Endosc Int Open. 2024 Mar 7;12(3):E332-E338. doi: 10.1055/a-2215-3284. eCollection 2024 Mar.
Early stage AIG의 내시경 특징에 대한 연구 입니다. 최근, 일본에서 AIG 관련 환자의 보고가 많아지고 있고, 과거에는 rare 한 질환으로 알고 있었으나 최근 prevalence 는 서양과 유사하게 올라가고 있습니다. 2023년 진단 criteria for AIG in Japan이 발표되었으나 early stage의 endoscopic findings는 포함되지 않았습니다. 이번 연구는 early stage AIG의 내시경 특징을 살펴보기 위한 연구 입니다.
Patients and methods
<Diagnostic criteria for early-stage AIG: Histologic findings + APCA(or AIFA) positivity>
* The Japanese diagnostic criteria for AIG (early-stage AIG 의 endoscopic findings는 없음)
- Histological findings
: parietal cell/mucous neck cell layer of the oxyntic glands is preserved without interruption
: the remaining parietal cells exhibit degeneration and pseudohypertrophy
: lymphocytic infiltration is observed between the oxyntic glands
: hyperplasia of enterochromaffin-like (ECL) cells is not always present
- Gastric autoantibody positivity
<Patients>
* Include criteria
(1) Positive for serum anti-parietal cell anti body (PCA)
(2) Diagnosed histologically with early-stage AIG
(3) Endoscopically positive for folds on the greater curvature of the gastric corpus
* Exclude
- Severe gastric atrophy with marked vascular visibility and disappearance of folds
* No history of long-term use of proton pump inhibitors
<Laboratory tests>
Serum PCA concentrations: indirect immunofluorescence test (titers ≥ 1:10, positive)
Serum concentrations of anti-H. pylori antibody (H. pylori Ab): enzyme linked immunosorbent or latex immunoturbidimetric assays
* H. pylori infection status
(1) uninfected in patients with no history of H. pylori eradication and H. pylori Ab < 3.0 U/mL
(2) previously infected in patients with a history of H. pylori eradication
(3) currently infected in patients with no history of H. pylori eradication and a H. pylori Ab titer of ≥ 10 U/mL
(4) indeterminate in patients with no history of H. pylori eradication and H. pylori Ab 3.0 to 9.9 U/mL
(Uninfected or currently infected H. pylori status was confirmed based on endoscopic findings.)
<Assessment of endoscopic appearance>
The presence or absence of gastric mucosal atrophy was assessed in the antrum and the lesser and greater curvature of the corpus.
The Kimura-Takemoto classification was not used because the atrophic border could not be clearly determined in most patients in the present study.
<Histopathological evaluations>
Biopsy specimens were obtained from the greater curvature of the upper or middle corpus in all 12 patients and from the greater curvature of the antrum in eight of 12 patients.
Histological gastritis: according to the updated Sydney system
Diagnosed with histological early-stage AIG based on the presence of persisting oxyntic glands damaged by lymphocytic infiltration, and pseudohypertrophy of the remaining parietal cells (Fig. 1).
Figure 1. A representative image of the histopathological findings of early-stage AIG. Pseudohypertrophy of residual parietal cells, exhibiting cytoplasmic protrusion into the lumen (arrows). (Greater curvature of the corpus in Patient 6; hematoxylin and eosin staining).
Results
<Clinical profiles>
The present study enrolled 12 patients, seven men and five women, mean age 56.2 years (range: 41–71 years) (Fig. 2).
* PCA titers: 11명 (≥1:160), 1명 (1:80)
* Gastrin (mean:1350.1pg/mL): 6명 (<1000pg/mL)
* H. pylori: 8명 (uninfected), 3명 (previous infected), 1명 (indeterminate), 0명 (currently infected)
* Autoimmune diseases (3명): 2명 (Basedow’s disease (Graves' disease)), 1명 (type I diabetes)
Figure 2. Clinical profiles and endoscopic findings of the patients included in the present study. (suspected of having AIG are shown with a light blue background)
<Endoscopic findings and histopathological evaluations>
* Endoscopic findings (extent of endoscopic gastric atrophy and associated local appearan) are summarized in Figure 2.
- No atrophic changes in either the antrum or corpus: 3명
- Corpus atrophy: 9명 (7명: No atrophy of greater curvature, 6명: No atrophy of antrum)
* Histopathological evaluations of gastritis are summarized in Table 1.
- Corpus atrophy: No (8명), Mild (4명)
- Corpus inflammtion: Mild (2명), Moderate (9명), Severe (1명)
- Antrum atrophy: Mild (2명, previous infected)
- Antrum inflammation: Mild (1명, previous infected)
- Corpus pseudopyloric metaplasia (10명), Intestinal metadplasia (0명)
Table 1. Histological evaluations of gastritis.
* Bamboo joint-like appearance: 9명
1) Multiple pseudopolyps: 7명 (Fig. 3).
- These pseudopolyps were longitudinally aligned in rows along the long axis of the gastric corpus, which had a bamboo joint-like appearance.
Figure 3. Bamboo joint-like appearance on endoscopy of the patients included in this study. a Patient 7. b Patient 9. c, d Patient 10. e, f Patient 11, presenting with the bamboo joint-like appearance highlighted with indigo carmine dye in f.
2) 2명의 경우, 주름의 부종이 불완전한 분절로 관찰되는 bamboo joint-like 한 얕은 주름 형태로 관찰 됨, Fig. 4b
* Sallmon roe-like appearance: (7명) Edematous mucosa with enlarged gastric areas and erythema, observed in non-atrophic areas of the gastric corpus (Fig. 4). Four of these patients also presented with a bamboo joint-like appearance (▶Fig. 4b).
Figure 4. Salmon roe-like appearance on endoscopy of the patients included in this study. a, b Patient 3, also presenting with a bamboo joint-like appearance (dotted ellipse in b). c Patient 7, showing a close-up view of a salmon roe-like appearance. d Patient 5 (accepted for publication by the Japanese Society of Internal Medicine). e Patient 5, showing a close-up view highlighted with indigo carmine dye. f Patient 6.
* One patient with a previous history of vitamin B12 deficiency was suspected of having AIG, despite presenting with a normal endoscopic appearance (Fig. 5a, Fig. 5b, Fig. 5c) and lacking any of the characteristic endoscopic findings (Patient 1 in ▶Fig. 2). A diagnosis of early-stage AIG in this patient was confirmed by histopathological findings (Fig. 5d) and a high titer of PCA.
Figure 5. A patient with early AIG presenting with a normal endoscopic appearance (Patient 1). a, b, c Endoscopic findings. d Histopathological findings in the greater curvature of the middle corpus, showing oxyntic glands damaged by lymphocytic infiltration (hematoxylin and eosin staining).
Discussion
* Endoscopic findings were the first clues in 11 patients, with the possibility of AIG suggested by a combination of a bamboo joint like or salmon roe-like appearance in the corpus and non atrophic or slightly atrophic antrum.
* When AIG is suspected based on endoscopic findings or hematologic abnormalities, histological and serological studies are required.
* Oxyntic mucosa pseudopolyps: advnaced AIG에서 atrophic change과정에서 남아 있는 oxyntic mucosa의 한 형태로, corpus의 greater curvature와 anterior wall을 따라 longitudinal하게 나타납니다. 미란성 fissure로 인해 proximal stomach의 lesser curvature 에서 longitudinal하게 나타나는 Crohn's disease의 bamboo joint-like 모양과 유사하게 발생하지만, 조직학적으로 lamina propria의 edematous stroma가 보이는 Crohn's disease와는 차이가 있습니다. 또한, 시간이 지나면서 사라진다는 case report 도 있듯이 진행하는 AIG에서 early stage AIG의 내시경 소견으로 볼 수 있겠습니다.
* Salmon roe-like appearance (snake skin (mosaic) pattern): gastric area의 swelling으로 red colored caviar-like gastritis 로 잘 알려진 hypertensive gastropathy의 특징과 유사한 형태의 점막 병변입니다. 또한, current infected H. pylori gastritis의 diffuse redness와도 유사하게 관찰됩니다. 그래서, H. pylori의 current infection이 있으면 AIG에서의 salmon roe-like 병변과의 감별이 어려울 수도 있습니다.
* Serum PCA was strongly positive in 11 of these patients, with titers ≥ 1:160. A recent retrospective study of patients with histologically proven AIG showed that their mean PCA titer was significantly higher during the early or florid phase than during the end phase, suggesting that the progressive destruction of parietal cells and the resultant decrease in the targeted proton pumps could lead to a reduction in PCA titer. The high PCA titers in the present study indicated that these patients retained sufficient parietal cells to be targeted by lymphocytes, a finding confirmed histopathologically.
Conclusions
In conclusion, the present study suggested that the endoscopic findings observed in this series of patients, including bamboo joint-like and salmon roe-like appearances, could be characteristic of early-stage AIG. Studies in large numbers of patients with long-term follow-up are needed to confirm these findings. These results may contribute to determining the overall endoscopic characteristics associated with early-stage AIG.
<Abstract>
Background and study aims
Until recently, autoimmune gastritis (AIG) was usually diagnosed at late stages based on typical endoscopic findings, including corpus-dominant advanced atrophy. Early-stage AIG prior to complete gastric atrophy had rarely been diagnosed due to a lack of knowledge about its endoscopic characteristics. The present study sought to identify the endoscopic characteristics of early-stage AIG, enabling its early diagnosis.
Patients and methods
The clinical and endoscopic findings of 12 patients diagnosed with early-stage AIG between 2016 and 2021 were retrospectively evaluated. Patients were included if they were: (1) positive for serum anti-parietal cell antibody; (2) diagnosed with histological early-stage AIG; and (3) endoscopically positive for folds on the greater curvature of the gastric corpus.
Results
Two characteristic endoscopic findings of early-stage AIG were identified: longitudinal alignment of pseudopolyps (i.e., a bamboo joint-like appearance) and swelling of gastric areas with erythema (i.e., a salmon roe-like appearance).
Conclusions
Endoscopic findings characteristic of early-stage AIG include a bamboo joint-like appearance and a salmon roe-like appearance. Studies in large numbers of patients with long-term follow-up are needed to confirm these findings.
Keywords: autoimmune gastritis, early stage, endoscopy
Endosc Int Open. 2024 Mar 7;12(3):E332-E338. doi: 10.1055/a-2215-3284. eCollection 2024 Mar.
Early stage AIG의 내시경 특징에 대한 연구 입니다. 최근, 일본에서 AIG 관련 환자의 보고가 많아지고 있고, 과거에는 rare 한 질환으로 알고 있었으나 최근 prevalence 는 서양과 유사하게 올라가고 있습니다. 2023년 진단 criteria for AIG in Japan이 발표되었으나 early stage의 endoscopic findings는 포함되지 않았습니다. 이번 연구는 early stage AIG의 내시경 특징을 살펴보기 위한 연구 입니다.
Patients and methods
<Diagnostic criteria for early-stage AIG: Histologic findings + APCA(or AIFA) positivity>
* The Japanese diagnostic criteria for AIG (early-stage AIG 의 endoscopic findings는 없음)
- Histological findings
: parietal cell/mucous neck cell layer of the oxyntic glands is preserved without interruption
: the remaining parietal cells exhibit degeneration and pseudohypertrophy
: lymphocytic infiltration is observed between the oxyntic glands
: hyperplasia of enterochromaffin-like (ECL) cells is not always present
- Gastric autoantibody positivity
<Patients>
* Include criteria
(1) Positive for serum anti-parietal cell anti body (PCA)
(2) Diagnosed histologically with early-stage AIG
(3) Endoscopically positive for folds on the greater curvature of the gastric corpus
* Exclude
- Severe gastric atrophy with marked vascular visibility and disappearance of folds
* No history of long-term use of proton pump inhibitors
<Laboratory tests>
Serum PCA concentrations: indirect immunofluorescence test (titers ≥ 1:10, positive)
Serum concentrations of anti-H. pylori antibody (H. pylori Ab): enzyme linked immunosorbent or latex immunoturbidimetric assays
* H. pylori infection status
(1) uninfected in patients with no history of H. pylori eradication and H. pylori Ab < 3.0 U/mL
(2) previously infected in patients with a history of H. pylori eradication
(3) currently infected in patients with no history of H. pylori eradication and a H. pylori Ab titer of ≥ 10 U/mL
(4) indeterminate in patients with no history of H. pylori eradication and H. pylori Ab 3.0 to 9.9 U/mL
(Uninfected or currently infected H. pylori status was confirmed based on endoscopic findings.)
<Assessment of endoscopic appearance>
The presence or absence of gastric mucosal atrophy was assessed in the antrum and the lesser and greater curvature of the corpus.
The Kimura-Takemoto classification was not used because the atrophic border could not be clearly determined in most patients in the present study.
<Histopathological evaluations>
Biopsy specimens were obtained from the greater curvature of the upper or middle corpus in all 12 patients and from the greater curvature of the antrum in eight of 12 patients.
Histological gastritis: according to the updated Sydney system
Diagnosed with histological early-stage AIG based on the presence of persisting oxyntic glands damaged by lymphocytic infiltration, and pseudohypertrophy of the remaining parietal cells (Fig. 1).
Figure 1. A representative image of the histopathological findings of early-stage AIG. Pseudohypertrophy of residual parietal cells, exhibiting cytoplasmic protrusion into the lumen (arrows). (Greater curvature of the corpus in Patient 6; hematoxylin and eosin staining).
Results
<Clinical profiles>
The present study enrolled 12 patients, seven men and five women, mean age 56.2 years (range: 41–71 years) (Fig. 2).
* PCA titers: 11명 (≥1:160), 1명 (1:80)
* Gastrin (mean:1350.1pg/mL): 6명 (<1000pg/mL)
* H. pylori: 8명 (uninfected), 3명 (previous infected), 1명 (indeterminate), 0명 (currently infected)
* Autoimmune diseases (3명): 2명 (Basedow’s disease (Graves' disease)), 1명 (type I diabetes)
Figure 2. Clinical profiles and endoscopic findings of the patients included in the present study. (suspected of having AIG are shown with a light blue background)
<Endoscopic findings and histopathological evaluations>
* Endoscopic findings (extent of endoscopic gastric atrophy and associated local appearan) are summarized in Figure 2.
- No atrophic changes in either the antrum or corpus: 3명
- Corpus atrophy: 9명 (7명: No atrophy of greater curvature, 6명: No atrophy of antrum)
* Histopathological evaluations of gastritis are summarized in Table 1.
- Corpus atrophy: No (8명), Mild (4명)
- Corpus inflammtion: Mild (2명), Moderate (9명), Severe (1명)
- Antrum atrophy: Mild (2명, previous infected)
- Antrum inflammation: Mild (1명, previous infected)
- Corpus pseudopyloric metaplasia (10명), Intestinal metadplasia (0명)
Table 1. Histological evaluations of gastritis.
* Bamboo joint-like appearance: 9명
1) Multiple pseudopolyps: 7명 (Fig. 3).
- These pseudopolyps were longitudinally aligned in rows along the long axis of the gastric corpus, which had a bamboo joint-like appearance.
Figure 3. Bamboo joint-like appearance on endoscopy of the patients included in this study. a Patient 7. b Patient 9. c, d Patient 10. e, f Patient 11, presenting with the bamboo joint-like appearance highlighted with indigo carmine dye in f.
2) 2명의 경우, 주름의 부종이 불완전한 분절로 관찰되는 bamboo joint-like 한 얕은 주름 형태로 관찰 됨, Fig. 4b
* Sallmon roe-like appearance: (7명) Edematous mucosa with enlarged gastric areas and erythema, observed in non-atrophic areas of the gastric corpus (Fig. 4). Four of these patients also presented with a bamboo joint-like appearance (▶Fig. 4b).
Figure 4. Salmon roe-like appearance on endoscopy of the patients included in this study. a, b Patient 3, also presenting with a bamboo joint-like appearance (dotted ellipse in b). c Patient 7, showing a close-up view of a salmon roe-like appearance. d Patient 5 (accepted for publication by the Japanese Society of Internal Medicine). e Patient 5, showing a close-up view highlighted with indigo carmine dye. f Patient 6.
* One patient with a previous history of vitamin B12 deficiency was suspected of having AIG, despite presenting with a normal endoscopic appearance (Fig. 5a, Fig. 5b, Fig. 5c) and lacking any of the characteristic endoscopic findings (Patient 1 in ▶Fig. 2). A diagnosis of early-stage AIG in this patient was confirmed by histopathological findings (Fig. 5d) and a high titer of PCA.
Figure 5. A patient with early AIG presenting with a normal endoscopic appearance (Patient 1). a, b, c Endoscopic findings. d Histopathological findings in the greater curvature of the middle corpus, showing oxyntic glands damaged by lymphocytic infiltration (hematoxylin and eosin staining).
Discussion
* Endoscopic findings were the first clues in 11 patients, with the possibility of AIG suggested by a combination of a bamboo joint like or salmon roe-like appearance in the corpus and non atrophic or slightly atrophic antrum.
* When AIG is suspected based on endoscopic findings or hematologic abnormalities, histological and serological studies are required.
* Oxyntic mucosa pseudopolyps: advnaced AIG에서 atrophic change과정에서 남아 있는 oxyntic mucosa의 한 형태로, corpus의 greater curvature와 anterior wall을 따라 longitudinal하게 나타납니다. 미란성 fissure로 인해 proximal stomach의 lesser curvature 에서 longitudinal하게 나타나는 Crohn's disease의 bamboo joint-like 모양과 유사하게 발생하지만, 조직학적으로 lamina propria의 edematous stroma가 보이는 Crohn's disease와는 차이가 있습니다. 또한, 시간이 지나면서 사라진다는 case report 도 있듯이 진행하는 AIG에서 early stage AIG의 내시경 소견으로 볼 수 있겠습니다.
* Salmon roe-like appearance (snake skin (mosaic) pattern): gastric area의 swelling으로 red colored caviar-like gastritis 로 잘 알려진 hypertensive gastropathy의 특징과 유사한 형태의 점막 병변입니다. 또한, current infected H. pylori gastritis의 diffuse redness와도 유사하게 관찰됩니다. 그래서, H. pylori의 current infection이 있으면 AIG에서의 salmon roe-like 병변과의 감별이 어려울 수도 있습니다.
* Serum PCA was strongly positive in 11 of these patients, with titers ≥ 1:160. A recent retrospective study of patients with histologically proven AIG showed that their mean PCA titer was significantly higher during the early or florid phase than during the end phase, suggesting that the progressive destruction of parietal cells and the resultant decrease in the targeted proton pumps could lead to a reduction in PCA titer. The high PCA titers in the present study indicated that these patients retained sufficient parietal cells to be targeted by lymphocytes, a finding confirmed histopathologically.
Conclusions
In conclusion, the present study suggested that the endoscopic findings observed in this series of patients, including bamboo joint-like and salmon roe-like appearances, could be characteristic of early-stage AIG. Studies in large numbers of patients with long-term follow-up are needed to confirm these findings. These results may contribute to determining the overall endoscopic characteristics associated with early-stage AIG.
<Abstract>
Background and study aims
Until recently, autoimmune gastritis (AIG) was usually diagnosed at late stages based on typical endoscopic findings, including corpus-dominant advanced atrophy. Early-stage AIG prior to complete gastric atrophy had rarely been diagnosed due to a lack of knowledge about its endoscopic characteristics. The present study sought to identify the endoscopic characteristics of early-stage AIG, enabling its early diagnosis.
Patients and methods
The clinical and endoscopic findings of 12 patients diagnosed with early-stage AIG between 2016 and 2021 were retrospectively evaluated. Patients were included if they were: (1) positive for serum anti-parietal cell antibody; (2) diagnosed with histological early-stage AIG; and (3) endoscopically positive for folds on the greater curvature of the gastric corpus.
Results
Two characteristic endoscopic findings of early-stage AIG were identified: longitudinal alignment of pseudopolyps (i.e., a bamboo joint-like appearance) and swelling of gastric areas with erythema (i.e., a salmon roe-like appearance).
Conclusions
Endoscopic findings characteristic of early-stage AIG include a bamboo joint-like appearance and a salmon roe-like appearance. Studies in large numbers of patients with long-term follow-up are needed to confirm these findings.
Keywords: autoimmune gastritis, early stage, endoscopy