Current Renal Fellows

First-Year Fellows 

Shannon Lyons, DOLyons

Hometown: Rockford, Washington 

Medical School: Pacific Northwest University of Health Sciences 

Residency: Parkview Health System

Research/Clinical Interests: I love teaching especially when it comes to electrolytes, acid/base, and renal physiology. I also have a special interest in ESRD and renal replacement therapies and how we can improve the quality of life of ESRD patients.

Hobbies: Reading, hanging out with my dog Honey, trying (and usually failing) to grow my little house plants, and exploring the many breweries that Colorado has to offer!

Why did you choose the University of Colorado? The quality of the teaching and wide variety of clinical experience was what initially attracted me but what really won me over was the people. The faculty is incredible and really loves to teach and I could sense how collegial the atmosphere was amongst the fellows.


Marissa Martin, MD
martin, marissa

Hometown: St. Paul, MN

Medical School: University of Iowa

Residency: University of Colorado

Research/Clinical Interests: Use of Crit-Line/relative blood volume monitoring in hospitalized patients receiving dialysis, treatment of pregnant women with CKD (pre-pregnancy counseling in addition to management during pregnancy), and medical education.

Hobbies: Running, patio hopping, playing in the park with my puppy, spending as much time in the mountains as possible, hiking, camping, skiing, and paddle boarding with my fiancé

Why did you choose the University of Colorado? After interacting with the nephrology department during my time in residency here, I couldn't imagine going anywhere else. It is a fantastic group full of welcoming, driven, accomplished, brilliant people and I can't wait to learn from them for two more years. I'm excited for the diversity of patients and conditions between our three sites and the vast clinical, medical education, research, and mentorship opportunities available. 


Abdul-Rehman Syed, DOAbdul-Rehman Syed

Hometown: Dallas, TX


Medical School: Lake Erie College of Osteopathic Medicine


Residency: The University of Texas Medical Branch at Galveston


Research/Clinical Interests: Peritoneal/home dialysis, Glomerulonephritis, AKI's, medical education


Hobbies: I enjoy reading, trying new cuisines, exploring museums, and binge-watching TV


Why did you choose the University of Colorado? I chose the University of Colorado because it is a top-ranked nephrology program where I knew I would get excellent training. The faculty I met during the interview were friendly and very passionate about medical education. I knew this program would help me carve out the kind of career I wanted.  The program really emphasizes fellow wellness. And overall, Denver is just a great city to live in! 


Manny Urra, MDManny Urra

Hometown: Miami, FL


Medical School: Creighton University, Omaha NE


Residency: University of Colorado, Denver CO


Research/Clinical Interests: Medical Education, Critical Care Nephrology, Electrolyte Derangements


Hobbies: Weightlifting, cycling, and spending time exploring with my wife, Claire, and one year old baby, Esme


Why did you choose the University of Colorado?

I was very impressed with how happy and clinically excellent the first-year fellows were after rotating with them as a resident. The faculty is extremely approachable and motivated to help you succeed based on your career goals. The three-hospital system allows for exposure of diverse patient populations.

Chris Yang, MD
Yang, Chris

Hometown: Wichita, KS

Medical School: University of Cincinnati

Residency: Indiana University

Research/Clinical Interests: 

Home dialysis, healthcare disparities, hypertension, cardiorenal syndrome and diuretic resistance

Hobbies: Dining; (tiki) cocktails; computer, board, and card gaming; crossword puzzles; watching the NBA and MLB; reading science fiction; listening to bluegrass, (classic) country, hip hop, and EDM

Why did you choose the University of Colorado? My impression on the interview day was that this was the program that most genuinely cared about the education and wellness of its fellows. The world-renowned faculty, the beauty and excitement of Colorado and Denver, and the overall happiness of the fellows were all major draws as well.


Second-Year Fellows 


Cameron Charlow, DOCameron Charlow

Hometown: Los Angeles, California

Medical School:  Alabama College of Osteopathic Medicine

Residency: University of Nevada Las Vegas

Research/Clinical Interests:  Vascular Access, Renal Replacement Therapies,  Diet Related Effects on CKD, CKD in African Americans

Hobbies: I am a huge Star Wars fan. I am also a big sports fan, watching and playing. Trying new foods, music, exploring new places and languages.

Why did you choose the University of Colorado? I chose the University of Colorado because they have a rich history of contribution to the world of nephrology with excellent training.  They have the flexibility to guide training toward your interest. It's located in a great city that has a multitude of activities.  The fellows were the happiest groups of fellows I interviewed with.

Amy Li, MD

Amy Li

Hometown: Honolulu, Hawaii


Medical School: University of Hawaii John A. Burns School of Medicine


Residency: University of Colorado


Research/Clinical Interests: I love electrolytes (especially hyponatremia), acid/base, AKI, CKD, and dialysis so... All of it! I'm also particularly interested in basic science research.


Hobbies: wildlife/bird photography, cooking, traveling, and kitty cats - I have three cats with more room to love (in my heart but not at home). Also, I am an avid not-skier, not-snowboarder, and I don't follow sports! 


Why did you choose the University of Colorado?

The faculty, no doubt! The faculty is full of supportive, kind-hearted people. I met the renal faculty as early as when I interviewed for residency, and they have supported me throughout the years without fail. They are so approachable and engaging and truly have the best interests of the learners at heart (medical students, residents, and fellows alike). Also, we're so lucky to rotate through three different hospitals - an academic hospital (UCH), our county and safety-net hospital (Denver Health), and the VA. What's not to love about CU?

Nervik Roy, DONervik Roy

Hometown: Born in Madison Heights, MI, but more recently Las Vegas, NV!


Medical School: Touro University Nevada


Residency: Valley Hospital, Las Vegas


Research/Clinical Interests: GNs, AKI, Acid/Base disturbances, Renal Cancer, and Interventional Nephrology


Hobbies: Lifting weights, eating out and trying new restaurants, relaxing on a beach while sipping a Piña Colada. 


Why did you choose the University of Colorado? Great program with phenomenal attendings and staff, and the fellows seem happy and want to be here!

Jack Rusing, MDJack Rusing

Hometown:  Prescott, Arizona

Medical School:  University of Arizona School of Medicine

Residency:  Creighton University School of Medicine (Phoenix) Program

Research/Clinical Interests: Glomerulonephritis, Peritoneal Dialysis, Artificial Kidney, Electrolyte Disturbances

Hobbies: Hiking, Running, Traveling, Mountain Biking, Skiing

Why did you choose the University of Colorado?  I choose the University of Colorado because it is one of the top nephrology fellowships in the U.S. with its renowned faculty, diverse clinical practice settings, and beautiful location. During my interview, I sensed the comradery between the fellows and their satisfaction with their training. 

Dual Adult-Peds Fellows


Angela Dixon, MDAngelina Dixon

Hometown: Pittsburgh, PA

Medical School: Pennsylvania State University College of Medicine

Residency: Tulane University Internal Medicine-Pediatrics

Research/Clinical Interests: Transitions of Care, Nephrology Medical Education, Quality of Life for ESRD Patients

Hobbies: Singing, writing/arranging music, working on my latest Pinterest fail, hiking, biking, skiing, and doing whatever it takes to tire out my Australian Shepherd, Oaklie

Why I chose Colorado: The program is very fellow-centric! I felt that I would get a great education and incredible mentorship and would be supported in my individual career goals, whatever those may be.

Shrey Purohit, MDPurohit, Shrey

Hometown:  Los Angeles, CA

Medical School: University of Michigan Medical School

Residency:  Duke University

Research/Clinical Interests:  Long term outcomes for CKD in younger populations, inherited kidney diseases, immunology

Hobbies:  reading, cooking, building computers

Why did you choose the University of Colorado? The University of Colorado provided me with the opportunity to create my own clinical pathway and explore my research interests. The faculty is extremely collegial and strongly invested in their fellows. Denver is also a great city to explore and has something for everyone!

Advanced Nephrology Fellow


Katherine Rizzolo‚Äč, MDRizzolo, Katherine MD

Hometown:  Franklin, MA

Medical School:  Tufts University - Boston, MA

Residency:   Maine Medical Center - Portland, ME

Research/Clinical Interests:   Immigrant health/access to dialysis for undocumented immigrants, healthcare disparities in nephrology, resident/trainee wellness

Hobbies:  Long-distance running, skiing, knitting, international travel, yoga, craft beer, gummy bears

Why did you choose the University of Colorado?  Fantastic research on and advocacy for, health inequalities and social justice.  Promotion of fellow wellness within the program.