Median arcuate ligamentum syndrome: Four case reports

BACKGROUND: Median arcuate ligamentum syndrome (MALS) is a disease entity with unclear pathogenesis. If it is not considered in advance, the clinical diagnosis of the disease is very difficult because patients complain of digestive discomfort including pain. However, this characteristic is not specific to MALS. There have been no studies to assist in making a quick diagnosis. The aim of this case series was to recognize that MALS must be considered as a differential factor in the cause of abdominal pain. CASE SUMMARY: We described cases in which four patients complained of abdominal pain over a long period but in whom a diagnosis of MALS could not be made. If the gastroenterologist does not take into account abdominal pain in advance, the patient is considered an asymptomatic gallstone patient and has their gallbladder removed despite imaging evaluation. The patient may also be considered a psychiatric patient and may be administered psychiatric drugs over a long period. In all four cases in this report, the patients experienced abdominal pain. In three cases, the diagnosis was possible by the clinician’s judgment considering both clinical symptoms and imaging techniques shortly after the onset of symptoms. However, in one case that lasted over 20 years, a clear diagnosis was not possible. Even after complaining of colicky pain and performing a cholecystectomy, the diagnosis was made only after the symptoms persisted. In all four cases, the symptoms were relieved by neuromodulators. CONCLUSION: MALS is a rare disease and it is easy to miss because it is not malignant, but patients can suffer from pain over a long period. For the accurate diagnosis of a patient complaining of abdominal pain, the diagnosis must be differentiated. In addition, as there are asymptomatic patients, patients who need treatment should be carefully selected, and improvement with medical treatment can be expected. Large-scale studies are also needed.