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DR. DIONISIO A. FERNANDES MD
NPI 1285691121
Allergy & Immunology - Allergy in San Leandro, CA

Active since April 26, 2006PECOS Enrolled
13847 E 14TH ST., STE 112, SAN LEANDRO, CA 94578(510) 352-8585(510) 352-8644 Get Directions Write a Review

NPPES record last updated: October 25, 2018. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Oct 25, 2018, Aug 17, 2016 (2 updates tracked since 2016).

About Dr. Dionisio A. Fernandes Md NPPES

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

DR. DIONISIO A. FERNANDES MD (NPI 1285691121) is an individual allergy provider in San Leandro, California, licensed in California (A29416) and active in the NPI registry since April 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1285691121
Entity TypeIndividualMale
Primary Taxonomy207KA0200X
Provider Legal NameDR. DIONISIO A. FERNANDESCredential: MD
Location Address13847 E 14TH ST., STE 112San Leandro, CA 94578
Mailing Address3448 Mowry AveFremont, CA 94538-1422 · (510) 373-3000 · Fax (510) 744-9959
Phone(510) 352-8585
Fax(510) 352-8644
Sole ProprietorNo
Enumeration DateApril 26, 2006
Last NPPES UpdateOctober 25, 20182 updates tracked since enumeration
✔ NPI 1285691121 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAllergy & Immunology · AllergyAllopathic & Osteopathic Physicians
Taxonomy Code207KA0200X
License✔ Licensed in CA · A29416
Definition
A physician who specializes in the diagnosis, treatment, and management of allergies. Source: National Uniform Claim Committee
13847 E 14TH ST., San Leandro, CA 94578
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Other Identifiers 2

MedicaidGR0066330CA
MedicaidGR0066331CA

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Dionisio A. Fernandes Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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 Reassignments

2

Medicare enrollment records show Dionisio Fernandes reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

The Davis Street Community Center Incorporated
0.9 mi
Federally Qualified Health Center (FQHC)
3081 TEGARDEN
San Leandro, CA 94577
  • Reassigned Medicare billing, California enrollment
  • 42 clinicians in this Medicare group
NPI 1215358924 (510) 347-4620
Baz Allergy, Asthma & Sinus Center, Inc.
3.2 mi
Allergy
20100 LAKE CHABOT RD, STE. 2
Castro Valley, CA 94546
  • Reassigned Medicare billing, California enrollment
  • 41 clinicians in this Medicare group
NPI 1568842417 (510) 969-5418

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

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 Dionisio Fernandes's NPI number?

The NPI number for Dionisio Fernandes is 1285691121. It was assigned to this individual provider in the NPPES registry on April 26, 2006.

Where is Dionisio Fernandes located?

Dionisio Fernandes practices at 13847 E 14th St. Ste 112, San Leandro, CA 94578. The listed phone number is (510) 352-8585.

What is Dionisio Fernandes's specialty?

The primary specialty registered for this NPI is Allergy & Immunology, specializing in Allergy, with taxonomy code 207KA0200X.

Is Dionisio Fernandes enrolled in Medicare?

Yes. Dionisio Fernandes is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Dionisio Fernandes's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Dionisio Fernandes reassigns Medicare benefits to 2 organizations: The Davis Street Community Center Incorporated (San Leandro, CA) and Baz Allergy, Asthma & Sinus Center, Inc. (Castro Valley, CA). Each 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 Dionisio Fernandes'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 Dionisio Fernandes was last updated on October 25, 2018. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 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.