Karolina Stack, M.D.
Karolina Stack, M.D. is a Pediatrics Physician in Oshkosh, WI, registered under NPI 1053842443. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 2700 W 9TH AVE STE 211, Oshkosh, WI 54904. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 83243 | WI | Pediatrics Physician primary |
| 1053842243 | IL | Pediatrics Physician |
| 036.151998 | IL | Pediatrics Physician |
Licences are recorded in 2 states: WI, IL. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.
- Status
- Approved
- Provider type
- Practitioner - Pediatric Medicine
- PAC ID
- 4082055421
- Enrollment ID
- I20240515004175
Medicare enrolment is recorded as approved under the provider type Practitioner - Pediatric Medicine. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
Licensed in 2 states
This provider holds licences in 2 states: Illinois and Wisconsin. The practice address on file is in Oshkosh, WI, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.
Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.
What Pediatrics covers
A pediatrician is concerned with the physical, emotional and social health of children from birth to young adulthood. Care encompasses a broad spectrum of health services ranging from preventive healthcare to the diagnosis and treatment of acute and chronic diseases. A pediatrician deals with biological, social and environmental influences on the developing child, and with the impact of disease and dysfunction on development. NUCC Health Care Provider Taxonomy, code 208000000X
All registered taxonomy codes
This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 208000000X | Pediatrics Physician | 83243 | WI | primary |
| 208000000X | Pediatrics Physician | 1053842243 | IL | |
| 208000000X | Pediatrics Physician | 036.151998 | IL |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1053842443 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Mar 27, 2017 |
| Last updated | Jun 30, 2025 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | M.D. |
| Practice address |
2700 W 9TH AVE STE 211 Oshkosh, WI 54904 (920) 223-8000 |
| Other identifiers |
100273308
· Medicaid (WI) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 0 | 5 | 3 | 8 | 4 | 2 | 4 | 4 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 1 | 3 | 7 | 4 | 4 | 4 | 8 |
Sum = 57 · next multiple of 10 = 60 · check digit = 3 · actual last digit = 3
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.