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Emergency Medicine

Kristin M. Lewis, MD

Works at hospitals in Orange, CA · California

Summary

Dr. Kristin M. Lewis, MD is an emergency medicine doctor at 101 The City Dr S, Orange, CA 92868. Phone: (714) 456-7004. Accepts Medicare assignment. In 2024, Kristin M. Lewis had 426 Original Medicare patients and 539 services. NPI 1225590201. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Emergency medicine doctor (Medicare lists Emergency Medicine)
  • Address: 101 The City Dr S, Orange, CA 92868 · Directions
  • Phone: (714) 456‑7004
  • Medicare: Accepts Medicare assignment
  • Hospital: UCI Health-Orange
  • Group practice: Regents of the University of
  • Medical school: University Of California, San Francisco School Of Medicine · graduated 2019 (7 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Kristin M. Lewis, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Kristin M. Lewis accept Medicare assignment?
Yes. Medicare's clinician data says Kristin M. Lewis accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Kristin M. Lewis see?
In 2024, CMS data shows 426 Original Medicare patients and 539 services for Kristin M. Lewis. This counts Original Medicare only and measures volume, not quality.
What is Kristin M. Lewis's NPI number?
1225590201. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Kristin M. Lewis, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients426
Services billed to Medicare539
Different services or procedures32
Participating Medicare providerYes
Average age of these patients75

Most frequent services

  1. Emergency department visit with high level of medical decision making (99285)223 services
  2. Critical care, first 30-74 minutes (99291)120 services
  3. Emergency department visit with moderate level of medical decision making (99284)81 services
  4. Limited ultrasound scan of abdomen (76705)23 services
  5. Ultrasound of heart, follow-up (93308)22 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Chronic kidney disease53%
  • Diabetes52%
  • Arthritis52%
  • Ischemic heart disease44%

Hospitals where Kristin M. Lewis works

Medicare's Facility Affiliation Data lists Kristin M. Lewis at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

  • UCI Health-OrangeOrange, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050348

Practice locations

Addresses where Kristin M. Lewis is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Kristin M. Lewis as a member of this group (CMS data updated October 2, 2026).

  • Regents of the University of129 clinicians in the group

Specialties

Find other Emergency Medicine doctors in California →

Other emergency medicine doctors in Orange

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

All emergency medicine doctors in Orange →

Other clinicians in Regents of the University of

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolUniversity Of California, San Francisco School Of Medicine
Graduation year2019 (7 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1225590201
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 October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians