Individual provider

Rachel Mittelstaedt, MD

Internal Medicine Physician Hospitalist Physician Infectious Disease Physician Medicare enrolled

Rachel Mittelstaedt, MD is an Infectious Disease Physician in Boston, MA, registered under NPI 1518323815. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty.

Getting there

The practice address on file is 55 FRUIT ST, Boston, MA 02114. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

55 FRUIT ST, Boston, MA 02114 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
D0091130 MD Internal Medicine Physician
D91130 MD Hospitalist Physician
293846 MA Infectious Disease Physician primary

Licences are recorded in 2 states: MD, MA. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Infectious Disease
PAC ID
2365793080
Enrollment ID
I20240424001417

Medicare enrolment is recorded as approved under the provider type Practitioner - Infectious Disease. 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.

Licensed in 2 states

This provider holds licences in 2 states: Massachusetts and Maryland. The practice address on file is in Boston, MA, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.

MA Massachusetts practice address
Licence
293846
Specialty
Infectious Disease Physician
Verify with the MA board →
MD Maryland
Licence
D0091130
Specialty
Internal Medicine Physician
Verify with the MD board →

Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.

What Infectious Disease covers

An internist who deals with infectious diseases of all types and in all organ systems. Conditions requiring selective use of antibiotics call for this special skill. This physician often diagnoses and treats AIDS patients and patients with fevers which have not been explained. Infectious disease specialists may also have expertise in preventive medicine and travel medicine. NUCC Health Care Provider Taxonomy, code 207RI0200X
Allopathic & Osteopathic Physicians Internal Medicine Infectious Disease

All registered taxonomy codes

This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
207R00000X Internal Medicine Physician D0091130 MD
208M00000X Hospitalist Physician D91130 MD
207RI0200X Infectious Disease Physician Infectious Disease 293846 MA primary

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.

NPI1518323815 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateJan 4, 2016
Last updatedSep 1, 2023
StatusActive
Sole proprietorNo
GenderFemale
CredentialMD
Practice address 55 FRUIT ST
Boston, MA 02114
(617) 726-2000
Mailing address 6201 GREENLEIGH AVE
Baltimore, MD 21220
The last update on file is Sep 1, 2023. Providers are only required to update NPPES when their information changes, so an older date does not necessarily mean the details are wrong — but it is worth a quick call before you travel.

Number check

1518323815 passes the NPI check digit test The final digit 5 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 1 8 3 2 3 8 1
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 5 2 8 6 2 6 8 2

Sum = 65 · next multiple of 10 = 70 · check digit = 5 · actual last digit = 5

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 1518323815?
NPI 1518323815 is the National Provider Identifier assigned to Rachel Mittelstaedt, MD in Boston, MA. 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 Infectious Disease cover?
An internist who deals with infectious diseases of all types and in all organ systems. Conditions requiring selective use of antibiotics call for this special skill. This physician often diagnoses and treats AIDS patients and patients with fevers which have not been explained. Infectious disease specialists may also…
How do I contact Rachel Mittelstaedt, MD?
The phone number on file with NPPES is (617) 726-2000, last updated Sep 1, 2023. 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 Rachel Mittelstaedt, MD 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 1518323815 a valid number?
Yes. 1518323815 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.