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ENDOCRINE ASSOCIATES, LLC
NPI 1134670367
Internal Medicine - Endocrinology, Diabetes & Metabolism in Chesterfield, MO

Active since October 24, 2016CLIA Certified · 2 labs
224 S WOODS MILL RD STE 480S, CHESTERFIELD, MO 63017(636) 685-7744(314) 590-5957 Get Directions Write a Review

NPPES record last updated: March 5, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Mar 5, 2026, Dec 12, 2025, Apr 26, 2021 and 2 more (5 updates tracked since 2016).

About Endocrine Associates, Llc NPPES

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

ENDOCRINE ASSOCIATES, LLC (NPI 1134670367) is a healthcare organization registered as an endocrinology, diabetes & metabolism in Chesterfield, Missouri and active in the NPI registry since October 2016. The organization holds 2 active CLIA laboratory certificates, maintains a secondary practice location in Saint Louis, and lists Darren R. Haskell, Chief Medical Officer, as its authorized official.

NPPES Registry Identity

NPI1134670367
Entity TypeOrganization
Primary Taxonomy207RE0101X
Legal Business NameENDOCRINE ASSOCIATES, LLC
Location Address224 S WOODS MILL RD STE 480SChesterfield, MO 63017-3609
Mailing Address224 S Woods Mill Rd Ste 480sChesterfield, MO 63017-3609 · (636) 685-7744 · Fax (314) 590-5957
Phone(636) 685-7744
Fax(314) 590-5957
Organization SubpartYesParent: St. Lukes Medical Group
Authorized OfficialDarren R. HaskellChief Medical Officer · (314) 205-6444
Enumeration DateOctober 24, 2016
Last NPPES UpdateMarch 5, 20265 updates tracked since enumeration
NPPES CertifiedMarch 5, 2026
✔ NPI 1134670367 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Endocrinology, Diabetes & MetabolismAllopathic & Osteopathic Physicians
Taxonomy Code207RE0101X
Definition
An internist who concentrates on disorders of the internal (endocrine) glands such as the thyroid and adrenal glands. This specialist also deals with disorders such as diabetes, metabolic and nutritional disorders, obesity, pituitary diseases and menstrual and sexual problems.
224 S WOODS MILL RD STE 480S, Chesterfield, MO 63017
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Secondary Practice Location 1

Location 12315 Dougherty Ferry Rd Ste 109BSaint Louis, MO 63122-3383 · Phone (314) 965-9133 · Fax (314) 984-2793

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Arkansas Health & Wellness, Ambetter from Sunflower Health Plan, Ambetter Health and more.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Endocrine Associates, Llc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

5

Medicare enrollment records show 5 clinicians reassign Medicare billing to Endocrine Associates, LLC, which bills Medicare for the services they deliver. Of these, 5 practice within 10 miles. They are listed nearest first.

Clinicians, nearest first (5)

Vaishaliben Ahir, MD
Internal Medicine
NPI 1376706861
224 S WOODS MILL RD STE 480S
Chesterfield, MO 63017
(636) 685-7744
✔ PECOS✔ Accepts Medicare0.7 mi
Karen Chang-Chen, MD
Endocrinology
NPI 1508916495
224 S WOODS MILL RD STE 480S
Chesterfield, MO 63017
(636) 685-7744
✔ PECOS✔ Accepts Medicare0.7 mi
Soumya Nadella, M.D.
Endocrinology
NPI 1316350028
224 S WOODS MILL RD STE 480S
Chesterfield, MO 63017
(366) 857-7446
✔ PECOS✔ Accepts Medicare0.7 mi
Hassan Ahmad, M.D
Allergy/Immunology
NPI 1194138024
226 S WOODS MILL RD STE 47W
Chesterfield, MO 63017
(314) 205-6600
✔ PECOS✔ Accepts Medicare0.7 mi
Mireille El Hayek, M.D.
Endocrinology
NPI 1912139940
2315 DOUGHERTY FERRY ROAD SUITE 109B
Saint Louis, MO 63122
(314) 965-9133
✔ PECOS✔ Accepts Medicare5.5 mi

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

CLIA Laboratory Certificates CMS CLIA 2

Laboratory certificates issued under the Clinical Laboratory Improvement Amendments (CLIA) program, which sets federal quality standards for human laboratory testing in the United States. There is no official CMS crosswalk between CLIA and NPI numbers; these certificates are associated with this NPI by matching facility names, locations and phone numbers in the CMS CLIA registry.

Certificate of Waiver 26D2169093

Endocrine Associates, LLC · Saint Louis, MO
Active · expires Jul 15, 2027
CLIA Number26D2169093
Laboratory TypePhysician Office
Certificate Effective DateJuly 16, 2025
Certificate Expiration DateJuly 15, 2027
Laboratory DirectorHoly Dachroeden
Laboratory Phone(314) 965-9133
Laboratory LocationEndocrine Associates, LLC2315 Dougherty Ferry Rd, Suite 109B, Saint Louis, MO 63122
CLIA data matches this NPI record on: Address Name Phone
This certificate is issued to a laboratory to perform only waived tests.

Certificate of Waiver 26D2121797

Endocrine Associates, LLC · Chesterfield, MO
Active · expires Nov 14, 2026
CLIA Number26D2121797
Laboratory TypePhysician Office
Certificate Effective DateNovember 15, 2024
Certificate Expiration DateNovember 14, 2026
Laboratory DirectorKaren J. Chang-Chen
Laboratory Phone(636) 685-7744
Laboratory LocationEndocrine Associates, LLC226 S Woods Mill Rd Ste 40 West, Chesterfield, MO 63017
CLIA data matches this NPI record on: Name Phone
This certificate is issued to a laboratory to perform only waived tests.

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 Endocrine Associates, LLC's NPI number?

The NPI number for Endocrine Associates, LLC is 1134670367. It was assigned to this organization in the NPPES registry on October 24, 2016.

Where is Endocrine Associates, LLC located?

Endocrine Associates, LLC is located at 224 S Woods Mill Rd Ste 480S, Chesterfield, MO 63017. The listed phone number is (636) 685-7744.

What is Endocrine Associates, LLC's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Endocrinology, Diabetes & Metabolism, with taxonomy code 207RE0101X.

Is Endocrine Associates, LLC enrolled in Medicare?

Yes. Endocrine Associates, LLC is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Endocrine Associates, LLC?

According to the CMS Revalidation Reassignment List (October 2026 release), 5 clinicians in 3 Medicare specialties reassign their Medicare billing to Endocrine Associates, LLC. A 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 the clinician's services. The largest specialties are Endocrinology (3), Allergy/Immunology (1) and Internal Medicine (1). Of these, 5 practice within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Does Endocrine Associates, LLC hold CLIA laboratory certificates?

Yes. 2 active CLIA laboratory certificates are associated with this NPI under the federal Clinical Laboratory Improvement Amendments program. The certificates are listed in the CLIA Laboratory Certificates section above.

What insurance does Endocrine Associates, LLC accept?

Health plans from Ambetter Health, Ambetter Health of Delaware, Ambetter from Arkansas Health & Wellness, Ambetter from Sunflower Health Plan and Ambetter of Oklahoma and 3 other insurers list Endocrine Associates, LLC as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Endocrine Associates, LLC was last updated on March 5, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 months 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.