Faculty - Crozer-Keystone Health System - PA


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

Associate Chair, Academic Affairs

Program 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. In October 2012 Dr. Rana was appointed a 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.

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 with hypertension and kidney disease, with an emphasis on prevention and treatment.

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

Joanne T. Connaughton, M.D., F.A.C.P.

Director, Ambulatory Care Internal Medicine Residency Program

Medical Director, Crozer Medical Associates

Dr. Joanne T. Connaughton earned her medical degree from the University of Massachusetts Medical School, Worcester, Mass. She completed a residency in internal medicine and service as chief resident at the University of Rochester, Rochester, NY. Dr. Connaughton is a member of the American College of Physicians, Society of General Internal Medicine and the American Geriatric Society.

Muhammad Tahseen, M.D.

Chief Resident

Dr. Muhammad Tahseen graduated from Allama Iqbal Medical College in Lahore, Pakistan and completed his Internal Medicine Residency at Crozer-Chester Medical Center. He joined the residency program as chief Resident and junior faculty. Dr. Tahseen is board-eligible by the American Board of Internal Medicine for Internal Medicine. Dr. Tahseen was the recipient of Intern of the Year ward. He takes a special interest in residents and medical students' education, their didactic activities and areas related to information technology.

Dr. Tahseen conducted many research projects and presented his work in various national and regional conferences. Management of diabetic ketoacidosis and The V- Project (Vancomycin dosing and monitoring its therapeutic levels in Adults) are examples of some of his recent work. He is also a co-author of a book chapter, “Use of ACEI and ARB in the management of the cardio-renal syndrome” with Dr. C. Nathan Okechukwu.

Ritu Khurana, M.D., F.A.C.P., F.A.C.R.

Dr. Ritu Khurana earned her undergraduate and medical degree in India. She completed her residency in internal medicine and a fellowship in rheumatology at Louisiana State University Health Science Center. She joins us from Temple University Hospital where she was an Assistant Professor of Medicine in the Department of Rheumatology.

In addition, Dr. Khurana is a member of the American College of Physicians, American College of Rheumatology and the International Society of Clinical Densitometry.

Alan Zweben, M.D.

Internal Medicine Associates

Dr. Alan Zweben received his medical degree from State University of New York at Stony Brook and completed his residency in Internal Medicine at Pennsylvania Hospital, Philadelphia. Dr. Zweben is certified in Internal Medicine by the American Board of Internal Medicine.

Dr. Zweben was voted a "Top Doctor" in 2011 in both Philadelphia Magazine and Main Line Today.

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