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GRETEL DAYNA D'SOUZA M.D.
NPI 1679138531
Internal Medicine - Rheumatology in Sylmar, CA

Active since May 07, 2019PECOS EnrolledAccepts Medicare Assignment
14445 OLIVE VIEW DR, SYLMAR, CA 91342(747) 210-3205(805) 569-8358 Get Directions Write a Review

NPPES record last updated: July 27, 2022. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Jul 27, 2022, May 7, 2019 (2 updates tracked since 2019).

About Gretel Dayna D'souza M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

GRETEL DAYNA D'SOUZA M.D. (NPI 1679138531) is an individual rheumatology provider in Sylmar, California, licensed in California (178675) and active in the NPI registry since May 2019. She is enrolled in Medicare PECOS, maintains a secondary practice location in Santa Barbara, and is a graduate of Other (2018).

NPPES Registry Identity

NPI1679138531
Entity TypeIndividualFemale
Primary Taxonomy207RR0500X
Provider Legal NameGRETEL DAYNA D'SOUZACredential: M.D.
Location Address14445 OLIVE VIEW DRSylmar, CA 91342-1437
Mailing Address14445 Olive View DrSylmar, CA 91342-1437 · (747) 210-3205 · Fax (805) 569-8358
Phone(747) 210-3205
Fax(805) 569-8358
Sole ProprietorNo
Medical School CMSOtherGraduated 2018
Enumeration DateMay 7, 2019
Last NPPES UpdateJuly 27, 20222 updates tracked since enumeration
NPPES CertifiedJuly 27, 2022
✔ NPI 1679138531 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · RheumatologyAllopathic & Osteopathic Physicians
Taxonomy Code207RR0500X
License✔ Licensed in CA · 178675
Definition
An internist who treats diseases of joints, muscle, bones and tendons. This specialist diagnoses and treats arthritis, back pain, muscle strains, common athletic injuries and collagen diseases.
Also ListedStudent in an Organized Health Care Education/Training ProgramTaxonomy 390200000X
14445 OLIVE VIEW DR, Sylmar, CA 91342
Open in Google Maps ↗

Secondary Practice Location 1

Location 1SBCH, Medical Education, 400 W Pueblo StreetSanta Barbara, CA 93015 · Phone (805) 569-7315 · Fax (805) 569-8358

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

Gretel Dayna D'souza M.d. 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.

PECOS PAC ID8820537533
PECOS Enrollment IDI20240826004035
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Gretel D'souza reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Lakeside Medical Organization, A Medical Group Inc.
12 mi
Internal Medicine
8501 FALLBROOK AVE STE 300
West Hills, CA 91304
  • Reassigned Medicare billing, California enrollment
  • 205 clinicians in this Medicare group
NPI 1831426642 (818) 654-3400

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 91342 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$142.39 typical visit price
range $62.96 – $187.60
Typical copayment $35.59 (range $15.74 – $46.90)
Most-billed visit code 99204
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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.

COUNTY OF LOS ANGELES AUDITOR CONTROLLER
General Acute Care Hospital
14445 OLIVE VIEW DR
SYLMAR, CA 91342
Los Angeles County (818) 364-1555
DENNIS POON
Nurse Practitioner (Family)
14445 OLIVE VIEW DR
SYLMAR, CA 91342
Los Angeles County (747) 210-3000
SERENA KE MD
Student in an Organized Health Care Education/Training Program
14445 OLIVE VIEW DR
SYLMAR, CA 91342
Los Angeles County (747) 210-3205
DR. PAUL I LIU M.D.
Pathology (Anatomic Pathology & Clinical Pathology)
14445 OLIVE VIEW DR, ROOM 1A116
SYLMAR, CA 91342
Los Angeles County (818) 364-4033
DR. ARTHUR JENG M.D.
Internal Medicine (Infectious Disease)
14445 OLIVE VIEW DR, 2B182
SYLMAR, CA 91342
Los Angeles County (818) 364-3205
MRS. CECILIA CORONADO PTA
Physical Therapy Assistant
14445 OLIVE VIEW DR
SYLMAR, CA 91342
Los Angeles County (747) 210-4245
COUNTY OF LOS ANGELES AUDITOR CONTROLLER
General Acute Care Hospital
14445 OLIVE VIEW DR
SYLMAR, CA 91342
Los Angeles County (818) 364-1555
MR. ANDRIY A KUZNETSOV PT
Physical Therapist
14445 OLIVE VIEW DR
SYLMAR, CA 91342
Los Angeles County (818) 364-4245

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 Gretel D'souza's NPI number?

The NPI number for Gretel D'souza is 1679138531. It was assigned to this individual provider in the NPPES registry on May 7, 2019.

Where is Gretel D'souza located?

Gretel D'souza practices at 14445 Olive View Dr, Sylmar, CA 91342. The listed phone number is (747) 210-3205.

What is Gretel D'souza's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Rheumatology, with taxonomy code 207RR0500X.

Is Gretel D'souza enrolled in Medicare?

Yes. Gretel D'souza 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 organization bills Medicare for Gretel D'souza's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gretel D'souza reassigns Medicare benefits to Lakeside Medical Organization, A Medical Group Inc. (West Hills, CA). The 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 Gretel D'souza's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Gretel D'souza was last updated on July 27, 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.