Andrew Posselt


Bariatric and transplant surgeon

Dr. Andrew Posselt, a bariatric and transplant surgeon, is co-director of the Pancreatic Islet Transplantation Program at UCSF Medical Center. He specializes in adult and pediatric kidney, liver and pancreas transplantation, as well as laparoscopic and open (traditional) bariatric surgery.

In addition to caring for patients, Posselt conducts research on pancreatic islet cell transplantation, a procedure that can allow people with type 1 diabetes to discontinue insulin therapy. He also investigates mechanisms by which a transplant recipient's body rejects or tolerates tissue from a donor who isn't genetically identical, and he studies the metabolic and biochemical consequences of bariatric surgery.

Posselt earned his medical degree and a doctorate in immunology from the University of Pennsylvania. He completed residencies in internal medicine and general surgery as well as a transplant fellowship at UCSF, before joining the staff in 2003.

Posselt is a member of several professional and honorary societies, and has given presentations on transplant issues related to patient care and research. At UCSF, he supervises residents and fellows in transplant services and general surgery.

  • Education

    University of Pennsylvania School of Medicine, 1993

  • Residencies

    UCSF Medical Center, Internal Medicine, 1996

    UCSF Medical Center, Surgery, 2000

  • Board Certifications

    Surgery, American Board of Surgery

  • Academic Title


  • Languages





I consciously take my time with patients. If they have questions, I’ll listen. It makes a huge difference.

Where I see patients (6)

    My reviews


    Overall Experience
    70 Ratings
    Explained things in a way that was easy to understand
    70 Ratings
    Did the doctor pay attention to your concerns
    69 Ratings
    Gave easy to understand instructions about taking care of health problems or concerns
    67 Ratings
    Knew the important information about your medical history
    70 Ratings
    The provider showed respect for what you had to say
    70 Ratings
    The provider spent enough time with me
    69 Ratings
    Decorative Caduceus

    Treatment of Type I Diabetes by Islet Transplantation Into the Gastric Submucosa Study Protocol

    off insulin therapy for at least 1 week and all of the following criteria are met: HbA1c < 6.5% or a > 2.5% decrease from baseline; Daily fasting capillary glucose should not exceed 140 mg/dL (7.8 mmol/L) more than 3 times in th...


    My work

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