Ashley Giselle Fonseca-Mejia, MD

Dr. Fonseca-Mejia specializes in pediatric gastroenterology at Johns Hopkins All Children’s. She sees patients on the hospital’s St. Petersburg, Florida, campus. She joined the hospital staff in 2025.

She earned her medical degree from Universidad Central del Caribe in Bayamon, Puerto Rico. She completed a pediatrics residency at Nicklaus Children’s Hospital in Miami. She then completed a fellowship in pediatric gastroenterology at UT Southwestern Medical Center in Dallas. During her training, she completed translational research on patients with biliary atresia.

Her clinical interests include all aspects of general gastroenterology with special interests in inflammatory bowel disease, eosinophilic esophagitis and liver diseases. 

Dr. Fonseca-Mejia speaks English and Spanish.