Quick answers
- Does Cristina Castillo-Nelson accept Medicare assignment?
- Yes. Medicare's clinician data says Cristina Castillo-Nelson accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Cristina Castillo-Nelson see?
- In 2024, CMS data shows 202 Original Medicare patients and 1,071 services for Cristina Castillo-Nelson. This counts Original Medicare only and measures volume, not quality.
- What is Cristina Castillo-Nelson's NPI number?
- 1922495456. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Cristina Castillo-Nelson, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 202 |
|---|---|
| Services billed to Medicare | 1,071 |
| Different services or procedures | 95 |
| Participating Medicare provider | Yes |
| Average age of these patients | 74 |
Most frequent services
- Insertion of needle into vein for collection of blood sample (36415)148 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)140 services
- Complete blood cell count (red cells, white blood cell, platelets), automated test (85027)57 services
- Hemoglobin a1c level (83036)49 services
- Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (G0439)46 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol63%
- Arthritis36%
- Diabetes25%
- Anxiety23%
- Ischemic heart disease22%
Hospitals where Cristina Castillo-Nelson works
Medicare's Facility Affiliation Data lists Cristina Castillo-Nelson at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Aspirus Wausau HospitalWausau, WI · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 520030
- St Lukes HospitalDuluth, MN · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 240047
- Tamarack Health Ashland Medical CenterAshland, WI · Critical Access Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 521359
- Tamarack Health Hayward Medical CenterHayward, WI · Critical Access Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 521336
Practice locations
Addresses where Cristina Castillo-Nelson is enrolled with Medicare (CMS data updated October 2, 2026).
- 1615 Maple LnAshland, WI 54806 (715) 682‑5500
- 2201 Lake Shore Dr EAshland, WI 54806 (715) 685‑6600
- 300 Main St WAshland, WI 54806 (715) 685‑2200
- 7665 US Hwy 2Iron River, WI 54847 (715) 372‑5001
Group practices
Medicare enrollment lists Cristina Castillo-Nelson as a member of these groups (CMS data updated October 2, 2026).
- St. Luke's Hospital of Duluth405 clinicians in the group
- The Lakes Community Health Center Inc105 clinicians in the group
- Memorial Medical Center Inc79 clinicians in the group
Specialties
- Family Practiceprimary
Other family doctors in Ashland
Clinicians with the same Medicare primary specialty in Ashland, WI — not a recommendation.
Other clinicians in St. Luke's Hospital of Duluth
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of California, Irvine, California College Of Medicine |
| Graduation year | 2015 (11 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1922495456 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians