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Dean G Sienko, MD

Public Health & General Preventive Medicine Physician in Lansing, MI · enumerated 2006.

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

National Provider Identifier

1831288398

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Registry record

Entity type Individual (Type 1)
Name Dean G Sienko
Credential MD
Sex Male
Practice address 5303 S Cedar St, Lansing, MI, 48911
Phone (517) 887-4428
Enumeration date Oct 12, 2006
Last updated in NPPES Jul 27, 2011

Taxonomy & licenses

2083P0901X Public Health & General Preventive Medicine Physician Allopathic & Osteopathic Physicians · License 4301048740 (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
771957141 Medicaid MI -

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.

Read the full guide → Validate an NPI →

Frequently asked questions

What specialty is Dean Sienko?
Dean Sienko is registered in NPPES with the primary taxonomy of Public Health & General Preventive Medicine Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
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.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-07-27.