Quick answers
- Which hospitals does Nancy Gryniewicz-Sika work at?
- Medicare's official clinician data lists Nancy Gryniewicz-Sika at 5 hospitals: Loyola Gottlieb Memorial Hospital, Loyola University Medical Center, MacNeal Hospital, Northwestern Medicine Central Dupage Hospital and West Suburban Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Nancy Gryniewicz-Sika see patients?
- Medicare's clinician data lists 2 practice locations, including Oak Park, IL. Call before your visit to confirm the address.
- What is Nancy Gryniewicz-Sika's specialty?
- Medicare lists Family Practice as the primary specialty.
- Does Nancy Gryniewicz-Sika accept Medicare assignment?
- Yes. Medicare's clinician data says Nancy Gryniewicz-Sika 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 Nancy Gryniewicz-Sika?
- (708) 383-0400, as listed in official Medicare / NPI Registry data.
- What is Nancy Gryniewicz-Sika's NPI number?
- 1558368043. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Nancy Gryniewicz-Sika works
Medicare's Facility Affiliation Data lists Nancy Gryniewicz-Sika at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Loyola Gottlieb Memorial HospitalMelrose Park, IL · Acute Care Hospital · CCN 140008
- Loyola University Medical CenterMaywood, IL · Acute Care Hospital · CCN 140276
- MacNeal HospitalBerwyn, IL · Acute Care Hospital · CCN 140054
- Northwestern Medicine Central Dupage HospitalWinfield, IL · Acute Care Hospital · CCN 140242
- West Suburban Medical CenterOak Park, IL · Acute Care Hospital · CCN 140049
Practice locations
Addresses where Nancy Gryniewicz-Sika is enrolled with Medicare (CMS data updated 2026-10-02).
- 1049 Lake St, Suite 201Oak Park, IL 60301
- 965 Lake StOak Park, IL 60301 (708) 383‑0400
Group practices
Medicare enrollment lists Nancy Gryniewicz-Sika as a member of these groups (CMS data updated 2026-10-02).
- Dynamic Physical Therapy, Inc.43 clinicians in the group
- Family Medical Care, Ltd2 clinicians in the group
Specialties
- Family Practiceprimary
Other family doctors in Oak Park
Clinicians with the same Medicare primary specialty in Oak Park, IL — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1994 |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1558368043 |
| 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