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

Guat Sia Sy Jr., MD

Colon & Rectal Surgery Physician in Dearborn, MI · enumerated 2005.

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

National Provider Identifier

1114929791

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Registry record

Entity type Individual (Type 1)

Name Guat Sia Sy Jr.

Credential MD

Sex Male

Practice address Dearborn, MI, 48126

Phone (313) 271-2990

Fax (313) 271-1698

Enumeration date Aug 12, 2005

Last updated in NPPES Nov 2, 2009

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

Taxonomy & licenses

208600000X Surgery Physician Allopathic & Osteopathic Physicians · License 4301040071 (MI) Secondary

208C00000X Colon & Rectal Surgery Physician Allopathic & Osteopathic Physicians · License 4301040071 (MI) Primary

MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier	Type	State	Issuer
1114929791	Medicaid	MI	-
020010746	Other	MI	RAILROAD MEDICARE
2929938-10	Medicaid	MI	-
B45647	Other	MI	HAP
0208269691	Other	MI	BCBS PIN
4079900	Other	MI	AETNA
P00753351	Other	MI	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

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 Guat Sy?

Guat Sy is registered in NPPES with the primary taxonomy of Colon & Rectal Surgery Physician. 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 2009-11-02.