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Carmen Gnatenco M.D., S.C.

Internal Medicine Physician in Oak Lawn, IL · enumerated 2008 · authorized official Julian Gnatenco, Billing Manager.

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

National Provider Identifier

1871750711

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Registry record

Entity type Organization (Type 2)
Legal business name Carmen Gnatenco M.D., S.C.
Practice address 4938 W 95th St, Oak Lawn, IL, 60453
Phone (708) 425-4662
Fax (708) 452-4692
Enumeration date May 19, 2008
Last updated in NPPES Aug 24, 2020

Taxonomy & classification

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians Primary

Authorized official

Name Julian Gnatenco
Title Billing Manager
Phone (773) 742-8926

Other identifiers

Identifier Type State Issuer
036115290 Medicaid IL -
1639587 Other IL BCBS
P00692896 Other IL RAILROAD MEDICARE

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

Who is the authorized official for Carmen Gnatenco M.D., S.C.?
NPPES lists Julian Gnatenco (Billing Manager) as the authorized official for this organization.
What is the NPI number for Carmen Gnatenco M.D., S.C.?
The NPI for Carmen Gnatenco M.D., S.C. is 1871750711, a Type 2 (organization) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2020-08-24.