Evaluation of EUS-guided FNA for Diagnosing Autoimmune Pancreatitis
Condition: Autoimmune Pancreatitis
MeSH terms: Pancreatitis; Autoimmune Pancreatitis
Study type: Interventional

Summary: 
      The aim is to evaluate EUS-FNA efficacy for AIP diagnosis using a 22-gauge (G) needle.
    

Detailed description: 
      Patients who suggested having Autoimmune pancreatitis (AIP) and underwent endoscopic
      ultrasound-guided fine needle aspiration (EUS-FNA） by using a standard 22-gauge aspiration
      needle were enrolled between January 2013 and May 2017. The enrollment criteria included age
      greater than 20 years at the time of enrollment; presence of imaging characteristics of AIP,
      as specified in the International Consensus Diagnostic Criteria（ICDC） (diffuse or
      segmental/focal enlargement with delayed enhancement and diffuse or segmental/focal or
      multiple irregular narrowing of the main pancreatic duct without marked upstream dilatation)
      was confirmed by computed tomography (CT), magnetic resonance imaging (MRI), or EUS. The
      exclusion criteria were steroid administration within 3 months before the initiation of
      treatment; refusal or inability to provide informed consent; episode of acute pancreatitis in
      previous 2 weeks; inability to safely perform EUS-FNA, such as cardiorespiratory dysfunction,
      mental diseases, coagulopathy and drug addiction.All procedures were performed under deep
      sedation by a single experienced endosonographer who had performed more than 500 cases.
      EUS-FNA was performed by using Olympus linear echoendoscopes , Diagnostic Ultrasound System
      and 22-G needle . Once the lesion was evaluated by EUS, the echoendoscopist would select the
      shortest pathway, while avoiding blood vessels, to reach the lesion. Under real-time
      visualization, slow-pull technique and suction technique were used to punctured each lesions.
      The specimens were expelled onto glass slides, and then prepared for histological and
      cytological examinations. Because neither pathologists nor cytologists were present on-site
      at our institution, the puncture was repeated until a whitish material could be observed
      macroscopically.Tissue samples were fixed in formalin and embedded in paraffin. A paraffin
      block was thin cut into serial sections and stained with hematoxylin-eosin(H&E). To detect
      infiltrated plasma cells, anti-IgG4 antibody would be done if necessary. The histologic
      analysis was made by an experienced pathologist who was blind to the kinds of studies
      referring to the histological criteria of the ICDC. The Lymphoplasmacytic sclerosing
      pancreatitis (LPSP ) findings are as follow: (1) Periductal lymphoplasmacytic infiltrate
      without granulocytic infiltration; (2) Obliterative phlebitis; (3)Storiform fibrosis; (4)
      Abundant (>10cells/HPF) immunoglobulin G4 (IgG 4)positive cells. The level-1 criteria of LPSP
      were positive for 3 or more of the 4 LPSP findings, and the level-2 criteria were positive
      for 2 of the 4 items. The idiopathic duct-centric chronic pancreatitis (IDCP) findings are as
      follow: (1) Granulocytic infiltration of duct wall (GEL) with or without granulocytic acinar
      inflammation; (2)Granulocytic and lymphoplasmacytic acinar infiltrate; (3)Absent or scant
      (0-10 cells/ High-power fields) IgG4-positive cells. The level-1 criteria of IDCP were
      positive for items (1) and (3), and the level-2 criteria were positive for items (2) and
      (3).Statistical analyses were performed with Statistical Analysis System (SAS) version 9.2.
      All tests were 2-tailed and a P value of less than 0.05 was considered to indicate a
      statistically significant difference. All category variables will be described in terms of
      the count and percentage using the χ 2 test, whereas the continuous variables will be
      described as mean ± standard deviation using τ tests or Wilcoxon rank-sum tests. Outpatients
      were observed for immediate complications in the recovery room for 2 hours and followed up on
      the day after the procedure to monitor for possible complications.
    

Intervention name(s): EUS-FNA
Intervention type(s): Procedure
Intervention description(s): Once the lesion was evaluated by EUS, the echoendoscopist would select the shortest pathway, while avoiding blood vessels, to reach the lesion. Under real-time visualization, slow-pull technique and suction technique were used to punctured each lesions. The specimens were expelled onto glass slides, and then prepared for histological and cytological examinations.
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: AIP; EUS-FNA