Pediatric Longitudinal Cohort Study of Chronic Pancreatitis

Inclusion Criteria:

1. All patients/parents must sign an informed consent and/or assent indicating that they are aware of the investigational nature of this study.

2 Patients/parents must have signed an authorization for the release of their or their child's protected health information.

3 All children providing samples should fit the ARP or CP inclusion criteria defined below.

4 All children must be under 18 years of age at the time of enrollment.

Acute pancreatitis (AP): AP is defined as requiring 2 of the following:

1. Abdominal pain compatible with AP,
2. Serum amylase and/or lipase values ≥3 times upper limits of normal,
3. Imaging findings of AP, such as gland enlargement, acute inflammatory changes, and fluid collections.

ARP is defined as:

At least 2 episodes of acute pancreatitis with complete resolution of pain and a \>1 month pain-free interval between episodes.

Chronic Pancreatitis:

Children with at least:

1. One irreversible structural change\* in the pancreas with or without abdominal pain +/- exocrine pancreatic insufficiency +/- diabetes.

\*irreversible structural changes:

* Ductal calculi, dilated side branches, parenchymal calcifications found in any imaging (abdominal ultrasound (abd US), magnetic resonance imaging/magnetic resonance cholangiopancreatography (MRI/MRCP), computerized tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP), endoscopic US (EUS).
* Ductal obstruction or stricture/dilatation/irregularities that are persistent (for \>2 months) on any imaging.
* Parenchymal atrophy, irregular contour, accentuated lobular architecture, cavities alone are not diagnostic findings for CP.
* Surgical or pancreatic biopsy specimen demonstrating histopathologic features compatible with CP (acinar atrophy, fibrosis, protein plugs, infiltration with lymphocytes, plasma cells, macrophages).

Exclusion Criteria:

* Patients must not have any significant medical illnesses that in the investigator's opinion cannot be adequately controlled with appropriate therapy or would compromise the patient's ability to tolerate study interventions.