by the median arcuate ligament. The team is comprised of Surgeon-in-Chief Grace Mak, MD, vascular surgeon Skelly, pediatric psychologist Tina Drossos, PhD, an interventional radiologist and a pain specialist. Skelly and Mak first performed pediatric laparoscopic MALS surgery in 2008. Today, Comer treats close to 100 children with MALS each year.

A Multifaceted Approach

Many pediatricians and some pediatric gastroenterologists have never heard of MALS, so it’s not surprising that patients arrive at Comer with an extensive medical record detailing months or years of postprandial epigastric pain, nausea, diarrhea, and weight loss.

According to focus groups conducted with Comer patients and their parents, children with MALS prior to diagnosis averaged eight visits to their primary care providers, six visits to medical specialists, six trips to the ED, and saw the school nurse 30 times – in one year.

“It was really hard for me to be sick for so many years and have all of my doctors telling me that the pain was in my head, that I was making it up, that I was seeking attention,” said one patient. One parent described feeling helpless at her inability to reassure her child without having a diagnosis. “My daughter…had the fear that she was going to die. ‘What is this? It won’t go away. I’m getting no relief. I’m going to die.’ And truthfully, I couldn’t tell her that she wasn’t,” she said.

Estimating the prevalence of MALS is challenging since many people face barriers to diagnosis and treatment. “We estimate that 3% to 33% of the population has compression of the celiac artery, affecting upwards of 10 million children,” said Skelly.

Some children are asymptomatic. Others have the compression but the source of their chronic abdominal pain is due to another disorder. Children in these two subgroups don’t need MALS surgery.

At Comer Children’s, the MALS team evaluates children for potential surgery. MALS is a diagnosis of exclusion, so patients first undergo a multipart diagnostic process involving radiologic studies and an extensive gastrointestinal workup, including duplex ultrasound and computed tomography angiogram to rule out other causes of chronic abdominal pain.

“Our multidisciplinary program allows us to identify those patients whose pain is most likely caused by the compression and who will benefit from surgery,” said Mak. “We also want to ensure that patients who are candidates for surgery have optimal outcomes, so we require all patients to have a pre-surgical psychological assessment.”

About half of pediatric patients with symptomatic MALS have at least one co-morbid psychiatric disorder, including depression and/or anxiety. In some cases, a child’s struggles with MALS symptoms and a lack of diagnosis may cause the psychiatric disorder.

“My primary care physician thought that it was depression,” said one patient about her pre-Comer medical experiences. “I was definitely depressed, but that wasn’t what was causing the problem. The doctors didn’t believe me when I said that I was perfectly fine before the pain started.”

For other children, MALS may exacerbate preexisting psychiatric problems. Yet there is no evidence to suggest that MALS surgery alone will mitigate psychiatric symptoms.

“If mental health problems are not addressed, at least half of these kids will continue to have psychiatric conditions following surgery that successfully relieves their pain,” said Drossos, who has published research with Skelly and Mak on the psychological factors and outcomes in children with MALS.

“Unresolved mental health issues can be just as debilitating and impactful on a child’s overall well-being as an anatomical anomaly that causes stomach pain,” she said.

Comorbid psychiatric problems can also lead to suboptimal surgical outcomes. “Mental health problems can affect children’s physical recovery from surgery and can cause continuing stomach pain despite a successful surgical outcome,” said Drossos.

Importantly, a comprehensive psychological assessment -- in-person for local patients and via Zoom for children living out of state or internationally -- can also help determine if a child’s symptoms are the result of a psychiatric disorder rather than MALS.

Many of our patients are so grateful to have finally found providers who listen to them and believe their chronic abdominal pain is caused by a physical anomaly rather than a psychiatric problem.

After reviewing each child’s medical and psychological findings, the MALS team determines whether surgery and a presurgical mental health intervention are warranted.

“Most of the time we recommend individual cognitive behavioral therapy, which can be done at Comer or elsewhere. But we might also refer a child to a pain management program to learn coping skills related to pain,” said Drossos.

Children are followed for a year post-surgery, a period where they will often continue mental health therapy. Kids may be anxious that their symptoms will return or their eating habits will be affected.

“It can be challenging to begin eating normally again after months or even years of restricting food to avoid pain,” said Drossos. “The behavior persists even though they no longer have postprandial pain.” These children may be referred to Comer’s eating disorders program.

A Tandem Approach to Laparoscopic Surgery

Surgery to release the median arcuate ligament in children is nearly always performed laparoscopically at Comer, and jointly by Mak and Skelly, a unique pairing of surgeons.

Mak has expertise in pediatric surgery and laparoscopic procedures while Skelly has the extensive training and experience to excise tissue on the surface of the celiac artery and the aorta to ensure a good release.

He also ensures that the compression is completely released by performing an intraoperative mesenteric duplex ultrasound.

“Many surgeons at other centers skip this step, but duplex allows us to see if there is any remaining compression that we need to alleviate,” said Mak.

“And as part of our surgery, we always perform a neurolysis by dividing the nerves in that area. We have found that the addition of these two steps results in an improvement in our patients’ pain, which is likely due to a combination of the vascular compression and nerve irritation in that area.”

For 70% to 80% of children with MALS, surgically releasing the median arcuate ligament with neurolysis results in diminished abdominal pain and improved quality of life. But about one-third of patients have persistent or recurrent abdominal pain. A second surgery may be warranted if the duplex ultrasound reveals the presence of scar tissue.

“We can do an angioplasty to help the artery remodel,” said Skelly. “Or, for some patients, a pain specialist will perform a celiac plexus block to temporarily deaden the nerves.”

Patients also use the coping strategies they’ve developed during cognitive behavioral therapy for pain management.

Regional and national referrals to Comer’s MALS program have increased over the last few years, indicating the growing awareness of pediatricians and pediatric gastroenterologists of the disorder. But more educational outreach is needed.

“We are actively involved with the MALS Foundation, a nonprofit started by several of our patients and parents of patients, to increase awareness and education of patients and providers about MALS,” Skelly said. “Chronic abdominal pain is devastating for kids. If surgery can resolve their pain, it can change the trajectory of their lives.”

Added Mak: “Many of our patients are so grateful to have finally found providers who listen to them and believe their chronic abdominal pain is caused by a physical anomaly rather than a psychiatric problem.”