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Steffen Sum

DVM, ECVIM
Steffen Sum
Medical Director
Internal Medicine
Steffen Sum

At a Glance

Board Certified:

Internal Medicine

Dr. Steffen Sum comes from an extensive background in teaching beyond academia, and instilling the best of medical practice to his students. After his intensive veterinary studies at Ludwig-Maximilians-Universität in Munich, his focus included extensive work and ongoing training in urology, diagnostic services, hemodialysis, infectious disease, advanced imaging and endoscopy. He published numerous works on these topics as well as providing high level training and mentoring at University of Georgia for 8 years.

Dr. Sum now provides Small Animal Internal Medicine to our patients at VCA Highlands Ranch Specialty & Emergency Center, offering diagnostic services in ultrasound and endoscopy as well as treating our hospitalized intensive care dogs and cats. He also provides internal medicine consultations on an out-patient basis with complicated medical cases such as advanced diabetes, renal failure and other hormonal ailments.

Having grown up in the Black Forest of Germany, he has now completely fallen in love with our Colorado outdoors, where he hikes as well as enjoying horseback riding and his motorcycle rides.

As Medical Director, Dr. Sum serves to assure that the highest veterinary medical care is followed throughout the entire VCA Highlands Ranch team.

Our Internal Medicine Team

Staff Veterinarian
See our departments

Internal Medicine

Internal medicine is practiced by internists, or doctors that specialize in the treatment, diagnosis and prevention of most diseases that are not surgical in nature. Thus, as in human medicine, internists can be called a "doctor's doctor" due to the fact that they tend to specialize in patients with conditions that are more difficult to treat and/or diagnose. Internists are also often trained to use advanced diagnostic and therapeutic procedures that may not be available at regular veterinarians. These include rhinoscopy, bronchoscopy, gastroduodenoscopy, colonoscopy, vaginoscopy, cystoscopy; thoracic and abdominal ultrasounds, computed tomography (CT or CAT) scans, stent placement and management including tracheal stents, urethral and uretheral stents, cystoscopic-guided removal of bladder stones, respiratory testing, blood and infectious disease workups, feeding tube placement, obtaining biopsies and cytology samples of many tissues, joint taps, bone marrow aspiration and core biopsy, CSF taps, and many more advanced laboratory testing.

The Role of an Internal Medicine Specialist

Your pet's condition may be more complicated than your regular veterinarian feels comfortable diagnosing and treating. Furthermore, your pet may have multiple underlying conditions that have conflicting treatments. This kind of patient will benefit from a consultation with an internist.

From animals that don't seem to be able to stop having accidents in the house to animals with severe heart disease that are oxygen dependent, and internist has the experience and knowledge necessary to deliver the absolute best care available. Some of the advanced diagnostics available can change a situation from one where we don't know what is causing a dog to stop eating and act tired to having the information we need to begin immediate treatment for a speedy and full recovery.

An internist is NOT a replacement for your regular veterinarian, but a power complement that works closely with your pet's family doctor to ensure that they receive the absolute best medical care that is available today.

VCA Highlands Ranch Animal Specialty & Emergency Center's department of internal medicine is lead by Dr. Steffen Sum. His focus includes extensive work and ongoing training in urology, diagnostic services, hemodialysis, infectious disease, advanced imaging and endoscopy.

VCA Highlands Ranch Animal Specialty & Emergency Center

5640 County Line Place Suite 1

Highlands Ranch, CO 80126

Main: 303-740-9595

Hospital Hours:

    Mon-Fri: 7:00 am - 6:00 pm

    Sat-Sun: Closed

Hours Information:

Extended Hours: Monday-Friday, 6:00 pm-10:00 pm, for patient monitoring and discharges

Specialty DVM Appts: Call (303) 740-9595

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