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OSCAR ADLER M.D., PHD
NPI 1700874138
Internal Medicine - Nephrology in Leesburg, VA

Active since October 10, 2005PECOS EnrolledAccepts Medicare Assignment
92.61/100
CMS Quality Rating
19490 SANDRIDGE WAY, SUITE 120, LEESBURG, VA 20176(703) 723-5555(703) 562-6996 Get Directions Write a Review

NPPES record last updated: June 2, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Jun 2, 2026, Oct 6, 2023, Aug 3, 2021 and 1 more (4 updates tracked since 2020).

About Oscar Adler M.d., Phd NPPES

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

OSCAR ADLER M.D., PHD (NPI 1700874138) is an individual nephrology provider in Leesburg, Virginia, licensed in Virginia (0101234619) and active in the NPI registry since October 2005. He is enrolled in Medicare PECOS, is affiliated with Inova Loudoun Hospital, and is a graduate of Other (1983).

NPPES Registry Identity

NPI1700874138
Entity TypeIndividualMale
Primary Taxonomy207RN0300X
Provider Legal NameOSCAR ADLERCredential: M.D., PHD
Location Address19490 SANDRIDGE WAY, SUITE 120Leesburg, VA 20176-3469
Mailing Address19490 Sandridge Way Ste 120Lansdowne, VA 20176-3469 · (703) 723-5555 · Fax (703) 858-1251
Phone(703) 723-5555
Fax(703) 562-6996
Sole ProprietorNo
Medical School CMSOtherGraduated 1983
Enumeration DateOctober 10, 2005
Last NPPES UpdateJune 2, 20264 updates tracked since enumeration
NPPES CertifiedJune 2, 2026
✔ NPI 1700874138 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · NephrologyAllopathic & Osteopathic Physicians
Taxonomy Code207RN0300X
License✔ Licensed in VA · 0101234619
Definition
An internist who treats disorders of the kidney, high blood pressure, fluid and mineral balance and dialysis of body wastes when the kidneys do not function. This specialist consults with surgeons about kidney transplantation.
19490 SANDRIDGE WAY, SUITE 120, Leesburg, VA 20176
Open in Google Maps ↗

Other Identifiers 2

Medicaid1700874138VA
Medicaid30015815110001VA

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

Oscar Adler M.d., Phd 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 ID8729029640
PECOS Enrollment IDI20080520000851, I20080520000871
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 Oscar Adler reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Loudoun Medical Group, PC
Same address
Otolaryngology
19490 SANDRIDGE WAY, SUITE 230
Leesburg, VA 20176
  • Reassigned Medicare billing, Virginia and District of Columbia enrollments
  • Also billed through NPI 1043334410 (District of Columbia)
  • 291 clinicians in this Medicare group
NPI 1215051693 (703) 858-5885
Physicians Practice And Research, LLC
0.3 mi
Nephrology
19415 DEERFIELD AVE, SUITE #107
Lansdowne, VA 20176
  • Reassigned Medicare billing, District of Columbia and Virginia enrollments
  • 2 clinicians in this Medicare group
NPI 1851565444 (703) 723-5555

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

Areas of Expertise CMS Part B claims 8

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232
Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.
699 services221 patients
Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
575 services315 patients
Dialysis services, 4 or more physician visits per month (20 years or older) 90960
Dialysis is a treatment that filters and purifies your blood using a machine. It helps keep your fluids and electrolytes in balance when the kidneys can't do their job. This service includes 4 or more visits per month with a physician to monitor your health and adjust your treatment as needed.
202 services25 patients
Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222
Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.
142 services130 patients
New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204
This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.
78 services78 patients
Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223
Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.
40 services39 patients

Hospital Affiliations CMS Care Compare 3

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Inova Loudoun Hospital

Acute Care Hospitals · Leesburg, VA
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number490043
Location44045 Riverside ParkwayLeesburg, VA 20176 · Loudoun County
Emergency services Birthing friendly

Inova Fairfax Hospital

Acute Care Hospitals · Falls Church, VA
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number490063
Location3300 Gallows RoadFalls Church, VA 22042 · Fairfax County
Emergency services Birthing friendly

Reston Hospital Center

Acute Care Hospitals · Reston, VA
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number490107
Location1850 Town Center ParkwayReston, VA 20190 · Fairfax County
Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 20176 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
$129.04 typical visit price
range $56.19 – $170.30
Typical copayment $32.26 (range $14.04 – $42.57)
Most-billed visit code 99204
Established Patient
$99.13 typical visit price
range $18.07 – $138.91
Typical copayment $24.78 (range $4.51 – $34.72)
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.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

92.61/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored through an Alternative Payment Model
Quality85.22
Promoting Interoperability100
Improvement Activities40

Referred Medical Equipment & Supplies CMS DME claims 4

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Cyclosporine, oral, 25 mg J7515
Treatment-Treatment - Miscellaneous · category RX029N
1 supplier13 claims1,560 services$0.60 avg. paid by Medicare
Mycophenolate mofetil, oral, 250 mg J7517
Treatment-Treatment - Miscellaneous · category RX029N
1 supplier11 claims1,320 services$0.20 avg. paid by Medicare
Pharmacy supply fee for oral anti-cancer, oral anti-emetic or immunosuppressive drug(s); for the first prescription in a 30-day period Q0511
Treatment-Chemotherapy · category RH012N
4 suppliers21 claims21 services$18.96 avg. paid by Medicare
Pharmacy supply fee for oral anti-cancer, oral anti-emetic or immunosuppressive drug(s); for a subsequent prescription in a 30-day period Q0512
Treatment-Chemotherapy · category RH012N
2 suppliers21 claims22 services$12.61 avg. paid by Medicare
Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

LOUDOUN MEDICAL GROUP, PC
Internal Medicine (Hypertension Specialist)
19490 SANDRIDGE WAY, SUITE 120
LEESBURG, VA 20176
Loudoun County (703) 723-5555

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 Oscar Adler's NPI number?

The NPI number for Oscar Adler is 1700874138. It was assigned to this individual provider in the NPPES registry on October 10, 2005.

Where is Oscar Adler located?

Oscar Adler practices at 19490 Sandridge Way, Suite 120, Leesburg, VA 20176. The listed phone number is (703) 723-5555.

What is Oscar Adler's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Nephrology, with taxonomy code 207RN0300X.

Is Oscar Adler enrolled in Medicare?

Yes. Oscar Adler 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 organizations bill Medicare for Oscar Adler's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Oscar Adler reassigns Medicare benefits to 2 organizations: Loudoun Medical Group, PC (Leesburg, VA) and Physicians Practice And Research, LLC (Lansdowne, VA). 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 Oscar Adler's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is Oscar Adler affiliated with any hospitals?

According to CMS data, Oscar Adler is affiliated with Inova Loudoun Hospital, Inova Fairfax Hospital and Reston Hospital Center.

When was this NPI record last updated?

The NPPES record for Oscar Adler was last updated on June 2, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.