Our Staff

Our Physicians & Staff

Leatrice Chang, M.D.
Leatrice Chang, M.D.

Attended Tufts University of Boston, graduated in 1979 and was board certified in Family Practice in 1982. She is on staff at Summit Medical Center of Oakland and John Muir Medical Center in Walnut Creek.

Gretchen Kunitz, M.D.
Gretchen Kunitz, M.D.

Attended the University of California San Francisco, graduated in 1980 and is board certified in Internal Medicine. Dr. Kunitz also completed a fellowship in primary care Internal Medicine. Prior to joining our practice, she worked as a community based internist in Berkeley, California. She then served as Medical Director of Quality at Alta Bates Summit Medical Center. In 2004 she completed a Health Care Leadership fellowship funded by the California Health Care foundation. She remains active in their alumni network. Several years ago she decided to return to part time clinical practice.

Mei Chow Kwan, M.D.
Mei Chow Kwan, M.D.

Graduated from University of Hong Kong in 1986, completed her residencies in affiliation with Johns Hopkins University and Tufts University. She is Board Certified in Internal Medicine, and is an Assistant Clinical Professor at UCSF. She's been in practice in Walnut Creek since 1994 and is on staff at John Muir Medical Center. Her breadth of practice involves Internal Medicine, Women's Health and common psychological issues. She like gardening, travelling and arts. She believes in active, balanced, positive living, regular health maintenance and proactive measures to enjoy our health and to minimize the use of medications. Dr. Chow Kwan is fluent in Mandarin and Cantonese.

Mary Lowen, M.D.
Mary Lowen, M.D.

Attended medical school at the University of Kansas. Dr. Lowen performed her postgraduate work at the University of Irvine in 1977. Dr. Lowen started practicing medicine in 1978. Dr. Lowen is also a fellow of AAFP and is board certified in family practice.

Nathalie M. Michaud, M.D.
Nathalie M. Michaud, M.D.

Received her medical degree from the University of Sherbrooke, school of medicine, in 1995 and completed her residency in Family Medicine at the hospital center of the University of Sherbrooke in 1997. Was in active practice in Montreal, Canada until 2001 when moved to Connecticut where she practiced 10 years. Dr Michaud is board-certified in Family medicine in the United States and in Canada. She is also an active member of the American Academy of Family physicians as well as the College of Family Physicians of Canada. Her interests in Family Medicine encompass women's health, preventive care as well as adolescent and geriatric medicine. She speaks French fluently.

Maeve O'Regan, M.D.
Maeve O'Regan, M.D.

Dr. O'Regan attended the University of Cape Town, South Africa and practiced medicine in Cape Town until moving to the United States. She spent three years at Highland Hospital in Oakland, CA and became board certified in Internal Medicine in 1997. She enjoys hiking, kayaking and quilting in her spare time.

Grishma Jivantika Patel, M.D.

Graduated from Universidad Tecnologica de Santiago, in the Dominican Republic in 1986, and completed her post-graduate Internal Medicine residency at Yale University affiliated hospital. Dr. Patel started her career working in a non-profit community based clinic in Oakland, and prior to joining WCMG she worked in her own private practice in Walnut Creek. She has also served as Medical Director for a home health agency. She is on staff at John Muir Medical Center. Dr. Patel speaks English, Hindi, and Gujarati fluently and is proficient in Spanish. In her free time, she enjoys spending time with her family, gardening and vacationing on the coast.

Catherine Wang, M.D.
Catherine Wang, M.D.

Received her medical degree from UMDNJ - New Jersey Medical School in 1998 and completed her residency in family practice at UCSF Family and Community Medicine Residency Program in 2001. She is Board Certified in Family Practice and member of the American Academy of Family Physicians (AAFP) and California Academy of Family Physicians (CAFP). She and her husband Dave reside in Walnut Creek with their 2 daughters. She enjoys hiking, running, tennis, and music.

Diane Wight, M.D.
Diane Wight, M.D.

Attended U.C. Berkeley in 1974 - 1977. Dr. Wight studied pre medicine with a major in Spanish. She received her medical degree from the Medical Academy of Warsaw, Poland in 1983. She completed a 3-year residency in Family Practice in 1986 at the Williamsport Hospital in Williamsport, PA. and is Board Certified in Family Practice.

Our Staff