Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

Donald S. Diefendorf, PA-C

Individual provider Medical Physician Assistant · NPI 1437187002

Donald S. Diefendorf, PA-C is a Physician Assistant in Baltimore, Maryland. Qualified in 1998, 28 years ago. Practices with Wellspan Medical Group, a 2,342-clinician group, works from 2 locations, accepts Medicare assignment and offers telehealth. Licensed in Maryland and Pennsylvania.

Years since qualifying
28
Licensed in
MD, PA
In the registry since
2006
Specialties on file
2
What do these letters mean?
PA-C — Physician Assistant, Certified
A physician assistant who holds current national certification.

See every abbreviation used in this directory →

Practice location Address checks out

2700 Quarry Lake Dr Ste 300
Baltimore, MD 21209
Phone: (410) 377-8900
Fax: (410) 377-0576
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 1227 Baltimore St, Hanover, PA 17331-4406 — (717) 812-2055

Specialties & licences

Medical Physician Assistant (primary) Taxonomy 363AM0700X · Licence MA002841L (PA)
Medical Physician Assistant Taxonomy 363AM0700X · Licence C0002134 (MD)

Record details

NPI number1437187002
Entity typeIndividual (Type 1)
GenderMale
Credentials PA-C
Sole proprietorNo
NPI enumeratedJune 30, 2006
Last updated in NPPESDecember 5, 2025
Certification dateDecember 5, 2025

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyPHYSICIAN ASSISTANT
Medical schoolOTHER
Graduated 1998 (28 years in practice)
Group practice Wellspan Medical Group — 2342 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations4 on file with Medicare

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