Median arcuate ligament syndrome: challenges, comorbidities, and controversies

Median arcuate ligament syndrome (MALS) is understood to be a condition where compression of the celiac artery by the median arcuate ligament (MAL) may lead to symptoms of postprandial or exercise-induced abdominal pain, nausea, vomiting, diarrhea, oral aversion, and weight loss. This review summarizes recent literature on pediatric MALS while highlighting the challenges, comorbidities, and controversies encountered in this condition.

The pathophysiologic mechanism by which MALS leads to pain is currently unknown. Several overlapping conditions are described in MALS, including mental health comorbidities to autonomic disorders such as orthostatic intolerance, POTS, or Ehlers-Danlos syndrome. Comorbid gastrointestinal conditions may include gastroesophageal reflux disease (GERD), inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and gastroparesis. This overlap makes it difficult to distinguish the cause of broad symptoms patients may experience. MALS remains a complex and controversial topic with particular challenges in consensus diagnostic criteria, normative values in children, symptom definition or correlation, patient selection, predictive outcomes, or long-term follow-up data.

Patients with MALS deserve a comprehensive multidisciplinary team to address their health. There is also a desperate need for collaborative research including randomized control trials in adults and a multicenter patient registry.