Ellen M. Grimm, MD
NPI 1275500100ActiveIndividual· Internal Medicine, Nephrology· San Marcos, TX
Internal Medicine, Nephrology (MD) in San Marcos, Texas, trained at University of Texas Medical School at Houston (class of 1992). Their prescriptions cost Medicare Part D more than their services did: $541,710 for 2,452 claims, against $139,115 paid for services in 2024. Fresenius USA Marketing, Inc. was the largest of 2 companies reporting payments in 2025, $125.41 in all, mostly food and beverage.
Overview
| NPI | 1275500100 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Feb 28, 2006 |
| Last updated in NPPES | Feb 1, 2022 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Nephrology Primary | 207RN0300X | J4170 | TX |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Nov 10, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 11, 2026 | No match | — |
| New York OMIG · Nov 11, 2026 | No match | — |
| Ohio Medicaid · Nov 11, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 11, 2026 | No match | — |
| Washington HCA · Nov 11, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Nephrology (TX) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 212 |
|---|---|
| Services billed | 1,854 across 37 procedure codes |
| Paid by Medicare | $139,115 |
Part D prescriptions in 2024
| Prescriptions (claims) | 2,452 · 5,230 30-day fills |
|---|---|
| Patients | 215 |
| Total drug cost | $541,710 |
| Generic share | 82% of claims |
Education and affiliations
| Medical school | University of Texas Medical School at Houston |
|---|---|
| Graduation year | 1992 |
| Medicare specialty | Nephrology |
| Telehealth | Offers telehealth |
Medical group
- The Austin Diagnostic Clinic PLLCCedar Park, TX · 86 clinicians
Hospital affiliations
- Ascension Seton HaysKyle, TX
- Christus Santa Rosa Hospital-San MarcosSan Marcos, TX
- St David's Medical CenterAustin, TX
- St David's South Austin Medical CenterAustin, TX
Other facilities
- Fresenius Medical Care KyleDialysis facility · Kyle, TX
- Nna San MarcosDialysis facility · San Marcos, TX
- Christus HomecareHome health agency · New Braunfels, TX
Industry payments (Open Payments)
- 2025$125.41 · 3 payments from 2 companies
- 2024$281.81 · 7 payments from 4 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Fresenius USA Marketing, Inc. | $107.98 | 2 |
| Ani Pharmaceuticals, Inc. | $17.43 | 1 |
What the 2025 payments were for
- Food and Beverage$125.41 · 3 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
Other nephrologists in San Marcos
- 1316137722