DR. VIVIEN AN NGUYEN M.D.
NPI 1154586659
Pediatrics - Pediatric Gastroenterology in Walnut Creek, CA

Q: What is Vivien Nguyen's NPI number?

The NPI number for Vivien Nguyen is 1154586659. It was assigned to this individual provider in the NPPES registry on July 23, 2008.

Q: What is Vivien Nguyen's specialty?

The primary specialty registered for this NPI is Pediatrics, specializing in Pediatric Gastroenterology, with taxonomy code 2080P0206X.

Q: When was this NPI record last updated?

The NPPES record for Vivien Nguyen was last updated on December 19, 2017. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since July 23, 2008PECOS Enrolled

106 LA CASA VIA STE 100, WALNUT CREEK, CA 94598(650) 497-8000 Get Directions Write a Review

NPPES record last updated: December 19, 2017. Verified against the NPPES registry weekly; last sync: October 25, 2026.

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About Dr. Vivien An Nguyen M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. VIVIEN AN NGUYEN M.D. (NPI 1154586659) is an individual pediatric gastroenterology provider in Walnut Creek, California, licensed in California (A101918) and active in the NPI registry since July 2008. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1154586659

Entity TypeIndividualFemale

Primary Taxonomy2080P0206X

Provider Legal NameDR. VIVIEN AN NGUYENCredential: M.D.

Location Address106 LA CASA VIA STE 100Walnut Creek, CA 94598-3084

Mailing Address106 La Casa Via Ste 100Walnut Creek, CA 94598-3084 · (650) 497-8000

Phone(650) 497-8000

Sole ProprietorNo

Enumeration DateJuly 23, 2008

Last NPPES UpdateDecember 19, 2017

✔ NPI 1154586659 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyPediatrics · Pediatric GastroenterologyAllopathic & Osteopathic Physicians

Taxonomy Code2080P0206X

License✔ Licensed in CA · A101918

Definition

A pediatrician who specializes in the diagnosis and treatment of diseases of the digestive systems of infants, children and adolescents. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using lighted scopes to see internal organs.

Also ListedPediatricsTaxonomy 208000000X · License A101918 (CA)

106 LA CASA VIA STE 100, Walnut Creek, CA 94598

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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Vivien An Nguyen M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

Medicare enrollment records show Vivien Nguyen reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

University Of California San Francisco

25 mi

Surgery

400 PARNASSUS AVE, MCB 300
San Francisco, CA 94143

Reassigned Medicare billing, California enrollment
5,645 clinicians in this Medicare group

NPI 1346329380 (415) 353-2161

Ucsf Pediatrics Associates

25 mi

Pediatrics

505 PARNASSUS AVE
San Francisco, CA 94143

Reassigned Medicare billing, California enrollment
1,159 clinicians in this Medicare group

NPI 1376614016 (415) 353-2000

Lpch Medical Group Div Of Lucile

34 mi

Children

725 WELCH RD
Palo Alto, CA 94304

Reassigned Medicare billing, California enrollment
3,617 clinicians in this Medicare group

NPI 1417907940 (650) 498-6762

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94598 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$153.83 typical visit price

range $69.00 – $202.35

Typical copayment $38.45 (range $17.25 – $50.58)

Most-billed visit code 99204

Established Patient

$119.48 typical visit price

range $23.44 – $166.46

Typical copayment $29.87 (range $5.86 – $41.61)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Referred Medical Equipment & Supplies CMS DME claims 2

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Enteral feeding supply kit; pump fed, per day, includes but not limited to feeding/flushing syringe, administration set tubing, dressings, tape B4035

Other-Enteral and Parenteral · category OB006N

3 suppliers21 claims630 services$5.19 avg. paid by Medicare

Enteral formula, nutritionally complete with intact nutrients, includes proteins, fats, carbohydrates, vitamins and minerals, may include fiber, administered through an enteral feeding tube, 100 calories = 1 unit B4150

Other-Enteral and Parenteral · category OB006N

2 suppliers19 claims7,714 services$0.34 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 11

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

ERICA CHRISTINE BENNETT MD

Otolaryngology