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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Clay F Istre, PA-C

Physician Assistant in San Antonio, TX · enumerated 2010.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1811214521

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Registry record

Entity type Individual (Type 1)
Name Clay F Istre
Credential PA-C
Sex Male
Practice address San Antonio, TX, 78248
Phone (210) 493-4357
Fax (210) 493-4355
Enumeration date Apr 21, 2010
Last updated in NPPES Jun 26, 2015

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

363A00000X Physician Assistant Physician Assistants & Advanced Practice Nursing Providers · License PA09534 (TX) Primary

Other identifiers

Identifier Type State Issuer
343919203 Medicaid TX -
343919201 Medicaid TX -
343919202 Medicaid TX -

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Clay Istre?
Clay Istre is registered in NPPES with the primary taxonomy of Physician Assistant. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2015-06-26.