Recent advances in the management of autoimmune pancreatitis in the era of artificial intelligence

Table 1 Characteristics of the two subtypes of autoimmune pancreatitis

Characteristic	AIP-1	AIP-2
Male/female ratio	3/1	1/1
Mean age	65 yr	40 yr
Geographical distribution	Asia > Europe and United States	Europe and United States > Asia
Clinical presentation	Jaundice 60%-80%. Acute pancreatitis 15%. Weight loss 65%	Acute pancreatitis 80%. Jaundice < 30%
Biological presentation	IgG4 > 1.35 g/L (sensitivity 70%, specificity 93%). IgG4 > 2.7 g/L (sensitivity 53%, specificity 99%). Lipase < 3xN. Cholestasis: > 80% of cases. Diabetes: 65% of cases. Insulin-dependent diabetes: 20% of cases. Exocrine pancreatic insufficiency: 40% of cases	Unspecific. Lipase > 3xN. Rare endocrine and exocrine pancreatic insufficiency
Histological criteria	Lymphoplasmacytic infiltration without neutrophils. Storiform fibrosis. Obliterative venulitis. IgG4 plasma cells > 10 in a high-power field	Destruction of inter- and intralobular ducts by neutrophils (granulocytic epithelial lesions). Few or no IgG4 plasma cells
Relapse rate after corticosteroid therapy	> 30%	< 15%

AIP: Autoimmune pancreatitis; IgG: Immunoglobulin G.

Table 2 Summary table of the International Consensus Diagnostic Criteria for autoimmune pancreatitis-1[10]

ICDC	Level 1	Level 2
P: Parenchymal imaging	Typical: Diffuse enlargement with delayed enhancement (rim-like enhancement)	Indeterminate: Segmental or focal enlargement with delayed enhancement
D: Ductal imaging	Single long stricture (> 1/3 length of MPD) or multiple stricture without marked upstream dilatation	Segmental or focal narrowing without marked upstream dilatation (< 5 mm)
S: Serology	IgG4 > 2x upper limit of normal value (> 2.70 g/L)	IgG4 rate: 1-2x upper limit of normal value
OOI: Other organ involvement	Histology of extra-pancreatic organ (3/4)	Histology of extra-pancreatic organ must show both: (1) Periductal lympho-plasmacytic infiltration without granulocyte epithelial lesions; and (2) > 10 cells/HPF of IgG4 positive cells
	Typical radiological evidence: (1) Stenosis of intrahepatic bile duct or proximal and distal common bile duct; and (2) Retroperitoneal fibrosis	Physical or radiological evidence (1/2): (1) Symmetrically enlarged salivary/lachrymal glands; and (2) Radiological renal involvement
H: Pancreatic histology	3/4 criteria	2/4 criteria
Periductal lymphoplasmacytic infiltration without granulocyte epithelial lesions
Obliterative phlebitis
Storiform fibrosis
> 10 cells/HPF of IgG4 positive cells
Rt: Corticosteroid response	Rapid (≤ 2 wk) radiologically demonstrable resolution or marked improvement in pancreatic/extrapancreatic manifestation

HPF: High power field; ICDC: International Consensus Diagnostic Criteria; IgG: Immunoglobulin G; MPD: Main pancreatic duct.

Table 3 Summary table of the International Consensus Diagnostic Criteria for autoimmune pancreatitis-2[10]

ICDC	Level 1	Level 2
P: Parenchymal imaging	Typical: Diffuse enlargement with delayed enhancement (rim-like enhancement)	Indeterminate: Segmental or focal enlargement with delayed enhancement
D: Ductal imaging	Single long stricture (> 1/3 length of MPD) or multiple stricture without marked upstream dilatation	Segmental or focal narrowing without marked upstream dilatation (< 5 mm)
OOI: Other organ involvement		Clinically diagnosed inflammatory bowel disease
H: Pancreatic histology	Both of the following: (1) Granulocytic infiltration of duct wall with or without granulocytic acinar inflammation; and (2) Absent or scant (0-10 cells/HPF) IgG4-positive cells	Both of the following: (1) Granulocytic and lymphoplasmacytic acinar infiltration; and (2) Absent or scant (0-10 cells/HPF) IgG4-positive cells
Rt: Corticosteroid response	Rapid (≤ 2 wk) radiologically demonstrable resolution or marked improvement in manifestations

HPF: High power field; ICDC: International Consensus Diagnostic Criteria; IgG: Immunoglobulin G; MPD: Main pancreatic duct.