About Us

Prism Health offers a safe, affirming, and non-judgmental space where all members of the lesbian, gay, bisexual, transgender, and queer community can obtain the compassionate and culturally effective health care they need and deserve.

We prioritize inclusivity to ensure that all members of the LGBTQ+ community can access affirming and high-quality health care. Patients do not have to be lesbian, gay, bisexual, transgender or queer to receive care, but services will focus on addressing the sensitive issues of sexual and gender minorities and their families and friends.


Mandy Wilson McKimmy | DNP, FNP-C, AAHIVS, Medical Director

Pronouns: She/Her/Hers

Mandy Wilson McKimmy is a certified Family Nurse Practitioner with over 15 years of experience in primary care.  She attended The University of Texas Medical Branch (UTMB) and earned her Bachelor of Science in Nursing in 2000 and her Master of Science in Nursing, Family Nurse Practitioner Track in 2003.  She worked in the Houston area for UTMB in Family Practice and Pediatrics for a number of years before relocating to Oregon.  In 2013 she completed her Doctorate of Nursing Practice (DNP) at The University of Alabama.  She has been working for Oregon Health & Science University for the past six years as an assistant professor in the FNP and DNP programs while continuing to practice in primary care, with a focus on young adults and sexual health.  Mandy has worked closely with doctoral students completing projects on LGBTQ+ health, including the use of PrEP in primary care and working to decrease health care disparities in LGBTQ+ populations in rural Oregon.  In addition to practicing and teaching, Mandy is actively involved in Nurse Practitioners of Oregon and is serving her fourth year as the state representative of Oregon for the American Association of Nurse Practitioners. Mandy and her partner have six children and enjoy spending time as a family doing outdoor activities such as wake-boarding, hiking, camping, and skiing.

Dr. Diana Antoniskis | MD, IDM, AAHIVS

Pronouns: She/Her/Hers

Dr. Antoniskis was born and raised in Nebraska and graduated from the University of Nebraska Medical Center. Her internship was at San Francisco General Hospital during the early years of the HIV epidemic, and she went on to pursue additional training in both Internal Medicine and Infectious Diseases at Los Angeles County/USC Medical Center; she is board certified in both of those specialties. She moved to Portland in 1991 to join Kaiser Permanente, where she worked in the Immune Deficiency Clinic (IDC) and the general Infectious Disease department until her retirement in 2017. During her time at KP, she also served as the Director of Clinical Research for the IDC and was Chief of that department for approximately 10 years. She served as the Director of Operations for Medical Specialties for Northwest Permanente from 2012-2017 in addition to her clinical practice.

Connie Silverman | DNP, FNP-C, Family Nurse Practitioner

Pronouns: She/Her/Hers

Connie Silverman is a dedicated family nurse practitioner who enjoys working with patients of all ages and backgrounds. She completed her Doctor of Nursing Practice at Oregon Health & Science University (OHSU) and currently teaches at OHSU in the family nurse practitioner program. She believes strongly in the value of preventative care and in working with patients to develop a plan of care that fits their goals. Her clinical interests include LGBTQ+ care, family planning, and addiction medicine. Originally from Minnesota, Connie settled down in the Pacific NW in 2012 and loves spending time exploring the mountains with her family.

Joshua Oppenheim | PA-C, Physician Assistant

Pronouns: He/Him/His

Joshua Oppenheim is a certified Physician Assistant who completed his Masters in Physician Assistant Studies at Pacific University. He has researched and lectured on the knowledge and attitudes of providers as it pertains to standards of care for men who have sex with men, and has further lectured on prescribing PrEP. Josh has clinical experience working with LGBTQ+ patients in Oregon, Washington, and beyond, and has volunteered with many youth centered organizations including Camp Erin and the Boys and Girls Club. Josh was born in Central Oregon and has lived abroad on three continents—most recently in South America where he was able to improve his conversational and medical Spanish. He enjoys traveling, trying new foods, and exploring all that the Pacific Northwest has to offer.


Danielle Walsh | LPC

Pronouns: She/Her/Hers

Danielle Walsh is a licensed professional counselor who is passionate about providing culturally competent, trauma-informed mental health services to the LGBTQ+ community. She holds a masters degree in pastoral counseling from Marymount University and recently completed a post-graduate certificate program in sexual health from the University of Michigan, specializing in sex therapy. Danielle has experience working with trans and gender non-conforming clients, and addressing issues related to religion and spirituality, sexuality, grief and loss, and trauma. Danielle recently moved to Portland from Boise, Idaho and enjoys biking, thrift store shopping, and spending time with her cat, Puff. For more information about their approach to mental health practice please click here.

A. Michael Duncan | PsyD

Pronouns: He/Him/His

Mike Duncan is a licensed psychologist who completed his doctoral degree in clinical psychology at Pacific University in Hillsboro, Oregon.  He received his bachelor’s degree in psychology from the University of Colorado at Boulder.  He has a generalist background in mental health working with ages 12 and up, in group, individual, family, and crisis therapy, in community outpatient and residential settings, and with a broad range of diagnoses and treatment needs.  He has performed research regarding sexual minority adolescent risk and protective factors in addition to internalized sexual prejudice and sense of belonging in sexual minorities.  He has lived in the Portland area since 2011 and enjoys yoga, bicycling, and exploring the Pacific Northwest. For more information about their approach to mental health practice please click here.


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Pronouns: They, Them, Theirs