Pancreatic Ascites (with high amylase and protein)
- If ascites develops in the presence of chronic pancreatic disease (of any etiology), fluid can traverse through diaphragm defects into the pleural space (similar to hepatic hydrothorax)
- Pleural Effusion (see [[Pleural Effusion-Exudate]])
- Pleural Effusion Due to Pancreatico-Pleural Fistula
- External Pancreatic Fistula: pancreatico-cutaneous fistula
- Etiology: trauma, pancreatic disease, or surgery
- Loss of pancreatic fluid (contains 115 mmol bicarbonate per L) can result in metabolic acidosis (see [[Metabolic Acidosis-Normal Anion Gap]])
- Internal Pancreatic Fistula
- First described by Smith (1953), and elaborated upon by Cameron et al. (1976), internal pancreatic fistulas can result in pancreatic ascites, mediastinital pseudocysts, enzymatic mediastinitis, or pancreatic pleural effusions, depending on the flow of pancreatic secretions from a disrupted pancreatic duct or leakage from a pseudocyst.
- Clinical Characteristics: Marked recent weight loss is a major clinical manifestation, and unresponsiveness of the ascites to diuretics is an additional diagnostic clue.
- Pathogenesis: Internal pancreatic fistulas are most commonly cause by disruption of the pancreatic duct due to chronic pancreatitis. The chronic pancreatitis is usually alcoholic in origin in adults, and traumatic in origin in children. They may also be caused by leakage from a pancreatic pseudocyst.
- Anterior disruption of a pseudocyst or a pancreatic duct leads to leakage of pancreatic secretions into the free peritoneal cavity, leading to pancreatic ascites. If the duct is disrupted posteriorly, the secretions leak through the retroperitoneum into the mediastinum via the aortic or esophageal hiatus. Once in the mediastinum, the secretions can either be contained in a mediastinal pseudocyst, lead to enzymatic mediastinitis, or, more commonly, leak through the pleura to enter the chest and form a chronic pancreatic pleural effusion.
- Diagnosis: Pleural or ascitic fluid should be sent for analysis. An elevated amylase level, usually > 1,000 IU/L, with protein levels over 3.0 g/dL is diagnostic. Serum amylase is often elevated as well, due to enzyme diffusion across the peritoneal or pleural surface. Contrast-enhanced computed tomography and endoscopic retrograde cholangiopancreatography (ERCP) may also assist in diagnosis, with the latter an essential component of treatment.
- Treatment: The production of pancreatic enzymes is suppressed by restricting the patient’s oral intake of food patient in conjunction with the use of long-acting somatostatin analogues. The patient’s nutrition is maintained by total parenteral nutrition. This treatment is continued for 2–3 weeks, and the patient is observed for improvement. If no improvement is seen, the patient may be receive endoscopic or surgical treatment. If surgical treatment is followed, an ERCP is needed to identify the site of the leak. Fistulectomy is done in which the involved part of the pancreas is also removed.
Treatment of Pleural Effusion Due to Pancreatic Ascites
- Paracentesis, as required