Complications

Local complications

• should be suspected in the presence of
  • persistent abdominal pain
  • serum pancreatic enzyme levels increase despite treatment
  • organ failure that lasts for more than one week
  • clinical signs of sepsis
• imaging (computed tomography) should be carried out to identify local complications
  • first CT done to assess severity should be performed 6-10 days after admission in patients with persistent systemic inflammatory response syndrome or organ failure
  • CT scoring system is not superior to clinical scoring systems in predicting severity
• fluid collections and areas of necrosis maybe identified early (<4 weeks) or late (>4 weeks)
• local complications include
  • acute peripancreatic fluid collection
    • associated with acute interstitial oedematous pancreatitis
    • there is peripancreatic fluid but no necrosis
    • may be single or multiple
    • usually develop in the early phase of pancreatitis
    • most remain uninfected and usually resolves spontaneously
    • the term is applicable only within the first 4 weeks after onset of interstitial edematous pancreatitis and without features of a pseudocyst
  • pancreatic pseudocyst
    • appears as peripancreatic (sometimes intrapancreatic) collection of fluid with a well defined wall with minimal or no necrosis
    • if an acute peripancreatic fluid collection does not resolve spontaneously, it could develop into a pseudocyst
    • associated with both acute interstitial oedematous pancreatitis or necrotizing pancreatitis
    • usually occurs > 4 weeks after onset of pancreatitis
  • acute necrotic collection
    • collections (solid and inhomogeneous components) seen in necrotizing pancreatitis in the first 4 weeks
  • walled-off necrosis
    • a sequelae of acute necrotic collection
    • is a mature well encapsulated collection
    • usually occurs >4 weeks after onset of necrotising pancreatitis
• these collections maysterile or infected
• other local complications may include bowel necrosis, thrombosis of the splenic/portal vein, and gastric emptying malfunction (1,2)

Atlanta classification defines systemic complications as exacerbations of preexisting comorbidities such as chronic lung disease, chronic liver disease, or congestive heart failure or recognizing the failure of respiratory, cardiovascular, and renal organ systems (2). Systemic complications range from minor pyrexia to rapidly fatal, multiple organ-system failure. They include:

• circulatory shock - kinin activation, haemorrhage
• disseminated intravascular coagulation
• respiratory insufficiency:
  • mild e.g. hypoxaemia, atelectasis, pleural effusion
  • severe e.g. adult respiratory distress syndrome
• acute renal failure
• metabolic:
  • hypocalcaemia
  • hyperglycaemia / diabetes mellitus
  • hypertriglyceridaemia
• pancreatic encephalopathy - confusions, delusions, coma
• retinal arteriolar obstruction causing sudden blindness
  • Purtscher's retinopathy
• metastatic fat necrosis

Reference:

• (1) Johnson CD, Besselink MG, Carter R. Acute pancreatitis. BMJ. 2014;349:g4859
• (2) Sureka B et al. Imaging lexicon for acute pancreatitis: 2012 Atlanta Classification revisited. Gastroenterol Rep (Oxf). 2016;4(1):16-23