Meet our Urgent Care Medical Providers

Advanced Urgent Care & Occupational Medicine’s medical providers are dedicated to providing our communities across Colorado’s Denver metro area with compassionate healthcare. Our urgent care and occupational medicine medical providers have experience treating patients of all ages and have backgrounds ranging from urgent care and family practice to cardiology, internal medicine, and orthopedics.

Advanced Urgent Care & Occupational Medicine’s clinics are located in Brighton, Broomfield, Centennial – Southglenn, Denver – Central Park, Fort Lupton, Lafayette, Northglenn, Westminster – Federal, and Westminster – Wadsworth in Colorado. Our urgent care medical providers look forward to meeting you and serving our communities.

Tony Euser, DO, Owner, Physician

Owner and Physician Dr. Euser is a Colorado native and has spent most of his life near Brighton. He graduated from the University of Health Sciences College of Osteopathic Medicine in Kansas City, Missouri. Dr. Euser specializes in family practice, occupational medicine (Level II provider), and is FAA certified. He is also our Medical Review Officer (MRO).

Eager to make a difference in Brighton’s community, he opened his primary care practice, Platte River Medical Clinic, in January 2006. Dr. Euser realized the patients at his primary care practice didn’t have anywhere to get affordable treatment after hours in the Brighton area, so he opened Advanced Urgent Care & Occupational Medicine in 2012.

In his free time, Dr. Euser enjoys flying his plane, cycling, and skiing.

Patient Review

James M., 5 stars on Google

“Dr. Euser and his associates are some of the best medical professionals that you can find in the greater Denver metropolitan area. They are so attentive, kind, considerate, caring, and very professional. Five stars all the way for me. I would consider no one else for my medical needs.”

Tana Smith, MD, Medical Director

Dr. Tana Smith is a family medicine physician who practices the full scope of out-patient family medicine, including prenatal care. She is the Medical Director at Advanced Urgent Care & Occupational Medicine.

Dr. Smith has a passion for patient education and education in medical training. She believes a good rapport and understanding of a patient’s needs drives better health outcomes.

She is the former Medical Director at the Red Rocks Physician Associate program and a Commissioner on the National Accreditation Board for all Physician Associate schools in the U.S.

Dr. Smith is a Colorado native. She received her Doctor of Medicine degree from the University of Colorado School of Medicine and also has a Master of Science degree, in molecular genetics, from the University of Denver. Prior to her career as a physician, Tana Smith worked as a medical assistant and also managed an urgent care center.

Outside of work, Dr. Smith enjoys skiing, hiking, and swimming, as well as reading a good book. She has been married for 35 years, has 3 children and 5 grandchildren.

Patient Review

William P., 5 stars on Google

“Dr. Smith is a very knowledgeable and caring doctor.”

Sheree Montoya, FNP-C, Provider Lead

Family Nurse Practitioner Sheree Montoya has extensive experience in emergency care. She has always wanted to be in healthcare and enjoys taking care of others. She attended Regis University for her Bachelor’s Degree in Nursing and the University of Colorado at Colorado Springs for her master’s degree.

Sheree lives on a 60-acre farm with many animals. She also does professional photography for fun in her free time. She enjoys fly fishing and being outdoors.

Alexandra Williams, PA-C

Physician Associate Alexandra Williams has been a PA for over 5 years with prior experience in cardiology. Her passion for medicine and helping others led to her transitioning to the urgent care setting where she can better serve all ages and conditions.

Alexandra received her master’s degree in Physician Associate Studies from Keiser University in Fort Lauderdale, Florida.

Alexandra enjoys being outdoors, traveling, trying new restaurants, spending time with friends, her pup Zoey, and visiting family in Florida.

Alice Nguyen, PA-C

Physician Associate Alice Nguyen is a Delaware native who moved to Colorado in 2017 and is now living in Denver. She received her physician associate degree from Pennsylvania College of Technology in 2015. Before joining the Advanced Urgent Care team in 2018, she had over two years of experience in urgent care and family practice. From​ ​suturing​ ​a​ ​laceration​ ​to​ ​managing​ ​chest​ ​pains,​ ​she ​truly​ ​enjoys​ ​the​ different ​challenges that​ ​urgent​ ​care​ ​presents and how to solve them.

When she isn’t at work, Alice loves going to concerts and outdoor activities, such as hiking and kayaking.

Alice Tibbetts, PA-C

Physician Associate Alice Tibbetts brings a blend of primary care training and urgent care experience to Advanced Urgent Care. She loves the variety that urgent care provides – from treating an ear infection to stitching up a cut, all while working with her patients to provide them the best care possible. Alice graduated from the University of New England Physician Associate Program in Portland, Maine.

When she’s not at the office, Alice enjoys canoeing, hiking, and skiing with her husband. They have two cats.

Patient Review

5 stars on Google

“Extremely helpful, fast, polite, professional. PA Alice was extremely kind, friendly, and knowledgeable. I highly recommend this place for taking your kid for an injuries. Front desk and check-in was extremely nice too!”

Alicia Von Rivenburgh, FNP-C

Nurse Practitioner Alicia Von Rivenburgh worked in the neuro intensive care unit at UCHealth for 8 years. Her roles included senior nurse, preceptor, and PRN charge nurse. Acute care influenced her choice to return back to school to become a nurse practitioner. Alicia knew she would love the urgent care setting with the variety of illnesses seen there, the fast-paced environment, and the team approach to healthcare. She loves keeping her community members at home and healthy with their loved ones, and out of the hospital!

Alicia went to nursing school in Duluth, Minnesota, and graduated in 2013. She moved to Colorado when she was accepted into the
residency program in the Neuro Intensive Care Unit. She graduated from Regis University in 2020 with her family nurse practitioner degree.

She loves to hike with her black lab mix, Remie! She recently got married in 2019 to her husband, Ellis. They enjoy traveling and exploring new cities and breweries!

Patient Review

5 stars on Google

“Went in today for a quick removal of a stubborn toenail. Alicia V. was amazing. Very nice, and caring to not put me in to too much pain. Would love to see her again if I have to go back. Very comforting to know she had my best interest at heart. Thanks again!!!”

Allison Klein, NP-C

Nurse Practitioner Allison Klein is passionate about patient education. Her experience includes inpatient acute care and emergency care. Prior to joining Advanced Urgent Care & Occupational Medicine, Allison worked for three years in emergency care.

Allison’s undergraduate degree is a Bachelor’s of Science in Nursing (BSN) from Marymount University. She earned her Family Nurse Practitioner (FNP) Master’s degree from Marymount University.

Allison has a passion for open water swimming! She enjoys hiking, the fresh air, and downtime with friends.

Audra Dust, PA-C

Physician Associate Audra Dust received her master of medical science in physician associate studies from Indiana State University in 2015. Her bachelor’s degree is in biology. She has experience in urgent care and the emergency department.

Patient Review

Lisa C., 5 stars on Google

“This office is very efficient and welcoming. The staff, including Audra Dust, were very welcoming, patient, and empathetic. I highly recommend this team of professionals!”

Caitlin Trierweiler, PA-C

Physician Associate Caitlin Trierweiler worked in the ER for 9 years before moving to the urgent care setting. She was looking for more of a work-life balance after having her son. She attended South University in Savannah, Georgia, and she and her husband are originally from Indiana.

Caitlin and her husband John moved to Colorado in 2014. They fell in love with skiing and the mountains. Caitlin and John married in 2018 and they have a one-year-old named Nolan. They are expecting their second child in January 2022. They have a mutt named Rex. The rest of their family lives in Indiana.

Denyse Nizam, PA-C

Physician Associate Denyse Nizam has worked as a PA for 7 years. She started in orthopedics and sports medicine. Prior to working at Advanced Urgent Care she practiced in an orthopedic urgent care and hospital setting for 4 years. She looks forward to helping patients with their urgent orthopedic injuries as well as other illnesses. Denyse chose to become a PA because she has a passion for helping others. She assures her patients that even on the worst of days, she can be of assistance.

Denyse went to Midwestern University in Glendale, AZ, for her PA studies and received her master’s degree with a focus on bio-ethics. She studied molecular, cellular, and developmental biology at CU Boulder. After graduation she worked 3 years in a lab studying inflammation and biological processes of the lung at National Jewish Health.

Denyse enjoys spending time with her family and friends, hiking with her fur babies, and going to concerts and sporting events. She is a true Coloradan and loves to watch the Buffs, Broncos, and Rockies.

Hannah Ney, PA-C

Physician Associate Hannah Ney has spent her PA career in urgent care settings. In addition to her stateside medical work, she has medical volunteer experience in South Africa and Sri Lanka. Hannah is passionate helping all types of patients from all different backgrounds. She emphasizes taking time with each patient and providing individualistic care that fits each patient’s needs.

Hannah attended PA school in Miami, Florida, and St. Croix, U.S. Virgin Islands. While living and experiencing “island life,” she was able to establish a very hands-on and in-depth clinical experience. In addition to her PA degree, Hannah also has bachelor’s degrees in psychology and physiology, allowing for a background of physical and mental health.

As a Colorado native, when not in the office, Hannah can be found doing anything outdoors, including volleyball, mountain biking, and snowboarding.

Patient Review

Kathy E., 5 stars on Google

“This urgent care was awesome. Great service and staff. Very knowledgeable PA [Hannah] and didn’t feel like I was even at urgent care. Highly recommend this care facility. Awesome service!!!”

Iris Kang, NP-C

Nurse Practitioner Iris Kang has 26 years of nursing experience with most of that time spent in the emergency department. She is passionate about helping her patients improve their overall health outcome as well as their understanding and access to healthcare in general. She completed her Master’s degree in Family Practice Nursing at Regis University in Denver.

Iris enjoys traveling, horseback riding, Vespa scooters, hiking, camping, and she is a competitive Irish step dancer. She was active duty Air Force for 10 years and was stationed in Northern and Southern California and overseas in Germany. She loves to read, watch movies, try new restaurants, and visit new places.

Katherine Olliff, APRN-C

Advanced Practice Registered Nurse Katherine Olliff has 6 years of experience in OBGYN and prior to that she worked for 5 years as an ICU nurse. She enjoys the fast pace in urgent care and the ability to make a difference when someone is acutely ill or injured.

Katherine attended Jacksonville University for her bachelor of science in nursing and her family nurse practitioner degrees. Prior to that, she attended CU Boulder and received a master’s degree in German Literature.

She loves all outdoor pursuits in the mountains, especially skiing, hiking, and backpacking. Katherine also enjoys reading (mostly fiction), puzzles, and yoga. She has lived on three continents and loves international travel.

Kathryn Lindsey, FNP-C

Family Nurse Practitioner Kathryn Lindsey has six years of experience as a registered nurse and two years of experience as a nurse practitioner. She earned her undergraduate degree in health science from the James Madison University in Virginia. Kathryn earned her Bachelor of Science in Nursing degree from the Massachusetts College of Pharmacy and Health Sciences. She then attended Simmons University where she graduated with a master’s degree in nursing as a family nurse practitioner.

Kathryn has two little girls – both under the age of 2. She has a dog and two cats. She enjoys being outdoors, hiking, and swimming.

Kristina Johnson, PA-C

Physician Associate Kristina Johnson started practicing urgent care medicine in early 2018. Prior to her career in medicine, she worked in meteorology. She decided to change careers while wintering over at the South Pole, Antarctica. During her career transition, Kristina worked as an ER scribe, senior in-home caregiver, medical receptionist, and a dermatology medical assistant. She enjoys meeting and treating patients of all ages.

Kristina earned a Master of Physician Associate Studies degree from the University of Texas Health Science Center at San Antonio and she has a Bachelor of Science degree from Texas A&M University.

In her free time, Kristina and her husband love to hit the trail with their spirited Corgi.

Patient Review

5 stars on Google

“Kristina Johnson is one of the most amazing doctors I have ever encountered in my life. I am still not feeling 100%, but I already feel better after leaving here than when I showed up. Thank you all for working so hard during these trying times.”

Laura McDonough, PA-C

Physician Associate Laura McDonough spent many years as a physician associate moving around the country with the opportunity to define what she likes best about the profession and finding ways to help patients. She has found that she genuinely likes people and learning how to make them happier and healthier. She discovered a particular love for orthopedics in her travels.

Laura began her career in medicine as a certified nursing assistant. She also worked as a ward clerk in post-operative recovery and on cardiac floors in hospitals. She was also an EKG tech. After graduating from Rosemont College with Bachelor’s Degrees in psychology and mathematics, a minor in bio-chemistry, and a concentration in education, Laura was unsure if she wanted to go to medical school or get a postgraduate degree in neurobiological psychology.

Luckily, during a career counseling session, Laura learned the term “physician associate,” and it changed the rest of her life. She used her educational credits and patient contact hours to pursue her dream of becoming a PA by attending DeSales University. She earned her Master’s Degree in Physician Associate Studies and started her journey of helping those in need.

Laura has a young family that takes up most of her “free time,” but that is just her family’s season of life. Laura and her family love the outdoors, animals, and exploring the different natural wonders around them. They love long hikes, biking, and anything to do with the water. They are committed as a family to do volunteer work and donating to different programs in their communities. They travel frequently with all modes of transport, and love finding little nooks that are off of the well-worn path.

Patient Review

Terrill & Sarah M., 5 stars on Google

“I had the pleasure of meeting super friendly and professional Physician Assistant Laura McDonough who gave me a very thorough exam, explained her findings, and provided a solution. I will be using this office in the future for any urgent care needs.”

Lauren MacDonald, FNP-C

Family Nurse Practitioner Lauren MacDonald worked for over six years as a nurse practitioner in the family practice/primary care setting prior to joining the Advanced Urgent Care team. She also has experience working in urgent care and in workers’ compensation. She has an additional six years of experience as an RN in the emergency department and in family practice/internal medicine. She enjoys the fast-paced environment of urgent care as well as the variety and challenge that it brings. She has a particular passion for fitness and athletics, so she enjoys working with orthopedics/sports-related concerns. She loves her job as a nurse practitioner and is honored to be able to help others with their health in order to live a more healthy and fulfilling life.

Lauren earned her Bachelor’s Degree in Microbiology from the University of New Hampshire. Her Bachelor’s Degree in Nursing is from the Massachusetts College of Pharmacy and Health Sciences. She earned her Masters of Science in Nursing from the University of New Hampshire.

Lauren is a New Hampshire native and she moved to Colorado in the spring of 2020. She loves to travel and explore new places. She also enjoys spending time with her family and friends, spending time at her family’s lake house in Vermont, and visiting her brother and his family in Alaska. She enjoys an active lifestyle and any form of exercise, but her favorites are running, weight lifting, and yoga. She also enjoy hiking and snowboarding. She loves to cook and try new recipes. She loves all kinds of music and going to concerts as well as enjoying a Broadway show or a ballet. She has an adopted kitten named Ella.

Luis Elortondo, PA-C

Physician Associate Luis Elortondo attended Physician Associate School at Nova Southeastern University in Fort Myers, Florida. Luis’ initial exposure to medicine came when he shadowed in an emergency department. This led to him working as a scribe for 3 years while he earned his undergraduate degree.

Luis worked in the emergency department his first year as a physician associate. He has remained passionate about acute care since then. He also has three years of experience working in interventional pain management and neurology. He is happy to be returning to the acute care setting with Advanced Urgent Care.

Luis was born and raised in Argentina. He and his family moved to the United States when he was 14 years old. Luis enjoys playing disc golf and volleyball, woodworking, and hiking with his wife. He plans on working toward getting his pilot license soon.

Patient Review

Carolyn N., 5 stars on Google

“Luis treated me better than family. He took excellent care of me. He is hands down the ‘Best of the Best.’ I am so very blessed to have been under his care.”

Luisa Delima, PA-C

Physician Associate Luisa Delima attended Physician Associate School at Barry University in Miami Shores, Florida. Her undergraduate degree is in exercise science from Florida Atlantic University.

Luisa worked at an urgent care in Florida for one year prior to moving to Colorado. She also has experience in orthopedic surgery.

Luisa moved to Colorado for the mountains and friends. She has two dogs and enjoys biking, going to concerts, and trying new foods.

Nikki Zaobidny, PA-C

Physician Associate Nikki Zaobidny’s interest in urgent care developed over the last two years while she was working at a private practice in Pueblo. She enjoys the variety each day brings, thinking on her feet, and being a listening ear for her patients when they need it most.

Nikki received her physician associate degree from A.T. Still University in Arizona. She attended Colorado State University in Fort Collins for her undergraduate studies in health and exercise science. Prior to PA school, she worked as a rehabilitation aide at Medical Center of the Rockies and as a nursing assistant in end-of-life care.

In her free time she enjoys hiking, reading, skiing, running, and going on walks with her fiancé and their 2 dogs. They have a Corgi and a Cavalier King Charles Spaniel. She loves to travel and scuba dive- her favorite destination thus far has been Belize. The newest hobby she is trying to take on is golf!

Patient Review

5 stars on Google

“I want to say thank you to nurse Nickie Zaobidny. My son had a very infected cyst. She was so kind and professional. It’s rare to find a health care provider that actually cares. She was wonderful to my son and myself. He is healing thanks to the staff that we dealt with at Advanced Urgent Care. Thank you so very much for the care.”

Qing Xu, NP-C

Nurse Practitioner Qing Xu has over 30 years of experience in the medical field. She began her medical career in China working in hospitals and later immigrated to the U.S. for medical research projects. She missed working with patients, so she started working as an MA, histologist, and nurse. Qing has been a nurse practitioner since 2018.

Qing earned her first college degree in China. She graduated from an adult-geriatric nurse practitioner program at Florida International University. She then earned her post-master FNP certificate at the University of Cincinnati.

Qing loves animals and enjoys traveling. She enjoys hiking in the mountains. She and her husband have three lovely dogs.

Sarah Kleinschmidt, PA-C

Physician Associate Sarah Kleinschmidt earned her physician associate studies degree from Wichita State University. Her bachelor of science in nutritional science was earned at Kansas State University.

Patient Review

Jessica G., 5 stars on Google

“Sarah K, the PA-C working when I went in, is AMAZING! If everyone in the medical field had her care, compassion, and bedside manner it would make a world of difference in the medical field.”