Value of anti-plasminogen binding peptide, anti-carbonic anhydrase II, immunoglobulin G4, and other serological markers for the differentiation of autoimmune pancreatitis and pancreatic cancer

Abstract

The diagnosis of autoimmune pancreatitis (AIP) and its differential diagnosis from pancreatic cancer (PC) can be challenging. In this retrospective study, we aimed to evaluate the value of anti-plasminogen binding peptide (a-PBP), immunoglobulin G4 (IgG4), and anti-carbonic anhydrase-II (a-CA-II), together with other serological markers whose value is not fully elucidated.The serum levels of a-PBP, IgG4, IgG, anti-nuclear antibodies (ANA), anti-lactoferrin (a-LF), a-CA-II, and rheumatoid factor (RF) were evaluated in patients with AIP (n = 29), PC (n = 17), pancreatic neuroendocrine neoplasm (P-NEN, n = 12), and alcoholic chronic pancreatitis (ACP, n = 41). ANCA were measured in the AIP patients.There was no statistically significant difference in mean a-PBP values in AIP compared with PC. A ROC curve showed that, when using a cut-off of 38.3 U, low values of a-PBP had a sensitivity and specificity of 45% and 71% for differentiating AIP from PC. The sensitivity and specificity of IgG4 (cut-off 1.4 g/L) for differentiating AIP from PC was 45% and 88%, but rose to 52% and 88% when using a cut-off of 1.09 g/L. When using this cut-off, the sensitivity and specificity for differentiating type 1 AIP from PC was 68% and 88%. None of the other markers were significantly changed in AIP versus PC. For differentiation of type 1 and type 2 AIP, the only significant differences were IgG4 in type 1 AIP (P < .01), with a sensitivity of 68% and a specificity of 80%, and c-ANCA elevations found in some type 2 AIP patients (P < .05).The only serological marker for which we found a statistically significant difference in mean values between AIP and PC was IgG4. However, the value of IgG4 for the distinction of AIP from PC was limited, probably in part due to the relatively high number of type 2 AIP patients in our study. In accord with recent publications, our data do not support a role of increased serum a-PBP for the diagnosis of AIP.

Unraveling the relationship between autoimmune pancreatitis type 2 and inflammatory bowel disease: Results from two centers and systematic review of the literature

“…Interestingly, AIP patients with IBD in our cohort were more likely to have a definite diagnosis compared with studies included in the systematic review, 55% versus 38.0% respectively 13,20–22,42 . In line with the observations of the systematic review, the ratio of UC to CD in our study was 3:1 10,11,13,14,18–33,36–47 . Moreover, the location and behavior of the CD according to the Montreal classification 16 were similar to the results reported by Lorenzo et al., 22 with predominantly non‐stricturing, non‐penetrating disease, located mainly in the colon.…”

Pancreatic Diseases and Microbiota: A Literature Review and Future Perspectives

“…Unfortunately, to date, these findings have not been confirmed. At first, Buijs et al in 2016 [77], and then Detlfsen et al [78] in 2018, did not find significant differences in serum concentrations of anti-PBP antibodies in AIP patients. Furthermore, in the second study the authors investigated the anti-CAII antibodies serum concentration, but no differences were found with the control group.…”

S3-Leitlinie Pankreatitis – Leitlinie der Deutschen Gesellschaft für Gastroenterologie, Verdauungs- und Stoffwechselkrankheiten (DGVS) – September 2021 – AWMF Registernummer 021-003

“…Serum IgG, verschiedene Autoantikörper wie ANA, Anti-Carboanhydrase II, Lactoferrin, Anti-Plasminogen-binding-Peptid) wegen ihrer geringen Spezifität nicht berücksichtigt 780 . Dieses Vorgehen vernachlässigt ebenfalls zahlreiche klinische Fallserien aus Japan und Europa 767 773 776 777 779 781 782 783 784 785 786 und die Erfahrung vorheriger Diagnosesysteme aus Japan 775 , Korea 787 und Italien 773 .…”

“…Serum IgG, verschiede-ne Autoantikörper wie ANA, Anti-Carboanhydrase II, Lactoferrin, Anti-Plasminogen-binding-Peptid) wegen ihrer geringen Spezifität nicht berücksichtigt [780]. Dieses Vorgehen vernachlässigt ebenfalls zahlreiche klinische Fallserien aus Japan und Europa [767,773,776,777,779,[781][782][783][784][785][786] und die Erfahrung vorheriger Diagnosesysteme aus Japan [775], Korea [787] und Italien [773]. Bei Hinweisen auf das Vorliegen einer AIP sind als primäre Untersuchungsverfahren der abdominelle Ultraschall, die CT oder bevorzugt die MRT mit DWI (Diffusionsbildgebung) und die Endosonografie geeignet [750,765,[788][789][790][791][792].…”