Meet Our Providers

Caroll Koscheski, MD, FACG

Dr. Koscheski has been in practice in Hickory since 1991. He received his undergraduate degree from the University of Oklahoma. Dr. Koscheski received his medical degree from Louisiana State University, where he completed his residency and fellowship. He is board certified in gastroenterology and is a Fellow of the American College of Gastroenterology. He has served as Chief of Staff at Frye Regional Medical Center in Hickory. Dr. Koscheski completed two terms for the American College of Gastroenterology (ACG) as Governor for the State of North Carolina. Recently, he received the American College of Gastroenterology William D. Carey Award in honor of his years of distinguished service to the Board and the College, including leadership positions, participation in educational efforts and committee service. Dr. Koscheski has also been selected by his peers to the “Best Doctors in North Carolina” list.

John Meier, MD, FACG

Dr. Meier joined in practice with Dr. Koscheski in 1994. A native of Atlanta, Dr. Meier received his undergraduate degree from Duke University and his medical degree from the Medical College of Georgia. He completed his residency and fellowship at Fitzsimons Army Medical Center in Aurora, Colorado. He is board certified in gastroenterology and is a Fellow of the American College of Gastroenterology. Dr. Meier has been selected by his peers to the “Best Doctors in North Carolina” list. He also received the Patients’ Choice Award presented by Vitals.com in recognition of the difference he has made in the lives of his patients, an honor given to physicians who received near perfect scores as voted by their patients.

Simon Allport, MD

Dr. Allport joined Gastroenterology Associates in 1999. A native of England, he received his undergraduate and medical degrees from the University of London. He completed his residency at Good Samaritan Medical Center in Phoenix, Arizona, and his fellowship at Emory University School of Medicine in Atlanta. He is board certified in gastroenterology. Dr. Allport has been selected by his peers to the “Best Doctors in North Carolina” list. He also received the Patients’ Choice Award presented by Vitals.com in recognition of the difference he has made in the lives of his patients, an honor given to physicians who received near perfect scores as voted by their patients.

Gaa Richardson, MD

Dr. Richardson joined Gastroenterology Associates in 2008. Following undergraduate training at New York University and Louisiana State University, she received her medical degree from the University of Alabama in Birmingham. Dr. Richardson completed her residency and fellowship at Saint Louis University in St. Louis, Missouri. She is board certified in gastroenterology.

Susan Nikrooz, MD

Dr. Nikrooz joined Gastroenterology Associates in 2009. She is a native of Lincolnton, NC. She received her undergraduate degree from the University of North Carolina at Chapel Hill. She received her medical degree from East Carolina University Brody School of Medicine. Dr. Nikrooz completed her residency in internal medicine and fellowship in gastroenterology at Virginia Commonwealth University. She is board certified in gastroenterology. Dr. Nikrooz has been selected by her peers to the “Castle Connolly Top Doctors Central Carolina” list. She also received the Patients’ Choice Award presented by Vitals.com in recognition of the difference she has made in the lives of her patients, an honor given to physicians who received near perfect scores as voted by their patients.

Kristen Mussari, MD

Dr. Mussari joined Gastroenterology Associates in August 2019. Dr. Mussari is a native of Pennsylvania where she completed her medical training. She earned her undergraduate degree from the University of Pittsburgh. She received her medical degree from Geisinger Commonwealth School of Medicine in Scranton. After completing an internship and residency at Penn State Health Milton S. Hershey Medical Center in Hershey, Dr. Mussari went on to complete a fellowship in gastroenterology at Allegheny Health Network in Pittsburgh. Dr. Mussari is board certified in gastroenterology.

Disha Shah, DO

Dr. Shah joined Gastroenterology Associates in August 2021. She is a native of New York. Dr. Shah earned her undergraduate degree in biology and chemistry from Rosemont College in Bryn Mawr, Pennsylvania, and received her medical degree from New York Institute of Technology College of Osteopathic Medicine. Dr. Shah served as Chief Resident at New York- Presbyterian Queens where she also completed her fellowship in gastroenterology. Dr. Shah is board certified in gastroenterology.

Bradley Zins, MD

Dr. Zins joined Gastroenterology Associates in May 2022. He brings more than 25 years of experience to the practice as gastroenterologist at the Billings Clinic, the largest multi-specialty physician group in Montana. Dr. Zins earned his undergraduate degree from the University of Michigan in Ann Arbor and received his medical degree from Wayne State University School of Medicine in Detroit. He completed his residency and fellowship at the Mayo Clinic School of Graduate Medical Education in Rochester, Minnesota. Dr. Zins is board certified in gastroenterology.

Behnam Laderian, MD

Dr. Laderian joined Gastroenterology Associates in September 2023. Dr. Laderian earned his undergraduate degree in biochemistry from the University of Nebraska-Lincoln and received his medical degree from the University of Nebraska Medical Center in Omaha. Following an internship and residency at the University of Iowa Hospitals & Clinics in Iowa City, Iowa, he went on to complete fellowship training at Tulane Medical Center in New Orleans. Dr. Laderian is board certified in gastroenterology.

Justin Ellis, PA-C

Justin joined Gastroenterology Associates in 2015 and brings more than fifteen years experience as a physician assistant to the practice. He grew up in Statesville, NC. He received his undergraduate degree in biology from Campbell University in Buies Creek. He completed his physician assistant program at Mountain State University in Beckley, West Virginia. Justin is board certified by the National Commission on Certification of Physician Assistants and licensed in the state of North Carolina. Justin is certified in Basic Life Support (BLS) and Advanced Cardiac Life Support (ACLS).

Diane Scaife, ANP-BC

Diane joined Gastroenterology Associates in August 2016 as a licensed adult certified nurse practitioner. Prior to joining Gastroenterology Associates, Diane gained extensive experience as a certified nurse practitioner with gastroenterology practices in Shelby, NC and Toledo, Ohio. She began her career as a registered nurse at Mercy St. Vincent Medical Center in Toledo, Ohio, working in critical care, then later served there as a certified nurse practitioner for trauma patients. She is a graduate of the University of Toledo College of Nursing, where she also earned a Master of Science degree in nursing. A member of the American Academy of Nurse Practitioners, Diane is certified in Basic Life Support (BLS) and Advanced Cardiac Life Support (ACLS), and a two-time recipient of Nursing Excellence Awards for Patient Care.

Kristie Ennis, PA-C

Kristie joined Gastroenterology Associates in August 2018. She brings more than ten years of experience as a gastroenterology physician assistant to the practice. Previously, she was a physician assistant with a gastroenterology practice in the Charlotte region caring for patients at four hospitals. Kristie also served as a medical assistant with an internal medicine practice in Statesville. Kristie is board certified by the National Commission on Certification of Physician Assistants and licensed in the state of North Carolina. She is a member of the American Academy of Physician Assistants and Certified in Basic Life Support (BLS) and Advanced Cardiac Life Support (ACLS). Kristie earned her undergraduate degree in biology from Elon University and a Master of Medical Science Physician Assistant degree from Wake Forest University.

Mayla Chung, PA-C

Mayla joined Gastroenterology Associates in March 2021. She earned her undergraduate degree in biology from the University of North Carolina at Chapel Hill where she worked as a research assistant. She received a master’s degree in physiology from NC State University and her master’s degree in Physician Assistant Studies from Wingate University. Prior to joining Gastroenterology Associates, she served as an ophthalmic technician, pharmacy technician, and biochemistry teaching assistant. Mayla is board certified by the National Commission on Certification of Physician Assistants and licensed in the state of North Carolina. She is a member of the North Carolina Academy of Physician Assistants and the American Academy of Physician Assistants. Mayla is certified in Basic Life Support (BLS) and Advanced Cardiac Life Support (ACLS).

Alicia Paxson, PA-C

Alicia joined Gastroenterology Associates in April 2021. She earned her undergraduate degree from the University of North Florida. She received her Master of Health Science–Physician Assistant degree from the University of South Alabama. Most recently, Alicia served as physician assistant in transplant cardiology and advanced GI surgery with Tampa General Medical Group at Tampa General Hospital Transplant Institute. Prior to that, she was a physician assistant in colorectal surgery with Tampa General Hospital-University of South Florida. Additional physician assistant experience includes work in cardiothoracic surgery, clinical cardiology, family practice and emergency medicine. Alicia is board certified by the National Commission on Certification of Physician Assistants and licensed in the state of North Carolina. She is a member of the American Academy of Physician Assistants. Alicia is certified in Basic Life Support (BLS) and Advanced Cardiac Life Support (ACLS).

Michelle Sain, FNP-C

Michelle joined Gastroenterology Associates in September 2023. She earned her undergraduate degree in nursing from Louisiana College in Pineville, Louisiana. She completed her Master of Science degree specializing in the family health nurse practitioner program at Southern University and A&M College in Baton Rouge. Michelle began her career as a registered nurse, then later served as nurse practitioner with the North Carolina Department of Adult Corrections and Appalachian State University. Michelle is board certified by the American Academy of Nurse Practitioners. She is certified in Basic Life Support (BLS) and Advanced Cardiac Life Support (ACLS). Michelle is a member of the American College of Gastroenterology.