Tempe Office Providers

We currently have seven providers practicing out of our Tempe office. Please feel free to browse the bios of each of our providers below.

Joseph Piacentine, M.D., F.A.A.P.

I have been in practice since 1987 when I joined Mesa Pediatrics. I was born and raised in Colorado and attended college at the University of San Francisco, majoring in biochemistry and philosophy. I returned to Colorado for medical school at the University of Colorado. I moved to Phoenix to complete my pediatric residency at Phoenix Hospitals Affiliated Pediatric Program at Phoenix Children's Hospital and Maricopa Medical Center. I was Chief Resident in Pediatrics my last year. I am certified by the American Board of Pediatrics and have been re-certified twice. My wife is a pediatrician also. We have a college-age son, two dogs and a cat. Here are some of my favorite links; Keep Kids HealthyLD OnlineDrGreene.comDenver Broncos, and Epicurious.com.

Kristin McCleland, M.D., F.A.A.P. 

My name is Kristin McCleland. I grew up in Wisconsin, and moved to North Carolina to attend Davidson College for my undergraduate degree in psychology. I taught and coached middle school before heading to medical school at East Carolina University. I completed pediatric residency training at Phoenix Children's Hospital/Maricopa Medical Center, and received board certification from the American Board of Pediatrics. I enjoy spending time with my husband, Jim and my kids, Flynn and James. I love basketball, hiking, reading, and cheering on the Green Bay Packers.


Michelle Valenzuela, M.D., F.A.A.P.

Hi! I’m Michelle Valenzuela. I grew up in Oracle, Arizona. I stayed close to home to pursue my dream of becoming a pediatrician. As a graduate of the University of Arizona College of Medicine, I completed my pediatric residency training at Phoenix Children’s Hospital/Maricopa Medical Center. I have been in private practice since 2005 and am certified by the American Board of Pediatrics. My husband and I have lived in the East Valley for over 10 years. We are the proud parents of 2 beautiful children.


Darcey Winterland, M.D., F.A.A.P.

Hi!  My parents, brother and I followed the Chicago Cubs from Illinois to Mesa when I was five.  My first role at Mesa Peds was actually as a patient of our beloved founder, Dr. Kerr.  I attended the University of Arizona for college, where I studied Biology, Spanish and Wildcats Athletics. Ever a Wildcat, I attended the U of A for medical school then completed my residency at Phoenix Children's Hospital/ Maricopa Medical Center Pediatric Residency Program. I am board certified by the American Board of Pediatrics and a Fellow of the American Academy of Pediatrics. I have an incredible husband and three amazing children.  My hobbies include cooking, pilates, reading, and travel.  I love spending time with my wonderful family and friends, hiking, playing and watching sports and cheering on my Cubs, Bears and Wildcats.


Ashley Navarro M.D.

Hi there! My name is Ashley Navarro and I'm very excited to be a part of Mesa Pediatrics. I grew up in Chandler then moved to Tucson where I received my Bachelor of Science in Physiology, medical degree, and residency training at the University of Arizona. My husband is an Emergency Medicine physician and we have an adorable daughter. I enjoy spending time with my family and look forward to meeting yours!


Jennifer Gibler, PA-C

Hi. I'm Jennifer Gibler and I've been practicing pediatrics since 1995. I received my B.S. degree as a Physician Associate from the University of Oklahoma College of Medicine. I also received a B.S. degree in fitness and wellness management from Southern Nazarene University. I'm certified by the National Commission of Physician Assistants. I love sports, traveling, and spending time with my family.


Buffy Patterson, PA-C

Hi. I'm Buffy Patterson, PA-C. I received my Masters of Medical Science Degree in Physician Assistant Studies from Midwestern University in 1998. I have worked in Pediatrics and Family Practice since then. I also have a Bachelors of Science in Psychology from Arizona State University (Go Devils!). I am married with 3 wonderful children, 2 sons, and a daughter. For my "me time", I enjoy Bikram Yoga, training for and competing in triathlons, reading, and cheering my kids on at all of their events.