Gallstone migration as a cause of acute pancreatitis

The discovery that the transient blockage of the ampulla of Vater by spontaneous gallstone migration into the duodenum is fascinating, not because of its complexity - which is quite simple - but of the ability to connect a surgical finding with the pathophysiology of pancreatitis. In early 1971, while operating on a patient with an acute abdomen, he found the patient had pancreatitis. After opening the duodenum, he observed a gallstone in the duodenal lumen, which looked like the gallstones this patient had in the gallbladder. This finding intrigued him and reminded him of a paper published by Opie in 1901⁵. Opie had suggested for the first time that gallstones impacted at the terminal bile duct could block the bile and pancreatic ducts and cause acute pancreatitis⁵. However, over the next 50 to 60 years, the investigators were unable to find any impacted stone at the terminal bile duct in patients who had died of acute pancreatitis. Therefore, Opie’s initial observation was progressively left aside. During his stay in the United States, Dr. Acosta had conducted experiments occluding the sphincter of Oddi in laboratory animals and had observed that such blockage could generate an acute inflammatory process in the pancreas.

The incidental finding of a cholesterol stone that looked like the stones found in the gallbladder of the patient operated on in 1971 could now explain why there were no stones in the sphincter of patients with acute pancreatitis. Could it be possible that the stones, at least in most of these patients, were temporarily lodged in the sphincter and then passed into the duodenum? Thus, he hypothesized that acute pancreatitis is caused by “temporary” impaction of gallstones in the ampulla and, in addition, those gallstones spontaneously “migrated” into the duodenum. To test this hypothesis, he decided to examine the stools of patients admitted to the hospital with acute pancreatitis (abdominal pain, elevated amylase levels) during the first 10 days after hospitalization and compare the findings with a similar group of patients admitted with abdominal pain but without pancreatitis. For that purpose, during a daily round with the residents to follow inpatients’ progress, he asked who wanted to become famous working with stools. The resident Carlos Ledesma raised his hand and when the ward round ended Acosta took him to his office and gave him a metal strainer and a glass rod. Other professionals from the hospital and the environment made jokes and comments mocking this task. While this investigation was taking place, it became evident that the results definitively demonstrated that, a few days after the attack, there were gallstones in the stools of most patients with pancreatitis, but not in those without pancreatitis. This led to the publication of the most important paper on the pathogenesis of pancreatitis in the New England Journal of Medicine¹, the most renowned medical journal worldwide.

This discovery led to a series of studies that finally defined the “critical” period of time that a stone needed to be lodged blocking the bile and pancreatic ducts to damage the pancreatic tissue. Further studies eventually showed that those gallstones that were lodged in the ampulla of Vater for a few hours had minor significance. On the other hand, stones lodged in the ampulla for 48 hours caused significant and often lethal injury to the pancreas⁶. This understanding provides the basis for a radical change in the management of patients with acute pancreatitis: cholecystectomy and early sphincterotomy were an alternative to avoid the complications of pancreatitis. Later, sphincterotomy was found to be necessary only in the presence of an impacted stone. The advent of flexible endoscopes partly modified this management.

Surgery residency program

Soon after his return from the United States, Dr. Acosta took over the residency program at Hospital Escuela de Granadero Baigorria in the outskirts of Rosario, which was part of the School of Medicine. The residency program was a three-year, full-time program. Dr. Acosta imposed a discipline that required dedication, study, case presentations, registry of operations, complications, participation in scientific studies, etc.: in other words: it was a demanding, yet edifying program.

The hospital is surrounded by large grounds, and he was frequently organizing soccer games and playing with the residents just a few meters from the hospital. Meals and celebrations were also common with those of us, trainees, who always felt special loyalty to the “chief” and to the institution that allowed our professional growth. Undoubtedly, these were some of the best moments in the life of those of us who were trained by him, with a mixture of fear and satisfaction with our professional progress.

The professional life of this great master surgeon shows that determination, discipline and perseverance can overcome lack of resources. He always accepted criticism and did not shy away from questioning. He used to give a draft to some senior residents and asked us for our opinion. Once when one of us returned him the paper without any criticism, he said: “Hey, you didn’t read the paper. It can’t be possible that you have no comments to make.” He firmly believed that questioning our thoughts and behaviors would make us improve. This is how he could obtain information and decipher the cause and pathophysiology of acute biliary pancreatitis with very few resources at hand. His ideas and findings have helped to design new endoscopic and surgical treatments for a disease that had no solution until then. And to crown his efforts, he trained many surgeons who, in turn, have contributed to the education of new generations, making the saying: “a teacher affects eternity; he can never tell where his influence stops” come true.