Alexander Louis Kostrinsky-Thomas, DO

Primary specialty

Hospitalist PhysicianTaxonomy code 208M00000X

License

20A21736 Issued in CA

Practice address

10 Koret Way
San Francisco, CA 94143-2218

Phone

(415) 514-1378

NPI assigned

Apr 9, 2022

Sex

Male

Sole proprietor

No

Registry information is reported by the provider to CMS and is not verified. About this source

Specialties & licenses 2

Addresses

Medicare fee-for-service enrollment

Enrolled in CA

Eligible to order & refer

• Part B services: Yes
• Medical equipment: Yes
• Home health: Yes
• Power mobility devices: Yes
• Hospice: Yes

Green means eligible to order or refer.

Enrollment records 1

Specialty

HospitalistAlso: Internal Medicine

Education

Other, 2022

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

Regents of the University of CaliforniaGroup PAC ID 4284547274, 706 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• UCSF Medical Center Hospital, San Francisco, CA, CCN 050454

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Osteopathy

State licenses

Practice roles

Locations

Interoperability endpoints

• Direct secure messaging: akostrinskythomas425479@direct-ucsfmedicalcenter.org

Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships and National Provider Directory roles.

• Regents of the University of California

  • Internal Medicine Physician
  • San Francisco, CA
  • NPI 1760552343
  Medicare reassignment Care Compare group NPD
• UCSF Medical Group Business Services

  • Internal Medicine Physician
  • San Francisco, CA
  • NPI 1477624104
  Medicare reassignment NPD
• University of California San Francisco

  • Pediatrics Physician
  • San Francisco, CA
  • NPI 1861578973
  Medicare reassignment NPD
• UCSF Medical Group Business Services

  • Health Service Clinic/Center
  • San Francisco, CA
  • NPI 1194115246
  NPD
• University of California San Francisco

  • Community/Retail Pharmacy
  • San Francisco, CA
  • NPI 1659141711
  NPD
• Regents of the University of California

  • Rheumatology Physician
  • San Francisco, CA
  • NPI 1881763597
  NPD (past)
• University of California San Francisco Medical Center

  • General Acute Care Hospital
  • San Francisco, CA
  • NPI 1144325440
  NPD (past)

Hospitals and other facilities this clinician is affiliated with according to Medicare Care Compare.

• University of California, San Francisco

  • General Acute Care Hospital
  • San Francisco, CA
  • NPI 1689772592
  Care Compare affiliation

The complete NPPES record for this NPI in the NPI Registry API format.

{
    "created_epoch": "1649462400000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1749254400000",
    "number": "1700528833",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "751 S BASCOM AVE",
            "city": "SAN JOSE",
            "state": "CA",
            "postal_code": "951282699"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "10 KORET WAY",
            "city": "SAN FRANCISCO",
            "state": "CA",
            "postal_code": "941432218",
            "telephone_number": "415-514-1378"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "751 S Bascom Ave",
            "address_purpose": "LOCATION",
            "city": "San Jose",
            "state": "CA",
            "postal_code": "951282604",
            "country_code": "US",
            "telephone_number": "408-885-5000",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "KOSTRINSKY-THOMAS",
        "first_name": "ALEXANDER",
        "middle_name": "LOUIS",
        "credential": "DO",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2022-04-09",
        "last_updated": "2025-06-07",
        "certification_date": "2025-06-07",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "390200000X",
            "taxonomy_group": "",
            "desc": "Student in an Organized Health Care Education/Training Program",
            "state": null,
            "license": null,
            "primary": false
        },
        {
            "code": "208M00000X",
            "taxonomy_group": "",
            "desc": "Hospitalist",
            "state": "CA",
            "license": "20A21736",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Felicitas Koster, D.O.
• Hillary Koster, MS
• Skylar Marie Kostick, PA-C
• Vera Kostko
• Katina K Kostoulas, PHD
• Martin Kosztowski, M.D.
• Sarah Koszyk, M.A., R.D.
• Aparna Kota, MD, MPH
• Sharonlee Kotabe, PHARMD
• Shyamsundar Kotagal, PSY.D.

• Hospitalist Physician in San Francisco, CA
• Providers in San Francisco, CA by specialty
• Hospitalist Physician in California

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jun 7, 2025; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments; Order and Referring.
• Medicare Care Compare (CMS): clinician profile, group practices, facility affiliations, MIPS scores and star ratings.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.