Progressive Evaluation & Referral Center (PERC)

What is PERC?

The Progressive Evaluation & Referral Center (PERC) is a primary care clinic for patients with complex medical needs. PERC serves >200 individuals from around the Southwestern Pennsylvania region with diagnoses that range from Autism Spectrum Disorder to cerebral palsy to rare genetic diseases.

It is located in the General Internal Medicine Office clinic at UPMC Montefiore Hospital 9 South, in the Oakland neighborhood of Pittsburgh. Usually, we become the patient’s primary care provider (PCP), but for individuals who live far from Pittsburgh (>2 hours away) we can serve as a consultant for the local PCP.

Who is a Good Candidate for PERC?

To be seen at PERC, an individual should be referred by another provider; a patient or caregiver may also initiate the process. They should call 412-692-4888 and ask for “Firm 3” or “PERC.”

PERC candidates must meet 2-3 of the following criteria:

  • multiple complex medical conditions since childhood
  • technology-dependent medical care
    (ventilator, tube feeds, wheelchair, etc.)
  • intellectual or developmental disability

The ideal candidate is transitioning from the pediatric world between the ages of 18 and 26 and in a relatively stable condition; patients over the age of the 30 may be accepted on a case-by-case basis.

We may refer individuals with Sickle Cell Disease, Trisomy 21 (Down Syndrome), and Cystic Fibrosis (CF) to specialized clinics for those conditions. If a patient is not a good fit for PERC, s/he can be seen by any of the GIMO physicians. Each of our PERC physicians also takes care of non-PERC patients.

What Makes PERC Special?

PERC patients benefit from physicians who trained for 4 years in both Internal Medicine (care of adults) and Pediatrics (care of children). They also get longer appointments, individualized to their special needs. The clinic is wheelchair accessible and has a laboratory onsite.


How did PERC get started?

Dr. Alda Maria Gonzaga founded PERC in 2006 to serve a unique and growing population: young adult patients with complex medical histories who were aging out of pediatric care. Dr. Reed Van Deusen came on board to further that mission in 2013. Dr. Kristen Ann Ehrenberger joined the practice as Director in 2020.

Who Are We?

Kristen Ann Ehrenberger, MD PhD


Dr. Ehrenberger grew up in Baltimore, attended college in St. Louis, and earned her doctoral degrees in Champaign, IL. Her PhD is in the history of medicine with a focus on nutrition and public health, and she traveled to Germany to do research in libraries and archives. While in graduate school, she co-authored a book about how individuals and societies make memories. She chose to complete her clinical training in Pittsburgh so that she could join PERC when she finished. The theme of Dr. Ehrenberger’s career is “inter-disciplinarity,” or bringing people from different backgrounds together. She is dedicated to working with patients, caregivers, community partners, and specialists to smooth the transition from pediatric to adult care.

Alda Maria Gonzaga, MD MS

Dr. Gonzaga hails from Maryland and studied at Wellesley College before completing medical school, residency, and a clinician-educator fellowship at the University of Pittsburgh. Her clinical interests include women’s health as well as complex care. Her research and teaching emphasize the inclusion of women and minorities in medicine through mentoring and implicit bias training, innovations in graduate medical education, and communication between patients and providers as well as among providers. In addition to the labor of love that is PERC, Dr. Gonzaga was Program Director for the UPMC Internal Medicine-Pediatrics residency from 2008 to 2020; she is currently Associate Dean for Student Affairs at the University of Pittsburgh School of Medicine.

Reed Van Deusen, MD MS

Dr. Van Deusen is a native of Pittsburgh. He did his medical school and residency training in Cincinnati, but he was happy to move back to the Steel City in 2006. After he completed a clinician-educator fellowship in 2008, he joined the PERC team. He is humbled and honored to be one of the few physicians in the region whose clinical niche is providing primary care for special-needs adults. In addition, he has served many educational roles at the University of Pittsburgh School of Medicine, most recently as Assistant Dean for Human-Based Simulation Education. The Standardized Patient (SP) Program he runs works with multiple kinds of learners (healthcare professions students, educators, social work students, law students, etc.) on skills in communication, physical examination, and/or clinical reasoning. He is also actively engaged in the education of the Internal Medicine-Pediatrics residents. He considers himself lucky to have found such a fulfilling career where he can serve the community, both in caring for special-needs and normal-needs patients as well as training future generations of professionals.

Contact Us

Division of General Internal Medicine Academic Offices

UPMC Montefiore Hospital
Suite W933
Pittsburgh, PA 15213

Patient/Clinical Inquiries


Administrative Office