Active NPI
William Ritchie Mackenzie, M.D.
- Infectious Disease Physician
- Mather, CA
National Provider Identifier
1073561601
On this page
Key facts
NPPES NPI Registry- Primary specialty
- Infectious Disease Physician
- License
- G59633
- Practice address
- 10535 Hospital Way
Mather, CA 95655-4200 - Phone
- (916) 843-7107
- NPI assigned
- May 5, 2006
- Sex
- Male
- Sole proprietor
- No
NPPES NPI Registry
Registry information is reported by the provider to CMS and is not verified. About this source
Specialties & licenses 1
| Specialty (taxonomy) | Code | License | State | Primary |
|---|---|---|---|---|
| Infectious Disease Physician | 207RI0200X | G59633 | CA | Primary |
Addresses
Primary practice location
10535 Hospital Way
Mather, CA 95655-4200
Mailing address
380 World Way
Box N-19
Los Angeles, CA 90045-5800
Phone (310) 215-2365
Medicare participation
Medicare enrollment files- Medicare fee-for-service enrollment
- Not listed in the public Medicare enrollment file
National Provider Directory
National Provider Directory- Medicare enrollment (NPD)
- Not enrolled
- Credentials
- Doctor of Medicine
State licenses
| License | State | Type | Specialty |
|---|---|---|---|
| G59633 | CA | MD | Infectious Disease Physician |
NPI Registry JSON
The complete NPPES record for this NPI in the NPI Registry API format.
{
"created_epoch": "1146787200000",
"enumeration_type": "NPI-1",
"last_updated_epoch": "1783900800000",
"number": "1073561601",
"addresses": [
{
"country_code": "US",
"country_name": "United States",
"address_purpose": "MAILING",
"address_type": "DOM",
"address_1": "380 WORLD WAY",
"address_2": "BOX N-19",
"city": "LOS ANGELES",
"state": "CA",
"postal_code": "900455800",
"telephone_number": "310-215-2365",
"fax_number": "310-215-2285"
},
{
"country_code": "US",
"country_name": "United States",
"address_purpose": "LOCATION",
"address_type": "DOM",
"address_1": "10535 HOSPITAL WAY",
"city": "MATHER",
"state": "CA",
"postal_code": "956554200",
"telephone_number": "916-843-7107"
}
],
"practiceLocations": [],
"basic": {
"last_name": "MACKENZIE",
"first_name": "WILLIAM",
"middle_name": "RITCHIE",
"name_prefix": "Dr.",
"credential": "M.D.",
"sole_proprietor": "NO",
"sex": "M",
"enumeration_date": "2006-05-05",
"last_updated": "2026-07-13",
"status": "A"
},
"taxonomies": [
{
"code": "207RI0200X",
"taxonomy_group": "",
"desc": "Internal Medicine, Infectious Disease",
"state": "CA",
"license": "G59633",
"primary": true
}
],
"identifiers": [],
"endpoints": [],
"other_names": []
}Other providers in Mather, CA
Sources for this page
- NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jul 13, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
- National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.