Diagnosis and management of pancreatic fistulae resulting in pancreatic ascites or pleural effusions in the era of helical CT and magnetic resonance imaging.

Objectives: Diagnosis of internal pancreatic fistulae (IPF) resulting in ascites or pleural effusions may be facilitated by multislice helical CT-scan and MR-pancreatography [MRP]). Conservative treatment with parenteral nutrition and somatostatin analogues (+/- pancreatic stenting) yields varying results. We aimed to evaluate the usefulness of helical CT and MRP in the diagnosis of IPF. The outcome of patients when the following stepwise treatment algorithm is applied is also descried: i) conservative (enteral nutrition and somatostatin analogues); ii) endoscopic stenting; iii) surgery.

Methods: Sixteen consecutive patients (13 M; median age 42 (14-54) yrs) with chronic pancreatitis (alcoholic 15, hereditary 1) and an IPF were prospectively included between March-01 to December-03. All serous effusions (ascites, N=10; pleural effusion, N=6) contained high lipase [median: 7800 (506-59000) U/mL]. Patients with fistulae communicating with pancreatic pseudocysts were not included.

Results: The diagnosis of IPF and its site were determined in 12/16 patients by CT and 14/15 patients by MRP (site of rupture: head: N=5; isthmus: N=5; body-tail: N=6) and confirmed by ERCP or surgery in 9. Localized atrophy of pancreatic parenchyma adjacent to pancreatic duct rupture was observed in 12 patients (75%). The median follow-up was 30 months (18-51). Early surgery was required in 3 patients (2 with infection of serous fluid at initial aspiration analysis). Thirteen entered the treatment algorithm: - seven patients responded favorably (54%) to conservative treatment (enteral nutrition and somatostatin analogues); - pancreatic stenting, possible in 4 of 6 patients, was successful in closing the IPF in 2; - surgery was required in the 4 remaining patients. Preoperative localization of the rupture site was possible in all patients using non-invasive imaging thus guiding elective intervention in all patients requiring surgery.

Conclusion: Helical CT scan and MRP are useful in localizing MPD rupture sites and fistulae and may obviate the need for pancreatic opacification. A systematic treatment algorithm can be safely used starting with medical strategies (enteral nutrition safely replacing the parenteral route) progressing to endoscopy and finally surgery. Overall about 44% of patients require surgery initially or at follow-up.