2 Years of Service with AGA

Medical Offices

Endoscopy Centers


Special Services


Dr. Castresana is an honors graduate of the Georgia Institute of Technology where he received a bachelor’s degree in industrial engineering. After completing a master’s degree in manufacturing management from Pennsylvania State University’s College of Business and Engineering, he received a medical degree from the Medical College of Georgia in Augusta.

He completed his residency at the University of Miami Miller School of Medicine /Jackson Memorial Health Systems, and a fellowship in gastroenterology and hepatology at the University of New Mexico School of Medicine in Albuquerque.  While serving as an assistant professor there, he completed a second fellowship in advanced endoscopy and received the Distinguished Young Faculty Award. Most recently, he served as an assistant professor of gastroenterology and advanced therapeutic endoscopy at Oregon Health Sciences University in Portland.

Dr. Castresana has been widely published in peer-reviewed journals, including Digestive Diseases and Sciences, Gastrointestinal Endoscopy, and the Journal of Gastroenterology, Hepatology and Endoscopy.

In addition to general gastroenterology, he specializes in the diagnosis and treatment of pancreaticobiliary diseases such pancreatic and bile duct cancers, bile duct stone disease, acute and chronic pancreatitis, pancreatic cysts, and inflammatory pancreatic fluid collections (pseudocysts and walled off necrosis). He is specially trained in advanced therapeutic procedures, such as endoscopic ultrasound (EUS) and ERCP.

Dr. Castresana is fluent in Spanish and joined Atlanta Gastroenterology Associates in 2020.

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