CHPG Northwest Gastroenterology Specialists

Specialty: Gastroenterology
80 Health Park Dr
STE 270
LOUISVILLE, CO, 80027-9584
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Welcome to CHPG Gastroenterology Avista. We believe in providing you the very best treatment and compassion to help keep digestive disorders from interrupting your life. No matter if you are experiencing ongoing gastrointestinal disease or a simple stomach condition, our highly trained providers are ready to help you every step of the way.

Our physicians and clinicians are considered leaders in their field. Our multi-disciplinary conference team meets weekly to discuss patient cases. Together they create unique care plans that are tailored to be patient specific. Ensuring each patient will experience our shared philosophy of whole person care. Whole person care means:

  • Ease of access
  • Patient-centric navigation
  • Reduction of unnecessary visits and treatments
  • Outcomes and evidence-based care plans
  • Partnered goal setting with quality of life top of mind
  • Minimally invasive and revolutionary treatment options
  • State-of-the-art equipment and technology

Our Services

Our highly trained experts provide treatment to all of our adult and senior patients who visit us here at CHPG Gastroenterology Avista. You can depend on them to treat many conditions affecting the GI tract, including the stomach, intestines, liver, esophagus, and pancreas.

For many patients, their discomfort can be attributed to routine concerns that are easily treated. However, it is important to understand what is really happening with your health. To properly understand the underlying conditions, additional diagnostic testing may be necessary. Routine screenings help to catch diseases and disorders early, creating better outcomes for our patients, as well as reducing unnecessary treatments. Once the symptoms have been identified, it is easier to select the screening technology that will be least invasive and most effective in determining a specific condition and tailored treatment plan.

Our experts can recommend an individually tailored treatment plan for digestive and gastrointestinal issues.

Cancer Screening

CHPG Northwest Gastroenterology Specialists

Cancer Screening

Because early detection of colon cancer can save lives, our physicians perform a variety of screenings including colonoscopies, which can identify and remove polyps before they become cancerous.

  • EGD - diagnostic and therapeutic
  • Halo/Radiofrequency ablation for Barrett's EMR/endoscopic mucosal resection
  • Colonoscopy - diagnostic and therapeutic
  • ERCP/endoscopic retrograde cholangiopancreatography with therapeutic interventions

Learn More at ACS

GI Tests & Procedures

CHPG Northwest Gastroenterology Specialists

GI Tests & Procedures

Working closely with our nurse navigator and our dedicated gastrointestinal specialists we will build an individualized plan our patients can trust. When your plan calls for surgery we offer a wide range of approaches from minimally invasive to more complex surgery.

Procedures and services we offer:

  • Anorectal manometry testing
  • Bravo pH capsule
  • Colonoscopy
  • Endoscopic retrograde cholangiopancreatography (ERCP)
  • Endoscopy
  • Endoscopy with dilation
  • Endoscopy with small bowel biopsy
  • Enteroscopy
  • Flexible sigmoidoscopy
  • Hemorrhoid banding
  • High resolution esophageal monometry
  • Hydrogen breath test
  • Lactose breath test
  • PEG (Feeding Tube) placement
  • 24-Hour impedance/pH study

Conditions We Treat

  • Achalasia (swallowing problem)
  • Acid reflux or heartburn
  • Acute pancreatitis
  • Barrett's esophagus
  • Celiac disease
  • Crohn’s disease
  • Chronic pancreatitis
  • Collagenous colitis
  • Constipation
  • Diverticulitis
  • Fatty liver
  • Gallstones
  • GERD (gastroesophageal reflux disease)
  • Hemorrhoids
  • Hiatal hernia
  • Incontinence
  • Infectious colitis
  • Inflammatory bowel disease
  • Irritable bowel syndrome (IBS)
  • Ischemic colitis
  • Lactose intolerance
  • Lymphocytic colitis
  • Non-celiac gluten sensitivity
  • Pancreatic pseudocysts
  • Small bowel bacterial overgrowth
  • Ulcerative colitis
  • Ulcers


Ariana Greenwood
Ariana Greenwood, MD
Gastroenterology, Internal Medicine
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Scott Hallgren, DO
Scott Hallgren, DO
Gastroenterology, Internal Medicine
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Marissa Moritz-Guzik, PA-C
Marissa Moritz-Guzik, PA-C
Physician Assistant, Gastroenterology
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STE 300
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Fax: 720-455-3791
Centura Gastroenterology Littleton
7780 S Broadway
Ste 260
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Fax: 303-347-5361
Centura Gastroenterology Parker
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Fax: 303-925-4721
CHPG Northwest Gastroenterology Specialists
80 Health Park Dr
STE 270
LOUISVILLE, CO, 80027-9584
Centura Gastroenterology Porter
STE 410
Denver, CO, 80210-5847
Fax: 303-260-2741
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