Individual provider

Elsa Hartwick, M.D.

Internal Medicine Physician Nephrology Physician Medicare enrolled

Elsa Hartwick, M.D. is an Internal Medicine Physician in Los Angeles, CA, registered under NPI 1558375022. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.

Getting there

The practice address on file is 1414 S GRAND AVE STE 380, Los Angeles, CA 90015. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

1414 S GRAND AVE STE 380, Los Angeles, CA 90015 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
A065743 CA Internal Medicine Physician primary
A65743 CA Nephrology Physician

This provider holds licence A065743 issued in CA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Internal Medicine
PAC ID
7810025525
Enrollment ID
I20101103000052

Medicare enrolment is recorded as approved under the provider type Practitioner - Internal Medicine. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.

What Internal Medicine covers

A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs. NUCC Health Care Provider Taxonomy, code 207R00000X
Allopathic & Osteopathic Physicians Internal Medicine

All registered taxonomy codes

This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
207R00000X Internal Medicine Physician A065743 CA primary
207RN0300X Nephrology Physician Nephrology A65743 CA

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1558375022 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateJul 28, 2006
Last updatedSep 12, 2025
StatusActive
Sole proprietorNo
CredentialM.D.
Practice address 1414 S GRAND AVE STE 380
Los Angeles, CA 90015
(213) 222-1300
Fax (213) 222-1333
Mailing address 2550 W MAIN ST SUITE 301
Alhambra, CA 91801
This record was updated on Sep 12, 2025, which is recent enough that the contact details are likely still accurate.

Number check

1558375022 passes the NPI check digit test The final digit 2 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 5 5 8 3 7 5 0 2
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 5 1 8 6 7 1 0 4

Sum = 58 · next multiple of 10 = 60 · check digit = 2 · actual last digit = 2

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1558375022?
NPI 1558375022 is the National Provider Identifier assigned to Elsa Hartwick, M.D. in Los Angeles, CA. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Internal Medicine Physician cover?
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive…
How do I contact Elsa Hartwick, M.D.?
The phone number on file with NPPES is (213) 222-1300, last updated Sep 12, 2025. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does Elsa Hartwick, M.D. accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Is NPI 1558375022 a valid number?
Yes. 1558375022 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.