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Marianna W. Horn, MD

Pediatric Hematology & Oncology Physician in Washington, DC · enumerated 2006.

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

National Provider Identifier

1083692057

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Registry record

Entity type Individual (Type 1)
Name Marianna W. Horn
Credential MD
Sex Female
Practice address 700 2nd St Ne, Washington, DC, 20002
Phone (202) 346-3000
Enumeration date Jan 9, 2006
Last updated in NPPES Jan 11, 2013

Taxonomy & licenses

2080P0207X Pediatric Hematology & Oncology Physician Allopathic & Osteopathic Physicians · License 0101054079 (VA) 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
006718159 Medicaid VA -

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

Where does Marianna Horn practice?
The practice location on file with NPPES is in Washington, DC. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Marianna Horn?
The National Provider Identifier (NPI) for Marianna Horn is 1083692057, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2013-01-11.