Endoscopic ultrasound guided 22 gauge core needle biopsy for the diagnosis of Autoimmune pancreatitis

Background: It is difficult to obtain adequate tissue sample for diagnosing autoimmune pancreatitis (AIP) with the help of traditional EUS-guided FNA. As per ICDC guidelines, EUS-guided FNA is not recommended for diagnosing AIP(1). We herein present a report of 2 cases of using a new flexible 22 gauge (G) core biopsy needle (SharkCore, Medtronic, Sunnydale, Calif) for diagnosing AIP. Methods: This is a report of 2 cases reviewed retrospectively which had used 22G core biopsy needle for obtaining histo-pathological samples for diagnosing AIP. The cases were reviewed with both endoscopist and a pathologist to determine if the diagnostic criteria were met. Results: Both the cases had adequate tissue sample obtained to make a clear diagnosis of AIP. Pathology showed changes of chronic pancreatitis with atrophy and storiform pattern of fibrosis with a dense lymphoplasmacytic infiltrate in both cases along with identification of IgG4 cells. Conclusion: EUS-guided fine needle biopsy (FNB) using the SharkCore needle can be used reliably for diagnosing AIP. More studies need to be performed to validate this further.