Table 1.

Summary of previous reports regarding early AIG.

Author	Year	Country	Case No.	Sex	Age	Endoscopic Features	PCA	IFA	Ga. (pg/mL)	PG1 (ng/mL)	PG1/2
Kotera et al. [39]	2020	Japan	1	Male	48	a-1	640×	−	709	unk	unk
			2	Female	70	a-2	640×	+	5265	unk	unk
Ayaki et al. [37]	2021	Japan	1	Female	40	b-1	640×	unk	894	unk	unk
			2	Female	35	b-2	160×	unk	1804	unk	unk
Kishino et al. [38]	2021	Japan	1	Female	50	c	320×	−	820	72.7	4.1
Kotera et al. [40]	2022	Japan	1	Male	66	d	320×	+	338	56.1	7.6

AIG, autoimmune gastritis; PCA, parietal cell antibody; IFA, intrinsic factor antibody; Ga, gastrin; PG, pepsinogen; unk, unknown. a-1: Mild mucosal atrophy and nodules on the greater curvature of the corpus. a-2: Mild mucosal atrophy and nodules on the greater curvature of the corpus. b-1: Polygonal areae gastricae surrounded by a reticular border in a mosaic-like pattern were observed on the greater curvature of the gastric body and fundus. b-2: Non-atrophic mucosa with a mosaic pattern, slight swelling of the areae gastricae, and the presence of erythema in the corpus. c: Reddened and edematous change in the gastric areas, extensively in the gastric fundic gland mucosa without atrophic change. d: Neither atrophic nor inflammatory changes were observed.