
Accepting patients
Affiliated with a Castle Connolly Top Hospital
Who is Dr. Derleth, Gastroenterologist in Seattle, WA?
Dr. Mark Derleth, MD is a Gastroenterologist, who primarily practices in Seattle, WA with 2 additional practice locations. He is board certified. Dr. Derleth graduated from Boston University School of Medicine and completed his residency at University of Washington, Dept of Radiation Oncology. Dr. Derleth is fluent in English and Spanish, and is currently seeing new patients. Dr. Derleth’s practice accepts Kaiser Permanente, Medicare and other major insurance plans. To book an appointment or to confirm insurance options, please call Dr. Derleth’s office.
Where did Dr. Derleth go to medical school and complete their residency?
Fellowship: University of Washington, Dept of Radiation Oncology
Residency: University of Washington, Dept of Radiation Oncology
Medical School: Boston University School of Medicine
Is Dr. Derleth board certified as a Gastroenterologist?
Yes, Dr. Mark Derleth, MD is board certified by the American Board of Internal Medicine , American Board of Internal Medicine since 2009
What languages does Dr. Derleth speak?
Dr. Derleth and their clinical team can communicate with patients in the following languages:
English
Spanish
What conditions does a Gastroenterologist like Dr. Derleth typically treat?
As a Gastroenterologist, Dr. Derleth diagnoses, treats, and manages a wide range of conditions. This condition information is derived from anonymized insurance claims and highlights the medical conditions most commonly treated by Dr. Derleth. It provides insight into the doctor’s areas of experience and expertise based on real-world patient encounters from the past two years, updated quarterly. Learn more about our claims-based healthcare methodology.
Also known as:
- Colon Cancer Screening
- Health Screening
- Colorectal Cancer Screening (PDQ®)
- Screening Tests to Detect Colorectal Cancer and Polyps
- Tests to Detect Colorectal Cancer and Polyps
- Colorectal Cancer Screening
- Colonoscopy Screening
- Bowel Cancer Screening
ICD-10 Codes:
- Z1211: Encounter for screening for malignant neoplasm of colon
Also known as:
- Acid Reflux
- GERD
- Acid Reflux (GER & GERD) in Adults
- Acid Reflux (GER & GERD) in Children
- Acid Reflux (GER & GERD) in Infants
- Gastroesophageal Reflux
- Heartburn
- Indigestion
ICD-10 Codes:
- K219: Gastro-esophageal reflux disease without esophagitis
Also known as:
- Dark, Tarry Stools (Melena)
- Gastrointestinal Bleeding
- Melena
- Black Stools
- Upper GI Bleed Signs
ICD-10 Codes:
- K921: Melena
Also known as:
- Non-Infectious Gastroenteritis and Colitis
- Digestive Disease
- Inflammation of Stomach and Intestines
- Non-Bacterial Colitis
- Gut Inflammation
ICD-10 Codes:
- K529: Noninfective gastroenteritis and colitis, unspecified
Also known as:
- Gastrostomy
- Ostomy
- Feeding Tube Opening
- Stomach Stoma
- G-tube
ICD-10 Codes:
- Z931: Gastrostomy status
What procedures does a Gastroenterologist like Dr. Derleth typically perform?
As a Gastroenterologist, Dr. Derleth performs a variety of medical procedures. This procedure information is derived from anonymized insurance claims and highlights the medical procedures most commonly performed by Dr. Derleth. It provides insight into the doctor’s areas of experience and expertise based on real-world patient encounters from the past two years, updated quarterly. Learn more about our claims-based healthcare methodology.
Also known as:
- Colonoscopy with Biopsy
- Colonoscopy with Polyp Removal
- Diagnostic Colonoscopy with Biopsy
- Colonoscopy
- Colorectal Cancer Screening Tests
- Flexible Colonoscopy
- Colon Biopsy
- Large Intestine Scope
- Colorectal Cancer Screening
- Flexible Colonoscopy with Polypectomy
- Colon Polyp Removal
- Colorectal Lesion Excision
- Colon Exam with Biopsy
- Lower Endoscopy
- Colon Cancer Screening
CPT Codes:
- 45380: Colonoscopy, flexible; with biopsy, single or multiple
- 45385: Colonoscopy, flexible; with removal of tumor(s), polyp(s), or other lesion(s) by snare technique
- 45378: Colonoscopy, flexible; diagnostic, including collection of specimen(s) by brushing or washing, when performed (separate procedure)
Also known as:
- Upper Endoscopy with Biopsy
- Biopsy
- Endoscopy
- EGD with Biopsy
- Gastroscopy with Biopsy
- Esophagogastroduodenoscopy with Biopsy
CPT Codes:
- 43239: Esophagogastroduodenoscopy, flexible, transoral; with biopsy, single or multiple
Also known as:
- Diagnostic Upper Endoscopy with Biopsy
- EGD with Esophageal Balloon Dilation
- Colonoscopy with Injections
- Colonoscopy
- Colorectal Cancer Screening Tests
- EGD with Biopsy
- Esophagogastroduodenoscopy
- Upper GI Endoscopy
- Stomach Scope with Sample
- Upper Endoscopy with Esophageal Dilation
- Flexible Esophagoscopy with Balloon
- EGD with Balloon Widening
- Flexible Colonoscopy with Injection
- Colon Scope with Medication
- Therapeutic Colonoscopy
CPT Codes:
- 43235: Esophagogastroduodenoscopy, flexible, transoral; diagnostic, including collection of specimen(s) by brushing or washing, when performed (separate procedure)
- 43249: Esophagogastroduodenoscopy, flexible, transoral; with transendoscopic balloon dilation of esophagus (less than 30 mm diameter)
- 45381: Colonoscopy, flexible; with directed submucosal injection(s), any substance
Does Dr. Derleth accept my insurance?
Dr. Derleth accepts most major insurance plans. Important: Please call our office at before your appointment to verify that your specific plan and network are accepted.
What insurance plans does Dr. Derleth accept in Seattle, WA?
Dr. Derleth in Seattle, WA accepts plans from many carriers. While this list is updated regularly, it is not a guarantee of coverage.
Top Insurances
Blue Cross Blue Shield Association
Cambia Health Solutions
CVS Health (formerly Aetna)
Elevance Health Inc. (formerly Anthem)
Medicare
Molina Healthcare
Premera Blue Cross
State of Washington
UnitedHealth Group
Unknown
View All Insurances
Where is Dr. Derleth's office located?
What is Dr. Derleth's NPI number?An National Provider Identifier (NPI) is a unique ID number that identifies doctors and healthcare providers nationwide.
Dr. Derleth's National Provider Identifier (NPI) number is 1356457063.
What common questions do patients ask about Dr. Derleth?
Here are answers to patients Frequently Asked Questions (FAQ’s) about Dr. Derleth
What is Dr. Mark Derleth's specialty?
Dr. Derleth is a Gastroenterologist near Seattle, WA.
What does a Gastroenterologist do?
An internist focused on diagnosing and treating disorders of the digestive system, encompassing the stomach, intestines, liver, and gallbladder. This specialist manages conditions like abdominal pain, ulcers, diarrhea, cancer, and jaundice, and performs intricate diagnostic and therapeutic procedures using endoscopes to examine internal organs.
Is this Dr. Mark Derleth affiliated with a ranked Castle Connolly Top Hospital?
Yes, Dr. Derleth is affiliated with Uw Medical Center - Montlake, Confluence Health Hospital - Central Campus which are a Castle Connolly Top Hospitals. Castle Connolly Top Hospitals are healthcare institutions recognized for their excellence in specific medical procedures and overall patient care. They are identified through a rigorous peer nomination process, evaluating factors like patient outcomes, quality of care, and expertise. The list recognizes hospitals that excel in 20 or more specific medical procedures, representing the top 25% nationwide. Castle Connolly Top Hospitals
When to see a Gastroenterologist?: Guides for symptoms, conditions, and treatments
Understand your symptoms and know when it’s time to see a Gastroenterologist. Explore insights from trusted medical experts on EverydayHealth.com, where you'll find the most relevant content and helpful condition guides for up-to date information about symptoms, causes, diagnosis, treatment and more. See all our health guides to find trusted information on medical conditions from our experts at Everyday Health.
Is Mark Derleth accepting new patients in Seattle, WA?
Yes, Dr. Mark Derleth is accepting new patients at this time.
Does Dr. Mark Derleth offer online booking?
Please contact Dr. Derleth's office for information about online booking, telehealth, or to schedule an appointment.
How can I make an appointment with Mark Derleth?
Please contact Dr. Derleth's office for information regarding telehealth appointment availability or for scheduling assistance.
Which board certifications does Dr. Mark Derleth have?
Dr. Mark Derleth is certified by the American Board of Internal Medicine.
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