8 weeks of Nexium&Protonix40mg for severe esophagitis & eritemous pangastritis. Now erosive antral gastritis, no esophagitis. Causes & treatment?

Possible Causes. Sounds like you have had a series of endoscopic studies and likely biopsy studies to rule out infection with H. Pylori, Barrett Disease, and Eosinophilic Gastritis. Consider serum Gastrin level, parietal cell antibodies and B12 level. No antiarthritic meds incl. aspirin. No Tums because of acid rebound(looks likes acid is being suppressed) Take Nexium (esomeprazole) in early morn Consider Nexium (esomeprazole)+Carafate+Pepcid.
Gastritis. Esophagitis and erosive antral gastritis is usually caused by excess acid secretion, and is related to stress. The medications will usually help but to not "cure" the problem. Try to identify the stress causes, and see your healthcare provider to refer you to a specialist. Certain bacteria (Heliobacter) can make this condition continue, so another treatment may benefit you.
Severe & Unusual. I am not a gastroenterologist (& u shd consult w/ 1) but it sounds like u have a severe & unusual case. Normally, 8 wks of twice-daily Nexium, (esomeprazole) Protonix, or other PPI shd heal the stomach. If u have an ("erosive") antral ulcer despite PPI, u cd have a tumor, vascular problem, a disease (IBD?) or an infection (H.Pylori?) that kept the stomach from healing despite treatment. Consider HealthTap Prime.