About → Surgical and Office Staff

Dr. Alan C. Wittgrove, M.D.

Dr. Alan Wittgrove was born and raised in Missouri. He graduated from the St. Louis College of Pharmacy in 1972. He then attended the University of Missouri School of Medicine, graduating as a Doctor of Medicine. He served his internship and received his surgical residency training at San Diego Naval Hospital. Dr Wittgrove is board certified in general surgery and a Fellow of the American Society for Metabolic and Bariatric Surgery. He served as a staff surgeon at Naval Hospitals in the Philippines, and Bremerton, Washington, and on the surgical teaching staff at San Diego Naval Hospital. He is a member of the American Society for Metabolic and Bariatric Surgery, San Diego Society of General Surgeons, San Diego County Medical Society, American College of Surgeons and the California Medical Association. Dr Wittgrove served as the president of the American Society for Metabolic and Bariatric Surgery in 2003-2004.

Dr. Wittgrove pioneered the laparoscopic approach of gastric bypass surgery, performing the first laparoscopic gastric bypass as primary surgeon in the world, in November 1993. He and his program have performed over nine-thousand bariatric procedures. Patients seek Dr. Wittgrove's expertise from all over the country to perform their bariatric procedure including gastric bypass, sleeve gastrectomy and revision surgery.

Dr Wittgrove is widely published and has taught dozens of surgeons throughout the US and the world his surgical techique.

"I feel very fortunate to see patients get healthier and resolve many health conditions that are often seen as unachievable by their doctors. Seeing someone high cholesterol go away, blood pressure normalize or diabetes resolve after surgery is very rewarding, it makes for a good day at work."

Dr. Konstanzer

Dr. Konstanzer was born and raised in Mobile Alabama. He received his medical degree from Loma Linda University. He served in the Navy as a flight surgeon. He then started a general practice in San Diego and began assisting in Bariatric Surgery. He has assisted on over 10,000 Bariatric surgeries and has been assisting Dr. Wittgrove for over ten years. Dr. Konstanzer is married with one son and two daughters. He enjoys golf, tennis, skiing and flying. He enjoys seeing the wonderful changes in our patients lives.

Tracy Martinez, RN, BSN ~ Program Director

Our multidisciplinary support team is led by our program director, Tracy Martinez RN. Tracy has been working in the field of bariatric surgery for over 20 years. She began her nursing career in acute care as a PACU nurse and a hospital educator. It was during that time that she cared for patients undergoing bariatric surgery and became interested in the specialty. In 1998, Tracy changed her path and dedicated her career to the field of metabolic disease and bariatric surgery as a Certified Bariatric Nurse. She feels very fortunate to work in this field and to have had the privilege of teaching other professionals and presenting on the care of bariatric patients throughout the world. She is published in Critical Care Nursing and five medical textbooks on metabolic surgery. She has also been part of the team on several published medical studies.

Tracy is the past president of ASMBS Integrated Health, Co chair of ASMBS Multidisciplinary Care Committee and a Board Member for the the Obesity Action Coalition. She consults nationally for several corporations in the field of Bariatrics. She is the past chair for the International Federation of Surgery for Obesity and a founding member of the Governing Board of the Surgical Review Corporation (the corporate tasked with certifying "Centers of Excellence" in bariatric surgery).

"My goal is to educate patients as they prepare for surgery and coordinate our team to partner with our patients so they can achieve optimal health and weight loss maintenance. It takes a dedicated community to support all aspects of well-being. I strive to create that for our patients."

Dr. Ryan Dominguez, M.D.

I am a native southern Californian growing up in the Los Angeles suburb of Claremont. I then attended the University of California, San Diego for my undergraduate degree; obtaining a BS in Biology, and a minor in Spanish Literature. I was a merit scholar while attending Medical College of Pennsylvania-Hahnemann School of Medicine, graduating in 1999. I then came back to California to do my internship at Grossmont Hospital in La Mesa and finished my residency in Family Medicine at Long Beach Memorial Hospital.

I started private practice in La Jolla, CA in August of 2002 and now practice both there and in Scripps Ranch. I developed an interest in Sports Medicine and Preventative Health and continue those focuses today. In my free time I enjoy playing soccer, spending time with my family, especially my 18 month old daughter Simone and of course rooting the Chargers to victory.

Sue Kuhnsman

Sue Kuhnsman is our patient coordinator. She is responsible for coordinating patient appointments and triaging patient questions. Her patience and compassion is conveyed even on the phone. She is dedicated to treating each patient as an individual, realizing that everyone approaches their disease and treatment differently. After a career in Education and Art Therapy, she found her true passion--what she calls her "bliss"--in helping patients with many aspects of care before and after surgery. In addition, Sue shares her experience undergoing bariatric surgery nine years ago at Wittgrove Bariatric Center with others. Sue says that it is a joy to work with the family of patients of WBC and to assist on their pathway to better health and well-being.

Ronee Jackson

Ronee Jackson is our insurance analyst. She works diligently with patients to learn about their insurance coverage and the requirements for surgery approval. She advocates for each patient diligently through the entire approval process. Ronee is very organized, persistent and concise. These three attributes are an immense benefit in pursuing insurance approval. Ronee says that one of the greatest things about her career is that she feels "so honored to be the one that calls them with the great news of surgery approval!" Ronee is married to a wonderful, supportive man and has three children.

Cait Hartney, BS

Cait Hartney is our clinical medical assistant and research coordinator for Wittgrove Bariatric Center. She from The George Washington University in Washington, D.C. where she studied cognitive neuroscience and art history. Originally from San Diego, she plans to continue her studies in medicine. She feels our program has taught her what it means to provide excellent patient care and comprehensive medical treatment. "It's amazing to hear from patients who are twenty years out from surgery and still thank Dr. Wittgrove for changing their life. Their gratitude is what drives me to provide you with the best possible care through your weight-loss journey".

Katelyn Castro, ACSM-CPT

Katelyn Castro is our fitness coordinator. Kate is passionate about exercise. Her training brings a wealth of knowledge to our patients on the benefits of daily movement. Kate understands that every patient comes to the program with varying levels of fitness, knowledge and comfort. She will work with patients individually to help them learn why, how and when to exercise. Kate also has a interest for nutrition and is currently studying to get a degree in nutrition.

Jenny Driessen – Program Lead

Through a circuitous path, Jenny has ended up at Wittgrove Bariatric Center. At 35, she was diagnosed with breast cancer and realigned her priorities. She left the stressful career as a realtor and pursued one in health care and overall wellness. She began working at a non-profit that aims to improve health care and lower health care costs while earning her certification as a yoga instructor. Jenny follows her heart and insists on making a difference each and every day. Now, her mission at Wittgrove Bariatric Center is to help patients achieve better health through facilitating follow up appointments and wellness programs for patients that are meaningful, manageable and fun! Maintaining mental and physical wellness is a lifelong journey, and doing it together is the best way to set ourselves up for success.


Miss Emily is our certified service dog. She is full of love and compassion. When she isn't in our office, she is "doing rounds" at assisted living centers.

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