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Updated: September 19, 2023

Northern Light Mercy Hospital expands team of gastroenterology specialists

Northern Light Mercy Hospital in Portland has added two physicians and a nurse practitioner to the Northern Light Mercy Gastroenterology team.

The three providers join a team of board-certified specialists that diagnose and treat digestive disorders such as gastroesophageal reflux disease (GERD), Crohn’s disease, irritable bowel syndrome (IBS) and pancreatitis, as well as provide screenings for colorectal cancer and polyp removal.

Courtesy / Northern Light Mercy Hospital
Aloysius Rho

Aloysius Rho is a gastroenterologist with over 20 years of experience. He specializes in diagnosing and treating colon cancer, GERD, IBS, Barrett’s esophagus, peptic ulcer disease, and liver cirrhosis, in addition to being proficient in procedures such as endoscopy, colonoscopy and polypectomy.

Prior to joining Mercy Hospital, he served as a clinical instructor of medicine at University Hospital, the principal teaching hospital of Rutgers University in Newark, N.J. He was also an attending physician in the Department of Gastroenterology at Penn Medicine Princeton Medical Center in New Jersey.

Rho attended medical school at SUNY Health Science Center in Brooklyn, N.Y., after completing his undergraduate studies at Wesleyan University in Middletown, Conn. He completed his internal medicine residency at Beth Israel Medical Center in New York before being fellowship-trained in gastroenterology at Rhode Island Hospital, the teaching hospital of the Warren Alpert Medical School of Brown University.

Rho is a member of several professional organizations, including the American College of Physicians, the American College of Gastroenterology and the American Gastroenterological Association.

Courtesy / Northern Light Mercy Hospital
Sarah Southard

Sarah Southard is an adult nurse practitioner experienced in colorectal, thoracic and vascular surgery.

She received her master of science degree in adult primary care nursing from Simmons College in Boston. She also completed extensive research on inpatient ostomy pathways to reduce the readmission of patients with colorectal cancer.

Prior to joining Mercy Hospital, Southard worked in thoracic surgery at Maine Medical Center after serving for over 13 years in vascular and colorectal surgery departments at Beth Israel Deaconess Medical Center in Boston.

Outside of work, she enjoys volunteering in her community and long-distance running, having completed six Boston Marathons. She is an active member of the Maine Responds Volunteer Registry, the Catherine Morrill Day Nursery and the Foundation for Portland Public Schools.

Andrew Hsu has extensive training in gastroenterology, advanced endoscopy and internal medicine. 

Courtesy / Northern Light Mercy Hospital
Andrew Hsu

He received his medical degree from New York University School of Medicine after earning a biochemistry and molecular biology bachelor’s degree from Brown University.

He completed his internal medicine residency at the University of Massachusetts Medical School before being fellowship-trained in advanced endoscopy and gastroenterology at Dartmouth Hitchcock Medical Center in New Hampshire and the John H. Stroger Jr. Hospital of Cook County in Chicago.

Northern Light Mercy Hospital is ranked No. 6 among the state's largest hospitals, according to the 2023 Mainebiz Book of Lists, based on a licensed bed count of 200. The hospital has 1,470 employees and reported $579 million in revenue during 2020, the most recent year data was available.

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