Immune-related enteritis (irEnteritis) clinical, endoscopic, and histological findings (n=19)
| Characteristics | No. of patients |
| Days from ICI therapy initiation to irEnteritis onset, median (IQR) | 138 (50–186) |
| Presenting associated symptoms | |
| Diarrhea | 19 (100%) |
| Abdominal pain | 9 (47%) |
| Nausea/vomiting | 14 (74%) |
| Anorexia/early satiety | 15 (79%) |
| Weight loss (kg) from irEnteritis onset to nadir, median (IQR) | 6 (4–8) |
| Highest CTCAE grade of weight loss | |
| I (<10% total body weight) | 12 (63%) |
| II (10%–20% total body weight) | 5 (26%) |
| III (>20% total body weight) | 2 (11%) |
| Highest CTCAE grade of anorexia* | |
| I | 2 (11%) |
| II | 13 (68%) |
| III | 4 (21%) |
| Highest CTCAE grade of nausea† | |
| I | 2 (11%) |
| II | 14 (74%) |
| III | 3 (15%) |
| Highest CTCAE grade of abdominal pain‡ | |
| None | 4 (21%) |
| I | 3 (16%) |
| II | 12 (63%) |
| Highest CTCAE grade of diarrhea§ | |
| I/II | 15 (79%) |
| III/IV | 4 (21%) |
| Highest CTCAE grade of colitis¶ | |
| I/II | 18 (94%) |
| III/IV | 1 (6%) |
| Pre-OCB fecal calprotectin, median (IQR) (n=10) | 134 (49–241) |
| Post-OCB fecal calprotectin normalization** (n=6) | 5 (86%) |
| Duration (days) of irEnteritis, median (IQR) | 123 (35–182) |
| Hospitalization for irEnteritis | 6 (32%) |
| Adverse events on systemic corticosteroids prior to OCB (n=15) | 6 (40%) |
| Days of continuous steroids prior to OCB, median (IQR) | 46 (15–99) |
| Days from last biological dose to OCB, median (IQR) | 64 (14–158) |
| Days from irEnteritis onset to first endoscopy, median (IQR) | 34 (19–95) |
| Endoscopic evaluation | |
| Sigmoidoscopy only | 2 (11%) |
| EGD only | 4 (21%) |
| Colonoscopy and EGD | 8 (42%) |
| Sigmoidoscopy and EGD | 5 (26%) |
| EGD endoscopic findings (n=17) | |
| Normal | 2 (12%) |
| Gastritis | 3 (18%) |
| Duodenitis | 6 (35%) |
| Gastritis and duodenitis | 5 (29%) |
| Esophagitis, gastritis, and duodenitis | 1 (6%) |
| EGD endoscopic severity (n=17) | |
| Normal mucosa | 5 (29%) |
| Erythema | 4 (24%) |
| Marked erythema and edema | 5 (29%) |
| Erosions/ulcerations | 3 (18%) |
| EGD histological findings (n=17) | |
| Duodenitis | 6 (35%) |
| Gastritis and duodenitis | 9 (53%) |
| Esophagitis, gastritis, and duodenitis | 2 (12%) |
| Lower endoscopy Mayo score (n=15) | |
| 0 | 8 (53%) |
| 1 | 4 (27%) |
| 2 | 3 (20%) |
| Lower endoscopy histological findings (n=15) | |
| Active colitis | 2 (13%) |
| Chronic active colitis | 2 (13%) |
| Microscopic colitis (lymphocytic/collagenous) | 3 (20%) |
| GVHD-like/apoptosis-predominant colitis | 2 (13%) |
| Normal mucosa | 6 (40%) |
| GI toxicity location | |
| Upper GI toxicity alone | 11 (58%) |
| Combined upper and lower GI toxicity | 8 (42%) |
| Small bowel inflammation | |
| Noted on EGD | 17 (89%) |
| Suspected but no EGD | 2 (11%) |
| Treatments for irEnteritis prior to OCB | |
| None/symptomatic | 2 (11%) |
| Systemic corticosteroids | 15 (79%) |
| Standard budesonide | 3 (16%) |
| Biological agents | 4 (21%) |
*Definitions of CTCAE anorexia grading: I—loss of appetite without alteration in eating habits; II—oral intake altered without significant weight loss or malnutrition; III—associated with significant weight loss or malnutrition.
†Definitions of CTCAE nausea grading: I—loss of appetite without alteration in eating habits; II—oral intake decreased without significant weight loss, dehydration, or malnutrition; III—inadequate oral caloric or fluid intake.
‡Definitions of CTCAE abdominal pain grading: I—mild pain; II—moderate pain, limiting instrumental ADL.
§Definitions of CTCAE diarrhea grading: I—increase of <4 stools/day over baseline, II—increase of 4–6 stools/day over baseline, III—increase of ≥7 stools/day over baseline, IV—life-threatening consequences.
¶Definitions of CTCAE colitis grading: I—asymptomatic, clinical or diagnostic observations only; II—abdominal pain, mucus or blood in stool; III—severe abdominal pain, peritoneal signs; IV—life-threatening consequences.
**Normal fecal calprotectin levels are defined by our lab as <50 µg/g.
CTCAE, Common Terminology Criteria for Adverse Events; EGD, esophagogastroduodenoscopy; GVHD, graft-versus-host disease; ICI, immune checkpoint inhibiitor; irEnteritis, immune-related enteritis; OCB, open-capsule budesonide.