Meet Our Providers

William E. Gilli MD Dr. Gilli is a Bakersfield native. He attended West High School and graduated from the USC School of Medicine.. Dr. Gilli is Board Certified in Internal Medicine. He is an avid runner.

Marsha Kaprielian FNP Marsha received both her Bachelor's and Master's in Nursing at California State University, Bakersfield. Prior to completing her education as a Family Nurse Practitioner, she was certified in critical care and emergency nursing. She is interested in women's health.

Tracy Simonsen ACNP Tracy Received her Bachlors Degree from Cal State University Bakersfield in Nursing. She then worked in Intensive Care Medicine for the next 7 years at Kern Medical Center. She obtain her Masters degree from UCLA in Nursing with a specialty as an Acute Care Nurse Practitioner.

Kevin Nelson, FNP

Kevin obtained his Family Nurse Practitioner and Physician Assistant Certificates from Stanford University and worked in Family Practice in Taft and Bakersfield for 6 years prior to joining Mesa West.