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Rheumatology

Johnson Ong, DO

Works at hospitals in Loma Linda, CA · California

Summary

Johnson Ong, DO (Rheumatology) is listed by Medicare at 1 hospital in Loma Linda, CA. NPI 1568045508. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Johnson Ong, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

RheumatologyPrimary specialty
YesAccepts Medicare assignment
5Years since medical school (graduated 2021)
MaleGender (as listed)
Faculty Physicians and Surgeons of LlusmGroup practice (+2 more)

Quick answers

Which hospitals does Johnson Ong work at?
Medicare's official clinician data lists Johnson Ong at 1 hospital: Loma Linda University Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Johnson Ong see patients?
Medicare's clinician data lists 7 practice locations, including Loma Linda, CA, San Bernardino, CA and Moreno Valley, CA. Call before your visit to confirm the address.
What is Johnson Ong's specialty?
Medicare lists Rheumatology as the primary specialty, and also Internal Medicine.
Does Johnson Ong accept Medicare assignment?
Yes. Medicare's clinician data says Johnson Ong 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 Johnson Ong?
(909) 382-7100, as listed in official Medicare / NPI Registry data.
What is Johnson Ong's NPI number?
1568045508. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Johnson Ong works

Medicare's Facility Affiliation Data lists Johnson Ong at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Johnson Ong is enrolled with Medicare (CMS data updated 2026-10-02). The first 5 of 7; the Medicare profile lists all.

Group practices

Medicare enrollment lists Johnson Ong as a member of these groups (CMS data updated 2026-10-02).

  • Faculty Physicians and Surgeons of Llusm1,315 clinicians in the group
  • Sac Health System227 clinicians in the group
  • County of Riverside193 clinicians in the group

Specialties

Find other Rheumatology doctors in California →

Other rheumatologists in Loma Linda

Clinicians with the same Medicare primary specialty in Loma Linda, CA — not a recommendation.

All rheumatologists in Loma Linda →

Clinician information

CredentialDO
Graduation year2021
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1568045508
CorrectionsReport 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

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians