SIOBHAN M CASE MD, MHS
NPI 1770901639
Internal Medicine - Rheumatology in Boston, MA
About Siobhan M Case Md, Mhs NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
SIOBHAN M CASE MD, MHS (NPI 1770901639) is an individual rheumatology provider in Boston, Massachusetts, licensed in Massachusetts (271300) and active in the NPI registry since March 2014. She is enrolled in Medicare PECOS, is affiliated with Brigham And Women's Hospital, and maintains a secondary practice location in Boston.
NPPES Registry Identity
Specialties & Licenses 3
Secondary Practice Location 1
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
Siobhan M Case Md, Mhs is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Billing Reassignments
2Medicare enrollment records show Siobhan Case reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Boston, MA 02115
- Reassigned Medicare billing, Massachusetts enrollment
- 4,574 clinicians in this Medicare group
Boston, MA 02115
- Reassigned Medicare billing, Massachusetts enrollment
- 1,358 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Areas of Expertise CMS Part B claims
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Brigham And Women's Hospital
Acute Care Hospitals · Boston, MAPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 02115 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Other Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
BOSTON, MA 02115
BOSTON, MA 02115
BOSTON, MA 02115
BOSTON, MA 02115
Frequently Asked Questions NPPES & CMS
Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.
What is Siobhan Case's NPI number?
The NPI number for Siobhan Case is 1770901639. It was assigned to this individual provider in the NPPES registry on March 28, 2014.
Where is Siobhan Case located?
Siobhan Case practices at 75 Francis St, Boston, MA 02115. The listed phone number is (617) 732-5500.
What is Siobhan Case's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Rheumatology, with taxonomy code 207RR0500X.
Is Siobhan Case enrolled in Medicare?
Yes. Siobhan Case is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.
Which organizations bill Medicare for Siobhan Case's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Siobhan Case reassigns Medicare benefits to 2 organizations: Brigham & Womens Physicians Organization Inc (Boston, MA) and Children's Hospital Pediatric Associates, Inc (Boston, MA). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Siobhan Case's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Siobhan Case accept?
Health plans from Taro Health list Siobhan Case as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.
Is Siobhan Case affiliated with any hospitals?
According to CMS data, Siobhan Case is affiliated with Brigham And Women's Hospital.
When was this NPI record last updated?
The NPPES record for Siobhan Case was last updated on May 25, 2022. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.
# Siobhan M Case, MD, MHS · NPI 1770901639
Rheumatology physician in Boston, Massachusetts. Individual provider, active in the CMS NPPES registry since March 28, 2014.
## Identity
- **NPI:** 1770901639 (Entity type: Individual)
- **Enumerated:** March 28, 2014
- **Primary specialty:** Internal Medicine - Rheumatology · taxonomy 207RR0500X
- **State license:** 271300 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** 75 FRANCIS ST, Boston, MA 02115-6110
- **Phone:** (617) 732-5500
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): Brigham & Womens Physicians Organization Inc (NPI 1033535497, Boston, MA); Children's Hospital Pediatric Associates, Inc (NPI 1457306664, Boston, MA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Yale University School Of Medicine, class of 2014
## Record status
- **NPPES last updated:** May 25, 2022
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Source: [NPI Profile](https://npiprofile.com/npi/1770901639) · Data from the CMS NPPES public registry.