Karl T. Mersich, MD

Medicare activity in 2024

Official CMS public-use data for Karl T. Mersich, 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. Pathology examination of tissue using a microscope, intermediate complexity (88305)172 services
2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)73 services
3. Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)54 services
4. Biopsy of large bowel using a flexible endoscope (45380)50 services
5. Special stained specimen slides to identify organisms including interpretation and report (88312)50 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%
• Arthritis59%
• Anxiety35%
• Diabetes31%
• Ischemic heart disease28%

Hospitals where Karl T. Mersich works

Medicare's Facility Affiliation Data lists Karl T. Mersich 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.

• AdventHealth Fish MemorialOrange City, FL · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 100072

Practice locations

Addresses where Karl T. Mersich is enrolled with Medicare (CMS data updated October 2, 2026).

• 2884 Wellness Ave, 100 Gastroenterology of Greater OrlandoOrange City, FL 32763 (386) 668‑2221
• 2884 Wellness Ave, Suite 100Orange City, FL 32763 (386) 668‑2221
• 835 Currency Cir, Suite 1001Lake Mary, FL 32746 (407) 749‑6656

Group practices

Medicare enrollment lists Karl T. Mersich as a member of these groups (CMS data updated October 2, 2026).

• Gastroenterology Associates of Southwest Florida LLC66 clinicians in the group
• Gastro MD Florida, LLC34 clinicians in the group

Specialties

• Gastroenterologyprimary

Find other Gastroenterology doctors in Florida →

Other gastroenterologists in Orange City

Clinicians with the same Medicare primary specialty in Orange City, FL — not a recommendation.

• Ahmed A. Elbanna, DO
• Wei Lu, MD
• Adel Y. Daas, MD
• Miguel J. Salazar, MD
• Vishal Gupta, MD
• Jennifer A. Sinclair, MD

All gastroenterologists in Orange City →

Other clinicians in Gastroenterology Associates of Southwest Florida LLC

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

• Christopher A. Fernandez, MD
• Leia Sullivan, PA
• Teresa Da Cunha, MD
• Keely L. Cook, PA
• Brian D. Feiock, MD
• Jillian Hysko, PA

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