Jason J. Gass, DO

Medicare activity in 2024

Official CMS public-use data for Jason J. Gass, 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.

Most frequent services

1. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)480 services
2. Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes (99222)194 services
3. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)71 services
4. New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more (99203)16 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 cholesterol75%
• Arthritis67%
• Chronic kidney disease58%
• Anxiety53%
• Depression49%

Hospitals where Jason J. Gass works

Medicare's Facility Affiliation Data lists Jason J. Gass 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.

• Mercy Hospital St LouisSaint Louis, MO · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 260020

Practice locations

Addresses where Jason J. Gass is enrolled with Medicare (CMS data updated October 2, 2026).

• 621 S New Ballas Rd, Suite 7018bSaint Louis, MO 63141 (314) 251‑4949

Group practices

Medicare enrollment lists Jason J. Gass as a member of this group (CMS data updated October 2, 2026).

• Mercy Clinic Infectious Disease LLC4 clinicians in the group

Specialties

• Infectious Diseaseprimary
• Internal Medicinealso

Find other Infectious Disease doctors in Missouri →

Other infectious disease doctors in Saint Louis

Clinicians with the same Medicare primary specialty in Saint Louis, MO — not a recommendation.

• Anupam S. Pande, MD
• Kelsey L. Rowe, MD
• Daniel T. Vo, MD
• Hilary E. Reno, MD
• Max H. David, MD
• Aaloke Mody, MD
• Luis M. Parra-Rodriguez, MD
• Conor F. Grant, MD

All infectious disease doctors in Saint Louis →

Other clinicians in Mercy Clinic Infectious Disease LLC

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

• Jad A. Khoury, MD
• Jin Wang, MD
• Frederick M. Kuhlmann, MD

Clinician information

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

1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
6. Medicare Care Compare — official Medicare tool to look up clinicians