Exhaled Nitric Oxide

An exhaled nitric oxide test.

An exhaled nitric oxide test can help with the diagnosis and treatment of asthma. It measures the level of nitric oxide gas in an exhaled sample of your breath. This sample is collected by having you breathe into the mouthpiece of a machine that performs the measurement.

Patch Testing

Patch Testing: Allergic contact dermatitis is tested by a procedure called patch testing

Many people believe that if they have not been exposed to a new contact allergen, then an allergy is unlikely, but surprisingly, the reverse is true; the more frequently we are exposed to a product, the more likely we are to develop an allergy to one of its ingredients. Therefore, common household items are frequently the cause of allergic contact dermatitis.

Penicillin Allergy Testing

Penicillin Allergy Testing

Ten percent of the population suspects they are allergic to penicillin, when in fact less than 1% actually are allergic. Furthermore, 80% of penicillin allergic individuals appear to lose that allergy after 10 years. Suspecting a penicillin allergy, when there is not really one present, can be harmful and dangerous to an individual. Instead of using penicillin, those patients may receive antibiotics that are not as effective or that have more side effects.

William A. Scott, M.D.

Dr. Scott completed his residency at the University of Colorado Medical Center and a fellowship in allergy and clinical immunology at National Jewish Hospital in Denver. He is a fellow of the American Academy of Allergy, Asthma and Immunology and the American College of Allergy, Asthma and Immunology. Dr. Scott is a Diplomate of the American Board of Allergy and Immunology.

William A. Scott, M.D.

Cathryn E. Schnell

She works closely with Dr. Scott and Dr. Tille to provide the highest quality care to their patients. She earned a Bachelor of Science degree with a major in Kinesiology at the University of Northern Colorado. She then went on to receive her masters degree in physician assistant studies at Midwestern University in Arizona. She has a strong interest in allergies and asthma and enjoys treating both pediatric and adult patients with these conditions. She is a Colorado native and is thrilled to have the opportunity to work, live, and play in the Grand Valley.

Cathryn E. Schnell

David R. Scott, M.D.

Dr. Scott received his medical degree from the University of Colorado School of Medicine. He then completed his residency training and served as chief resident at the Oregon Health Science University in Portland, OR before obtaining subspecialty fellowship training in allergy, asthma and immunology at Scripps Clinic in San Diego, CA. He is a member of the American Academy of Allergy, Asthma and Immunology and the American College of Allergy, Asthma and Immunology. Dr. Scott is a Diplomate of the American Board of Allergy and Immunology.

David R. Scott, MD

Katherine S. Tille, M.D.

Dr. Tille joined the Allergy and Asthma Center of Western Colorado in August of 2018. She completed her medical degree at Saint Louis University School of Medicine. She is a veteran of the United States Air Force, during which time she completed her residency training in Pediatrics through Wright State University, and went on to serve as a Pediatrician for six years. She subsequently completed her fellowship training in allergy, asthma and immunology at Wilford Hall in San Antonio, TX. Dr.

Katherine S. Tille, M.D.

About Us

We are the longest standing Allergy and Asthma Center in western Colorado and the only board certified Allergy & Immunology specialists serving the Grand Valley, Delta and Montrose region.