Faculty - Crozer-Keystone Health System - PA


Christine F. Giesa, D.O., FACOEP-D

Program Director, Transitional First Year Residency

Dr. Giesa received her medical degree from the Philadelphia College of Osteopathic Medicine in 1990. She completed an osteopathic internship at St. Joseph’s Hospital in Philadelphia in 1991. She completed her residency in emergency medicine at Albert Einstein Medical Center in 1994. She is board certified in emergency medicine by the American Osteopathic Board of Emergency Medicine.

Throughout her career, Dr. Giesa has been very involved with physician education. Following residency, she joined the department of emergency medicine at Albert Einstein Medical Center where she served as a clinical faculty member for the emergency medicine residency program until 2010. Dr. Giesa served as the Director of Osteopathic Medical Education for the Crozer-Keystone Health System and Program Director for the Osteopathic Traditional Rotating Internship at Delaware County Memorial Hospital from 2011 until 2017. She currently practices in the emergency department at Delaware County Memorial Hospital and has been there since 1994. Twice she has been the recipient of the “Outstanding Teaching Award” given by the Crozer-Keystone Family Medicine Residency Program.

Dr. Giesa is an active member of the American College of Osteopathic Emergency Physicians. She is a “distinguished” Fellow of the American College of Osteopathic Emergency Physicians. She has served as program director for both the Scientific Assembly and Spring Seminar educational programs. She is a national program speaker and also developed and presents the annual COLA Seminar. She is a member of the Board of Directors and is President of the American College of Osteopathic Emergency Physicians.

Ashish Rana, M.D., F.A.C.P.Ashish Rana, M.D., F.A.C.P.

Internal Medicine Residency Program Director

Senior Student Clerkship Director

Dr. Ashish Rana received his medical degree from the State University of New York-Stony Brook School of Medicine in 1992. Thereafter he completed his residency training at Thomas Jefferson University Hospital in 1995, after which he went on to practice medicine at the University of Pennsylvania-Presbyterian Medical Center campus for two years.

Dr. Rana joined the Crozer-Chester Medical Center in 1997 and began practice with Crozer Medical Associates. He is the Program Director and the course director of evidenced-based medicine and actively participates in residency and student teaching. He also serves as the site director for the fourth year medical student subinternship rotation in internal medicine at Crozer. In April 2000 he was inducted as a Fellow of the American College of Physicians. He was nominated for the Golden Apple Teaching Award by the students of the graduating class of 2000 at Allegheny University Medical School (now Drexel University College of Medicine). In May 2005 he was appointed Associate Professor of Medicine at Temple University.

Dr. Rana's particular interest is evidence-based medicine, including incorporation of these principles into everyday practice.

C. Nathan Okechukwu, M.D., F.A.S.N., F.R.C.S.C. Nathan Okechukwu, M.D., F.A.S.N., F.R.C.S.

Chairman, Department of Medicine

Dr. Nathan Okechukwu is a board-certified physician specializing in nephrology. Dr. Okechukwu received his medical degree from the University of Nigeria. He completed his residency at the University of Connecticut and his nephrology fellowship at the University of Michigan, Ann Arbor. He is a fellow of the Royal College of Surgeons of Edinborough, Scotland, and is board-certified in internal medicine and nephrology.

Dr. Okechukwu is committed to providing high-quality care for patients who have hypertension and kidney disease, with an emphasis on prevention and treatment.

In his spare time, Dr. Okechukwu enjoys writing novels, poetry, golf, chess and playting the guitar.

Stephen T. Higgins, M.D.Stephen T. Higgins, M.D.

Designated Instructional Officer

Director of Undergraduate Medical Education

Dr. Higgins received his medical degree from Hahnemann University Hospital, Philadelphia, PA. He completed his pediatric residency and neonatology fellowship at Thomas Jefferson University, Philadelphia, Pa. Dr. Higgins' areas of special interest include maternal fetal medicine, neonatology and neonatal intensive care. He serves as the chief of neonatology for Delaware County Memorial Hospital.

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