Lewis Sierra, MD
NPI 1346222023 · Internal Medicine Physician · Fond Du Lac, WI
Lewis Sierra, MD is a Internal Medicine Physician provider in Fond Du Lac, WI (NPI 1346222023).
Provider details
- NPI number
- 1346222023
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 26876 (WI)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
20 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2005-11-17
- Last updated
- 2010-04-09
Frequently asked questions
- What is Lewis Sierra's NPI number?
- Lewis Sierra's National Provider Identifier (NPI) is 1346222023, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Lewis Sierra's specialty?
- Lewis Sierra is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Lewis Sierra located?
- Lewis Sierra's practice location on file with NPPES is 145 N Main St, Fond Du Lac, WI 54935-3423.
- What is Lewis Sierra's phone number?
- The practice phone number listed in the NPPES registry for Lewis Sierra is (920) 926-8492.
- Is Lewis Sierra's NPI active?
- Yes — Lewis Sierra's NPI (1346222023) is active in the NPPES registry as of the last update on 2010-04-09.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.