Quick answers
- Which hospitals does Bartholomew D. Sak work at?
- Medicare's official clinician data lists Bartholomew D. Sak at 3 hospitals: Maui Memorial Medical Center, Mercy Health Lakeshore Campus and Trinity Health Muskegon Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Bartholomew D. Sak see patients?
- Medicare's clinician data lists 5 practice locations, including Muskegon, MI, Fremont, MI and Kentwood, MI. Call before your visit to confirm the address.
- What is Bartholomew D. Sak's specialty?
- Medicare lists Internal Medicine as the primary specialty, and also Hospitalist.
- Does Bartholomew D. Sak accept Medicare assignment?
- Yes. Medicare's clinician data says Bartholomew D. Sak accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- What is the phone number for Bartholomew D. Sak?
- (231) 672-3883, as listed in official Medicare / NPI Registry data.
- What is Bartholomew D. Sak's NPI number?
- 1093755167. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Bartholomew D. Sak works
Medicare's Facility Affiliation Data lists Bartholomew D. Sak at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Maui Memorial Medical CenterWailuku, HI · Acute Care Hospital · CCN 120002
- Mercy Health Lakeshore CampusShelby, MI · Critical Access Hospital · CCN 231320
- Trinity Health Muskegon HospitalMuskegon, MI · Acute Care Hospital · CCN 230066
Practice locations
Addresses where Bartholomew D. Sak is enrolled with Medicare (CMS data updated 2026-10-02).
- 1500 E Sherman BlvdMuskegon, MI 49444 (231) 672‑3883
- 212 S Sullivan Ave, Corewell Health Medical Group WestFremont, MI 49412 (616) 391‑3139
- 4444 Kalamazoo Ave SE, 200 Corewell Health Medical Group WestKentwood, MI 49508 (616) 391‑5600
- 5 Atkinson Dr, 302 Corewell Health Medical Group WestLudington, MI 49431 (616) 267‑8700
- 72 S State StShelby, MI 49455 (231) 672‑3883
Group practices
Medicare enrollment lists Bartholomew D. Sak as a member of these groups (CMS data updated 2026-10-02).
- Spectrum Health Primary Care Partners2,294 clinicians in the group
- Mercy Specialty Services90 clinicians in the group
Specialties
- Internal Medicineprimary
- Hospitalistalso
Other internal medicine doctors in Muskegon
Clinicians with the same Medicare primary specialty in Muskegon, MI — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1993 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1093755167 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians