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Chicago Arthritis LLC

Rheumatology Physician in Chicago, IL · enumerated 2016 · authorized official Siddharth Tambar, M.D.

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

National Provider Identifier

1477915221

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Registry record

Entity type Organization (Type 2)
Legal business name Chicago Arthritis LLC
Practice address 618 W Fulton St, Chicago, IL, 60661
Phone (773) 348-7171
Fax (773) 348-7414
Enumeration date Mar 22, 2016
Last updated in NPPES Aug 28, 2024

Taxonomy & classification

207RR0500X Rheumatology Physician Allopathic & Osteopathic Physicians · License 036111655 (IL) Primary

Authorized official

Name Siddharth Tambar
Title M.D
Phone (773) 348-7171

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

How current is this record?
Data comes from the CMS NPPES public dissemination file; this record was last updated in NPPES on 2024-08-28. Verify at npiregistry.cms.hhs.gov.
Where is Chicago Arthritis LLC located?
The practice location on file with NPPES is in Chicago, IL.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2024-08-28.