NPI registry status
Active
2026 NPPES data Nephrology Physician NPI 1659439867 MD
Verify on CMS → Michael Portner, MD
Nephrology Physician in Cleveland, Mississippi.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 10,806 in Nephrology Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
Federal data, no proprietary rating.
We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
1K
Medicare Part D claims · 136 beneficiaries · Nephrology Physician avg: 2K
Generic prescribing
80%
generic claims · 20% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2024
What the federal data shows
Michael Portner, MD filed 1,271 Medicare Part D claims in 2024 as a Nephrology Physician in Cleveland, Mississippi, prescribing 80% generic.
- 1K
- Part D claims, 2024
- 80%
- generic prescribing
- Likely
- board-certified (heuristic)
- ≥78th
- pct by Part D claim volume (lower-bound band)
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) - no proprietary rating or editorial opinion is applied.
Federal trust snapshot
What official records show about Michael Portner, MD
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1659439867), first enumerated 12/04/2006.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 1,271 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Heuristic suggests board-certified status based on ABMS-eligible specialty taxonomy plus active CMS participation signals — not a direct ABMS verification.
- Reported
Hospital affiliations
2 CMS Care Compare hospital affiliations on record — practice footprint from the Doctors and Clinicians file.
Source: CMS Care Compare
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1659439867 · Nephrology Physician
NPI-10 · ENUM-LEGACY · TAX-MID · RX-MID · BOOK-THIN · PHOTO-ENUM
- NPI-10 1659439867
- ENUM-LEGACY 2006
- TAX-MID 11K Nephrology Physician
- RX-MID 1,271
- BOOK-THIN 95 in Mississippi
- PHOTO-ENUM Clement Nwosu · 2006
Michael Portner, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
1,271 ≥ 78th percentile 78% of 1,416,883 prescribers are in lower value bands
Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2024
✓
Board certification likely (heuristic, not verified)
Michael Portner, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 2 hospital affiliations - signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Michael Portner, MD?
Quality data not reportedPrimary specialty
Nephrology Physician
Medicare Part D claims
1,271 16% vs specialty avg
Specialty distribution in Mississippi
How Nephrology Physician compares to other specialties among Mississippi providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Nephrology Physician. Verify directly:
How MIPS and board certification work
The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).
Practice Address
Provider Details
| NPI | 1659439867 |
|---|---|
| Specialty | Nephrology Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 12/04/2006 |
Hospital and facility affiliations
Facilities where Michael Portner, MD bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" - a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.
Delta Hills Nephrology Associates
Greenwood, MS
Delta Hills Nephrology Clinics PLLC
Cleveland, MS
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
Brand vs generic prescribing mix · Typical
Michael Portner, MD - brand share 20.0%
Nephrology Physician average
20% brand-name claims vs 80% generic, on 1,271 2024 Medicare Part D claims.
The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2024.
1,271
Total Claims
$578K
Total Drug Cost
136
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,472.867
- Total Day Supply
- 39,241
- Brand vs Generic
- 20% brand / 80% generic
- Brand Drug Cost
- $532K
- Generic Drug Cost
- $46K
- Opioid Claims
- 45 (3.5% rate)
- Antibiotic Claims
- 100
Patient Demographics
- Average Patient Age
- 62.2 years
- Avg HCC Risk Score
- 7.50
- Gender Split
- 50% female / 50% male
- Age Distribution
- <65: 67, 65-74: 46, 75-84: N/A, 85+: N/A
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Michael Portner, MD prescribes most
Top Medicare Part D drugs by claim count, 2024
- Sevelamer Carbonate
Sevelamer Carbonate
189 claims
- Velphoro
Velphoro
121 claims
- Auryxia
Auryxia
98 claims
- Amlodipine Besylate 63
Amlodipine Besylate
63 claims
- Calcium Acetate 38
Calcium Acetate
38 claims
- Ciprofloxacin Hcl 35
Ciprofloxacin Hcl
35 claims
- Gabapentin 33
Gabapentin
33 claims
- Furosemide 31
Furosemide
31 claims
| Drug | Claims |
|---|---|
| Sevelamer Carbonate | 189 |
| Velphoro Sucroferric Oxyhydroxide | 121 |
| Auryxia Ferric Citrate | 98 |
| Amlodipine Besylate | 63 |
| Calcium Acetate | 38 |
| Ciprofloxacin Hcl | 35 |
| Gabapentin | 33 |
| Furosemide | 31 |
| Omeprazole | 31 |
| Megestrol Acetate | 28 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Nephrology Physician Overview
How Michael Portner, MD fits within the Nephrology Physician landscape nationally.
10,806
Nephrology Physician Providers in US
55
States with Nephrology Physician
1,511
Avg Claims per Provider
Michael Portner, MD's 1,271 claims are below the specialty average of 1,511.
Nationwide Nephrology Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Portner, both outside Mississippi so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2006)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Nephrology Physician Providers in Mississippi
Other clinicians with the same primary specialty enrolled in Mississippi, drawn from the same CMS NPPES roster as Portner.
One of 95 Nephrology Physician providers enrolled in Mississippi, 5 are shown here.
Dr. Mohit Ahuja
M.D.
Flowood, MS
Dr. John Andy
M.D.
Meridian, MS
Dr. Mohammad Atari
MD
Jackson, MS
Dr. Uma Mahesh Avula
MD
Flowood, MS
Dr. Calvin Baker
MD
Tupelo, MS
Compare Nephrology Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Michael Portner, MD's specialty? ▼
Michael Portner, MD specializes in Nephrology Physician and practices in Cleveland, Mississippi. Credentials: MD.
How much does Michael Portner, MD prescribe under Medicare Part D? ▼
In 2024, Michael Portner, MD wrote 1,271 Medicare Part D claims totaling $578K in drug costs for 136 beneficiaries.
Where is Michael Portner, MD located? ▼
Michael Portner, MD is located at 803 FIRST STREET, Cleveland, MS, 38732. Phone: (662) 843-2721.
What is Michael Portner, MD's NPI number? ▼
Michael Portner, MD's National Provider Identifier (NPI) is 1659439867, issued on 12/04/2006.
Does Michael Portner, MD prescribe more brand-name or generic drugs? ▼
Michael Portner, MD's prescribing is 20% brand-name and 80% generic drugs by claim count, with $532K in brand drug costs.
Does Michael Portner, MD prescribe opioids? ▼
Yes, Michael Portner, MD had 45 opioid claims in 2024 with an opioid prescribing rate of 3.5%.
How many Nephrology Physician providers are there in the US? ▼
There are 10,806 Nephrology Physician providers across 55 states in the US. The average Nephrology Physician provider writes 1,511 Medicare Part D claims per year.
What drugs does Michael Portner, MD prescribe most often? ▼
Based on 2024 Medicare Part D data, Michael Portner, MD's most frequently prescribed drugs include Sevelamer Carbonate, Velphoro, Auryxia. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Michael Portner, MD accept Medicare? ▼
Michael Portner, MD appears in CMS Medicare data with 1,271 Part D claims and 136 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Michael Portner, MD's credentials? ▼
Michael Portner, MD's NPI is 1659439867 with credentials MD. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.
Data Sources
View source datasets and methodology notes
- Provider Directory
- CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
- Specialty Classification
- NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
- Prescribing Data
- CMS Medicare Part D Prescriber Public Use File (2024). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
- Limitations
- Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.
See our complete data methodology for details on how we collect and process government data.
Data as of August 2026 (NPPES) / 2024 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).
Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of August 2026.