Mary C. Littlejohn, APN
- Medicare patients, 2024
- 313
- Part D claims, 2024
- 391
- MIPS score, 2024
- 100
- Hospital affiliations
- 4
- Medical groups
- 2
- Practice address
- 1 St Elizabeth Blvd, O'Fallon, IL 62269
- Practice phone
- Call (217) 492-9651
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
HSHS St. Elizabeth's Hospital
O'Fallon, Illinois
Find Mary Littlejohn's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Mary C. Littlejohn is a nurse practitioner in O'Fallon, Illinois
Mary Littlejohn practices at HSHS St. Elizabeth's Hospital in O'Fallon, Illinois.
Mary Littlejohn's NPI, 1255779955, was assigned on June 5, 2013. Mary Littlejohn holds Illinois license 209010179.
- NPI
- 1255779955NPI Registry (opens in a new tab)
- Medicare PAC ID
- 3577795806
- NPI enumeration date
- June 5, 2013
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (217) 492-9651
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Female
- Estimated age
- 40
- Medical school graduation
- 2012
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Practice Data; and Doctors and Clinicians National Downloadable File (CMS)
Mary C. Littlejohn practices at HSHS St. Elizabeth's Hospital in O'Fallon, Illinois
Mary Littlejohn's primary practice is HSHS St. Elizabeth's Hospital, at 1 St Elizabeth Blvd, O'Fallon, IL 62269 in Saint Clair County. The practice phone is (217) 492-9651.
- HSHS St. Elizabeth's Hospital1 St Elizabeth Blvd, O'Fallon, IL 62269 · Saint Clair CountyPhone(217) 492-9651
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Mary C. Littlejohn is affiliated with 5 sites of care and 2 medical groups
Mary Littlejohn's primary practice is HSHS St. Elizabeth's Hospital in O'Fallon, Illinois. Mary Littlejohn is also affiliated with HSHS St. Elizabeth's Hospital. The medical group on file is Vituity (formerly CEP America). Dmand AI also links Mary Littlejohn to 3 more hospitals and 1 medical group, each named with a free account.
Sources: NPPES NPI Registry (CMS); Dmand AI Practice Data; Dmand AI Affiliation Data; and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Mary C. Littlejohn's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Mary Littlejohn practices, 4 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| HSHS St. Elizabeth's Hospital | Available with a free account |
| +4 more sites and 1 medical group | Available with a free account |
Source: Dmand AI Technology Install Data
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Mary C. Littlejohn is one of 4,254 nurse practitioners in Illinois
Nurse practitioner is Mary Littlejohn's primary specialty in the NPI Registry, under taxonomy code 363L00000X. Mary Littlejohn is licensed in Illinois.
Specialties and state licenses
- Nurse practitioner, IllinoisPrimary
Nurse practitioners near Mary Littlejohn
Counts of nurse practitioners with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Mary C. Littlejohn treated 313 Medicare patients in 2024, average age 78
CMS counts 313 Medicare patients who saw Mary Littlejohn in 2024. The largest group is 75 to 84, with 109 patients. 75% of them have arthritis, and 75% have high blood pressure. 21% are also on Medicaid. Their average risk score is 2.35, where 1.00 is the Medicare average, so they are sicker than most Medicare patients.
Across all payers, Dmand AI patient panel data puts Mary Littlejohn's median patient age at 72, with 59% women.
Mary Littlejohn's Medicare patients by age, 2024
Mary Littlejohn's Medicare patients by sex, 2024
- Women17355%
- Men14045%
Chronic conditions among Mary Littlejohn's Medicare patients, 2024
- Arthritis75%
- High blood pressure75%
- High cholesterol75%
- Chronic kidney disease61%
- Ischemic heart disease54%
- Heart failure53%
- Diabetes52%
- Anxiety43%
Share of Medicare patients with each condition. A patient can have several.
Mary Littlejohn's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 72
Patient panel by sex, all payers
- Women59%
- Men40%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Mary C. Littlejohn wrote 391 Medicare Part D claims in 2024
In 2024, Mary Littlejohn wrote 391 Medicare Part D claims for 140 patients. 91% of them were for generic drugs.
Mary Littlejohn's Part D claims by kind of drug, 2024
- Generic354 claims91%
- Brand-name and other37 claims9%
Drug classes CMS tracks in Mary Littlejohn's Part D claims, 2024
- Opioids6%24 of 391 claims
- Antibiotics15%57 of 391 claims
- Antipsychotics, patients 65 and over4%15 of 391 claims
Share of all Part D claims for each drug class CMS reports on. Classes with no claims are left out.
Source: Medicare Part D Prescribers - by Provider (CMS), 2024 data
Mary C. Littlejohn scored 100 out of 100 in Medicare's MIPS program for 2024
CMS publishes a Merit-based Incentive Payment System (MIPS) score of 100 out of 100 for Mary Littlejohn for performance year 2024, reported as part of a group. Mary Littlejohn accepts Medicare assignment, so Medicare's approved amount is taken as full payment.
- Accepts Medicare assignment
- Yes
Mary Littlejohn's MIPS scores, performance year 2024
- 100of 100Final score
- 96.6of 100Quality
- 40of 100Improvement Activities
- 82of 100Cost
Each score is out of 100. The final score weighs the categories CMS scored for this clinician.
Sources: Doctors and Clinicians National Downloadable File (CMS); and Clinician Public Reporting: Overall MIPS Performance (CMS), 2024 data, released September 10, 2026
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Sources for Mary C. Littlejohn's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice DataDmand AI Affiliation DataDmand AI Org Hierarchy Data |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab)Clinician Public Reporting: Overall MIPS Performance (CMS) (opens in a new tab) |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Mary C. Littlejohn
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Mary C. Littlejohn's NPI number?
Mary C. Littlejohn's NPI number is 1255779955. It was assigned on June 5, 2013, and it is active in the NPI Registry.
What does Mary C. Littlejohn specialize in?
Mary C. Littlejohn is a nurse practitioner in O'Fallon, Illinois. The primary specialty in the NPI Registry is Nurse Practitioner (taxonomy code 363L00000X).
Where does Mary C. Littlejohn practice?
Mary Littlejohn practices at 1 St Elizabeth Blvd, O'Fallon, IL 62269. Mary Littlejohn's primary practice is HSHS St. Elizabeth's Hospital in O'Fallon, Illinois. Dmand AI also links Mary Littlejohn to 3 hospitals and 1 medical group.
What is Mary C. Littlejohn's office phone number?
The practice phone on file for Mary Littlejohn is (217) 492-9651.
What is Mary C. Littlejohn's medical license number?
Mary Littlejohn holds Illinois license 209010179.
Which hospitals is Mary C. Littlejohn affiliated with?
Mary Littlejohn is affiliated with HSHS St. Elizabeth's Hospital. Dmand AI links Mary Littlejohn to 3 more hospitals.
What medical group is Mary C. Littlejohn part of?
Mary Littlejohn is linked to Vituity (formerly CEP America). Dmand AI links Mary Littlejohn to 1 more medical group.
Does Mary C. Littlejohn accept Medicare?
Yes. CMS lists Mary Littlejohn as accepting Medicare assignment.
What is Mary C. Littlejohn's MIPS score?
Mary Littlejohn's MIPS final score for performance year 2024 is 100 out of 100, reported as part of a group.
How many Medicare patients does Mary C. Littlejohn see?
CMS counts 313 Medicare patients who saw Mary Littlejohn in 2024, with an average age of 78.
How long has Mary C. Littlejohn been practicing?
Mary Littlejohn graduated from medical school in 2012, 14 years ago.
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