Complications of Pancreatitis
Complications of acute pancreatitis can be early and late, they can also be separated into locoregional and systematic.
Locoregional complications include
- Pseudocysts – develop in about 10 percent of the cases. It is a collection of pancreatic secretions that are incased in granulation tissue. These cysts can be single or multiple, and they can be located inside or outside the pancreas. In the past surgical operation was the only solution, as these cysts had a very high complication rate. In recent times an ultrasound guided percutaneous catheter drainage is becoming more popular. Currently, morbidity and mortality caused by surgical drainage of pseudocysts is 25% and 5%, respectively.
- Formation of abscess and necrotizing pancreatitis – this complication occurs in about 10-20 percent of the patients. The diagnosis is made using MRI or CT. This complication happens when bacteria are introduced to the necrotic pancreatic tissues. The difference between abscess and necrotizing pancreatitis is that abscess is encapsulated by granulation tissue.
- Sterile necrosis – is usually seen within 10-14 day from the onset of the disease. Contrast-enhanced CT is the main method used to identify this complication. Formation of necrosis is a gradual process, so if the CT is performed too early, it may provide misleading information. After about 4 days the formation of necrosis is finished. The size of the necrosis is a very strong predictor of the mortality in patients with necrotizing pancreatitis.
- Infected necrosis – occur after roughly 10-14 days from the start of the illness. Bacterial contamination of the necrosis greatly increases the rate of mortality. Even though sterile necrosis produces a lot of systematic complications, the mortality rates associated with it are relatively low – 5%-10%. On the other hand, infected necrosis increases the rates of mortality to up to 20%-30%. CT-guided fine-needle aspiration is the main method of diagnosing infected necrosis. If this test has turned out negative, but there is still strong suspicion of bacterial infection, it should be repeated every 4 days. The best time for surgical procedure of the infected necrosis is three to four weeks after the start of the illness. Delaying the operation allows for the patient to stabilize, inflammation to subside, and the delineation between the dead and live tissues to form.
- Vascular complications – occur in up to 25% of the cases of acute pancreatitis. The most common vascular complications are erosions of gastrointestinal vessels, pseudocyst hemorrhage, venous thrombosis, pseudoaneurysm and variceal formation. Mortality associated with hemorrhage is as high as 14.5%.
- Pseudoaneurysm – is a formation of blood clot outside a vessel. It happens in 3.5%-10% of the patients with acute pancreatitis and usually involves pancreaticoduodenal, gastroduodenal, and splenic arteries. When pseudoaneurysm ruptures, the resulting hemorrhage presents a serious threat to the life of the patient. Not only is it hard to diagnose if the pseudoaneurysm has ruptured, it can also lead to death in a matter of minutes or hours in 7.5% of the patients. Angioembolization is the method of choice when treating pseudoaneurysms, since it is a lot less invasive than surgical procedure and produces fewer complications.
- Venous thrombosis – occurs as a result of inflammation near the venous structures. Thrombosis of the splenic vein is the most common, and happens in up to 42% of the patients with acute pancreatitis.
Systemic complications include
- Acute respiratory distress syndrome – is a life-threatening reaction to severe injuries and bacterial infection. It is characterized by inflammation of the tissues of the lungs, which leads to impaired gas exchange. This process causes a hypoxemia and often multiple organ failure. If the patient is untreated, this syndrome has a fatality rate of 90%. With timely, systematic treatment, the mortality rate is still as high as 50%.
- Multiple organ dysfunction syndrome – is a process during which the function of many organs is altered due to serious, life-threatening disease. The homeostasis can only be regained after medical treatment, since the patient’s own strength is depleted.
- Disseminated intravascular coagulation (DIC) – is a process during which multiple blood clots appear within the bloodstream. Not only do these clots obstruct many arteries throughout the body, DIC also depletes the reserves of platelets, which disrupts normal coagulation. Death often occurs due to severe bleeding or multi organ failure.
- Hypocalcaemia - is caused by creation of calcium soaps in the abdominal cavity, along with glucagon-stimulated release of calcitonin and decrease in secretion of parathyroid hormone. This results in numbness of hands and feet, arrhythmias, tetany, and convulsions. This condition can be life-threatening due to severe laryngospasm and cardiac arrhythmias.
- Insulin dependent diabetes mellitus – necrosis of the pancreas usually involves the part that is responsible for excretory functions (production of enzymes); however, if the process is severe, it can also affect the incretory (endocrine) portion of the pancreas, destroying the beta-cells. This leads to acquired Type I diabetes.