LOUDOUN MEDICAL GROUP, PC
NPI 1164546529
Internal Medicine - Infectious Disease in Leesburg, VA

Q: What is Loudoun Medical Group, PC's NPI number?

The NPI number for Loudoun Medical Group, PC is 1164546529. It was assigned to this organization in the NPPES registry on March 19, 2007. The provider is doing business as Infectious Diseases, Tropical Medicine & Travel Clinic.

Q: What is Loudoun Medical Group, PC's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Infectious Disease, with taxonomy code 207RI0200X.

Active since March 19, 2007

44035 RIVERSIDE PARKWAY, SUITE 440, LEESBURG, VA 20176(703) 858-9966(703) 858-9177 Get Directions Write a Review

NPPES record last updated: November 20, 2025. Verified against the NPPES registry weekly; last sync: November 08, 2026.

Record update history: Nov 20, 2025, Sep 20, 2022, Mar 12, 2022 and 1 more (4 updates tracked since 2021).

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About Loudoun Medical Group, Pc NPPES

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

LOUDOUN MEDICAL GROUP, PC (NPI 1164546529), doing business as Infectious Diseases, Tropical Medicine & Travel Clinic, is a healthcare organization registered as an infectious disease in Leesburg, Virginia and active in the NPI registry since March 2007. The organization maintains a secondary practice location in Alexandria and lists Mary Beth Tamasy, Ceo, as its authorized official.

NPPES Registry Identity

NPI1164546529

Entity TypeOrganization

Primary Taxonomy207RI0200X

Legal Business NameLOUDOUN MEDICAL GROUP, PC

Location Address44035 RIVERSIDE PARKWAY, SUITE 440Leesburg, VA 20176-8260

Mailing Address224d Cornwall St Nw Ste 403Leesburg, VA 20176-2704 · (703) 737-6001 · Fax (571) 291-9786

Phone(703) 858-9966

Fax(703) 858-9177

Organization SubpartYes

Authorized OfficialMary Beth TamasyCeo · (703) 737-6010

Enumeration DateMarch 19, 2007

Last NPPES UpdateNovember 20, 20254 updates tracked since enumeration

NPPES CertifiedNovember 20, 2025

✔ NPI 1164546529 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Infectious DiseaseAllopathic & Osteopathic Physicians

Taxonomy Code207RI0200X

Definition

An internist who deals with infectious diseases of all types and in all organ systems. Conditions requiring selective use of antibiotics call for this special skill. This physician often diagnoses and treats AIDS patients and patients with fevers which have not been explained. Infectious disease specialists may also have expertise in preventive medicine and travel medicine.

44035 RIVERSIDE PARKWAY, SUITE 440, Leesburg, VA 20176

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Other Names 1

Doing Business AsInfectious Diseases, Tropical Medicine & Travel Clinic

Secondary Practice Location 1

Location 14320 Seminary RdAlexandria, VA 22304-1535 · Phone (703) 504-3000

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

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Loudoun Medical Group, Pc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

291

Medicare enrollment records show 291 clinicians reassign Medicare billing to Loudoun Medical Group, PC, which bills Medicare for the services they deliver. Of these, 1 practice at this address and 194 within 10 miles. Listed here are the 20 practicing nearest to this location.

Clinicians by Medicare Specialty 35

Nurse Practitioner82

Family Practice29

Diagnostic Radiology24

Internal Medicine22

Certified Nurse Midwife (CNM)16

Obstetrics/Gynecology13

Urology13

Gastroenterology9

27 other specialties83

Nearest to this location (20)

See all 291

Sarfraz Choudhary, MD

Infectious Disease

NPI 1619960242

44035 RIVERSIDE PARKWAY, SUITE 440
Leesburg, VA 20176

(703) 858-9966

✔ PECOS✔ Accepts MedicareSame address

Jennifer Francisco, FNP BC

Nurse Practitioner

NPI 1861944837

44045 RIVERSIDE PKWY
Leesburg, VA 20176

(703) 858-8074

✔ PECOS✔ Accepts Medicare0.1 mi

Gavin Foster, MD

Obstetrics/Gynecology

NPI 1609860915

44055 RIVERSIDE PKWY STE 238
Leesburg, VA 20176

(703) 858-3070

✔ PECOS0.1 mi

Shannon Lehr, M.D.

General Surgery

NPI 1497847347

44055 RIVERSIDE PKWY SUITE 246
Leesburg, VA 20176

(703) 858-3200

✔ PECOS0.1 mi

Jon Mader, M.D.

Physical Medicine and Rehabilitation

NPI 1255656864

44055 RIVERSIDE PARKWAY, SUITE 216
Leesburg, VA 20176

(703) 840-0665

✔ PECOS✔ Accepts Medicare0.1 mi

Shahid Siddiqui

Internal Medicine

NPI 1386662757

44055 RIVERSIDE PARKWAY, SUITE 216
Leesburg, VA 20176

(703) 858-1395

✔ PECOS✔ Accepts Medicare0.1 mi

David Boyd, M.D., M.B.A.

Diagnostic Radiology

NPI 1265688048

19500 SANDRIDGE WAY, SUITE 420
Leesburg, VA 20176

(571) 375-8601

✔ PECOS✔ Accepts Medicare0.1 mi

Mei-Hwa Firestone, MD

Hematology/Oncology

NPI 1699909093

19500 SANDRIDGE WAY, SUITE 450
Leesburg, VA 20176

(703) 656-9805

✔ PECOS✔ Accepts Medicare0.1 mi

Lindsay Roach, D.O.

Pediatric Medicine

NPI 1659695526

19500 SANDRIDGE WAY SUITE 110
Leesburg, VA 20176

(703) 723-7337

✔ PECOS0.1 mi

Michael Grimm, MD

Interventional Radiology

NPI 1447238050

19500 SANDRIDGE WAY, SUITE 420
Leesburg, VA 20176

(571) 375-8601

✔ PECOS✔ Accepts Medicare0.1 mi

Kessie Herring, CNM

Certified Nurse Midwife (CNM)

NPI 1376305045

19455 DEERFIELD AVENUE, SUITE 204
Leesburg, VA 20176

(703) 858-1500

✔ PECOS✔ Accepts Medicare0.2 mi

Michael Todd, MD

Dermatology

NPI 1609860337

19465 DEERFIELD AVE SUITE 401
Leesburg, VA 20176

(703) 723-5700

✔ PECOS✔ Accepts Medicare0.2 mi

Lakshmi Mahendran

Physical Therapist in Private Practice

NPI 1841807278

19465 DEERFIELD AVENUE, SUITE 208
Leesburg, VA 20176

(571) 580-0220

✔ Accepts Medicare0.2 mi

Nauman Akhtar, M.D.

Orthopedic Surgery

NPI 1003017682

19450 DEERFIELD AVENUE, SUITE 200
Leesburg, VA 20176

(571) 209-1875

✔ PECOS✔ Accepts Medicare0.2 mi

Christopher Bourke, D.P.M.

Podiatry

NPI 1225456361

19450 DEERFIELD AVE STE 200
Leesburg, VA 20176

(703) 777-3262

✔ PECOS✔ Accepts Medicare0.2 mi

Yaser Cheema, MD

Interventional Cardiology

NPI 1124209663

19450 DEERFIELD AVENUE, SUITE 325
Leesburg, VA 20176

(703) 202-1111

✔ PECOS✔ Accepts Medicare0.2 mi

Catherine Ellis, M.D.

Endocrinology

NPI 1548473150

19450 DEERFIELD AVENUE, SUITE 200
Leesburg, VA 20176

(703) 844-8380

✔ PECOS✔ Accepts Medicare0.2 mi

Nadeem Khan, MD

Gastroenterology

NPI 1396708392

19450 DEERFIELD AVENUE, SUITE 335
Leesburg, VA 20176

(703) 858-3060

✔ PECOS✔ Accepts Medicare0.2 mi

Oscar Adler, M.D., PHD

Nephrology

NPI 1700874138

19490 SANDRIDGE WAY, SUITE 120
Leesburg, VA 20176

(703) 723-5555

✔ PECOS✔ Accepts Medicare0.2 mi

Kimberly Johnson, AU.D., CCC-A

Qualified Audiologist

NPI 1063630234

19490 SANDRIDGE WAY, SUITE 230
Leesburg, VA 20176

(703) 858-5885

✔ Accepts Medicare0.2 mi

See all 291 clinicians

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 Loudoun Medical Group, PC's NPI number?

The NPI number for Loudoun Medical Group, PC is 1164546529. It was assigned to this organization in the NPPES registry on March 19, 2007. The provider is doing business as Infectious Diseases, Tropical Medicine & Travel Clinic.

Where is Loudoun Medical Group, PC located?

Loudoun Medical Group, PC is located at 44035 Riverside Parkway, Suite 440, Leesburg, VA 20176. The listed phone number is (703) 858-9966.

What is Loudoun Medical Group, PC's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Infectious Disease, with taxonomy code 207RI0200X.

Is Loudoun Medical Group, PC enrolled in Medicare?

Yes. Loudoun Medical Group, PC is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Loudoun Medical Group, PC?

According to the CMS Revalidation Reassignment List (October 2026 release), 291 clinicians in 35 Medicare specialties reassign their Medicare billing to Loudoun Medical Group, PC. 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 Nurse Practitioner (82), Family Practice (29) and Diagnostic Radiology (24). Of these, 1 practice at this address and 194 within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Loudoun Medical Group, PC was last updated on November 20, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 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.