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Alexander Donald Pyden, MD

Anatomic Pathology & Clinical Pathology Physician in Burlington, MA · enumerated 2015.

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

National Provider Identifier

1548650971

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Registry record

Entity type Individual (Type 1)
Name Alexander Donald Pyden
Credential MD
Sex Male
Practice address 41 Mall Road Lahey Hospital and Medical Center, Burlington, MA, 01805
Phone (781) 744-8000
Enumeration date Jan 22, 2015
Last updated in NPPES Jun 9, 2021

Taxonomy & licenses

390200000X Student in an Organized Health Care Education/Training Program Student, Health Care Secondary
207ZP0102X Anatomic Pathology & Clinical Pathology Physician Allopathic & Osteopathic Physicians · License 286257 (MA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

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 Alexander Pyden?
Alexander Pyden is registered in NPPES with the primary taxonomy of Anatomic Pathology & Clinical Pathology 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 2021-06-09.