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Fortress Corporation

Diagnostic Radiology Physician in Knoxville, TN · enumerated 2006 · authorized official Leslie Irwin, Vice President-Fortress Corp.

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

National Provider Identifier

1558338798

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Registry record

Entity type Organization (Type 2)
Legal business name Fortress Corporation
Other name <Unavail>
Practice address 210 Fort Sanders West Blvd, Bldg 3 Suite 100, Knoxville, TN, 37922
Phone (865) 531-5400
Fax (865) 531-5043
Enumeration date Mar 7, 2006
Last updated in NPPES Jul 21, 2022

Taxonomy & classification

2085R0202X Diagnostic Radiology Physician Allopathic & Osteopathic Physicians Primary

Authorized official

Name Leslie Irwin
Title Vice President-Fortress Corp
Phone (865) 531-5248

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

What is the NPI number for Fortress Corporation?
The NPI for Fortress Corporation is 1558338798, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Fortress Corporation?
NPPES lists Leslie Irwin (Vice President-Fortress Corp) as the authorized official for this organization.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2022-07-21.