Clinicians


Kenneth Ducker, MD                                      Castro Valley Office
Dr. Kenneth Ducker received his undergraduate degree from Oberlin College in Ohio and attended medical school at New York University. After completing his medical degree, he completed his residency at Children's Hospital, Oakland. He is certified by the American Board of Pediatrics and he has been supervising and teaching resident physicians in both inpatient and outpatient settings at Children's Hospital since 1978. In 1995, he was awarded the Children's Hospital Community Physician of the Year for his commitment to primary care and community service. For seven years, he was Chief of the Division of General Pediatrics at Children's. Dr. Ducker joined PPMG in 1998, after having practiced in the Castro Valley community for many years. In his free time, he enjoys running, music, hiking, movies and spending time with his wife, grown children, and grandchildren.

Michael Usem, MD                             Oakland Office
Dr. Michael Usem came to Stanford University from Minnesota for his undergraduate work and then traveled back to the University of Minnesota for medical school to complete his M.D. He finished his residency at Children's Hospital, Oakland, and has been supervising and teaching resident physicians and students at both Children's Hospital, Oakland and UC San Francisco medical school. He is certified by the American Board of Pediatrics and is a founding partner of Primary Pediatric Medical Group. Dr.Usem is currently President of the Medical Staff at Alta Bates Summit Medical Center.  In his spare time he enjoys music, walking, tennis, hiking, skiing, and traveling with his wife and two boys.


Patricia Chiang, MD                   Oakland Office                    
Dr. Patricia Chiang received her undergraduate degree from UC Berkeley and her medical degree from Temple University, graduating with honors. She has been supervising and teaching resident physicians at Children's Hospital, Oakland, and has consulted with Thunder Road, an adolescent drug rehabilitation clinic in Oakland. Dr. Chiang has been with Primary Pediatric Medical Group since 1996. She is certified by the American Board of Pediatrics and speaks some Mandarin. When she is not seeing patients, she enjoys reading, traveling, and spending time with her husband and their three active children, including a set of twins!


 

Laura Balestreri, MD                         Castro Valley Office
Dr. Laura Balestreri received her Bachelor of Science degree from Illinois Wesleyan University. She moved to the Bay Area to work in the biotech industry, but, unsatisfied with laboratory science, decided to go to medical school and moved back to the Midwest. She graduated from Saint Louis University Medical School with honors. Having greatly missed California, she returned and completed her pediatric residency at Children's Hospital Oakland in 2005. Shortly thereafter, she joined Primary Pediatric Medical Group. She is board certified by the American Board of Pediatrics and is moderately fluent in medical Spanish. In her free time, she enjoys hiking, quilting, traveling, spending time with her husband and chasing after her  daughter and son.

Erica Glenn, MD                                       Castro Valley Office

As a Board Certified pediatrician, Dr. Glenn joined PPMG in July 2016 at our Castro Valley office. She attended St. Louis University School of Medicine after earning an undergraduate degree at the University of North Carolina at Chapel Hill, NC with a BA degree in Exercise and Sport Science with honors. Her residency training was at UCSF Benioff Children's Hospital in Oakland where she attained the distinction of Chief Resident. She has volunteered as a mentor for the Community Health and Adolescent Mentoring Program for Success (CHAMPS) and was a licensed and certified athletic trainer. We are very pleased to have Dr. Glenn join our team and now we will all have to get in shape!


Fiona Marion, MD                                                      Alameda Office

Dr.  Marion completed medical school at Trinity College, Dublin, Ireland and trained in Ireland and Australia before moving to the United States in 2010. After completing a pediatric residency at Children's Hospital and Research Center in Oakland, she spent a year as a clinical fellow in Pediatric Pulmonology at UCSF. She is Board Certified by the American Academy of Pediatrics and joined PPMG in the summer of 2014. In her spare time, she enjoys hiking and spending time outdoors with her family. She is currently accepting new patients in our Alameda office.

Katherine Huffman, MD                                      Alameda Office

 Dr. Katherine Huffman completed medical school at the  University of Virginia and her Pediatric Residency at Children's Hospital and Research Center in Oakland. She is Board Certified by the American Board of Pediatrics and has many years of volunteer work at clinics, hospitals, mentoring programs, and boys & girls clubs. She is an avid runner, enjoys skiing, yoga, knitting and spending time with her family.  She is pleased to be accepting new patients in our Alameda office.                   


Georganne Walker, PNP                                                 Alameda Office
Georganne Walker, P.N.P., IBCLC, completed her B.S. in Nursing at University of San Francisco  and received her Masters in Nursing from UCSF. She became a certified pediatric nurse practitioner in 1994 and an internationally board certified lactation consultant in 2002. Georganne worked as a staff nurse at Children's Hospital Oakland from 1985 until 2002 where she worked in the neonatal intensive care unit, the emergency department, and the Pediatric Urgent Referral Line. From 1994-2004 she was with Rainbow Pediatrics as a Nurse Practitioner and Lactation Consultant. When not busy at Primary Pediatric Medical Group (PPMG), Georganne  facilitates a breastfeeding support group at Alta Bates Hospital where she also works as a lactation consultant. Georganne joined PPMG in December 2004 as a Nurse Practitioner and Lactation Consultant. She is married and enjoys spending time with her husband and two college-aged sons. She also enjoys hiking, cycling, gardening, cooking, and sewing.


Jennifer Wineman, FNP                                  Alameda Office
Jennifer Wineman, FNP, CPNP completed her undergraduate degree in nursing from California State University, Chico. She worked for 10 years as a critical care nurse. Jennifer began her Masters Degree Program at Sonoma State University and joined PPMG in 1996 as a student Nurse Practitioner while fulfilling her pediatric internship.  Board Certified as a Pediatric Nurse Practitioner, Jennifer became part of the clinical staff at PPMG in 1998. In 2008 Jen left the Practice to spend more time with her young son, and returned in 2010. When not busy at PPMG, Jen loves spending time with her husband and son, cycling, swimming, and gardening.




Bruce Horwitz, MD                                          Oakland Office
Dr. Bruce Horwitz received his undergraduate degree from U.C. Berkeley, and completed medical school at Washington University in St. Louis. He is board certified by the American Board of Pediatrics and has been practicing in his hometown of Oakland for more than 40 years. Dr. Horwitz is one of Primary Pediatric Medical Group's founding physicians, helping to form the group in 1996 after many years in solo practice. He was formerly the doctor for the Childrens Home Society, the Oakland Athletics Major League Baseball, Oakland Marathon and the Alcatraz Triathalon. Not surprisingly, he enjoys sports medicine and is rewarded with success treating warts and ADHD. When not seeing patients, Dr. Horwitz enjoys his grandkids, biking and running marathons. In fact, he has run a marathon on all 7 continents!