Dr. Kestner graduated from the Thomas Jefferson University, Jefferson Medical College in 1968. He completed his internship at Philadelphia General Hospital in 1969, and his residency at Jefferson Hospital from 1969 – 1973. Dr. Kestner completed a pulmonology fellowship at George Washington University Medical Center in 1975.
Dr. Kestner specialized in Pulmonary Critical Care Medicine and Pulmonary Medicine, and was affiliated with Christiana Hospital. Dr. Kestner is certified in internal medicine and pulmonary disease, and was the president of the Academy of Medicine from 2006-2008.