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Overview of Chronic Pancreatitis

Definition and Anatomy

• Chronic pancreatitis is characterized by chronic inflammation leading to anatomical alterations in the pancreas, including fibrosis and calcification, resulting in dysfunction of both exocrine and endocrine functions.

Etiology

• The primary cause of chronic pancreatitis is alcohol consumption, with a threshold of 40-50 grams per day being significant for risk. This contrasts with acute pancreatitis, which is often due to biliary causes.

• A mnemonic for remembering the etiologies includes "TIGARO," where T stands for toxic metabolic factors like alcohol, renal failure, hypercalcemia, dyslipidemia, and tobacco use as contributing factors.

Specific Types and Genetic Factors

Tropical Pancreatitis

• Tropical pancreatitis is prevalent in underdeveloped countries and associated with chronic malnutrition; it’s important to recognize this when discussing global health issues.

Genetic Causes

• Genetic mutations (e.g., SPINK1 gene) can predispose individuals to chronic pancreatitis by triggering pancreatic enzyme activation and subsequent autoimmune inflammation. This condition may also present with recurrent acute episodes or obstructive causes.

Pathogenesis of Chronic Pancreatitis

Morphological Changes

• Key pathological features include pancreatic fibrosis and calcification; these changes are critical for diagnosing chronic pancreatitis as they are not seen in acute cases. Fibrosis combined with lymphoplasmacytic infiltration indicates autoimmune origins.

Symptoms Presentation

• Patients typically experience moderate abdominal pain located in the epigastric region that radiates around the torso; this pain worsens after consuming fatty meals but improves when leaning forward. Unlike acute cases, the pain intensity is less severe.

Diagnostic Criteria

Clinical Signs

• Diagnosis involves assessing abdominal pain alongside symptoms such as steatorrhea (fatty stools), which results from exocrine dysfunction due to impaired lipase activity leading to fat malabsorption. Diabetes may also develop due to endocrine dysfunction affecting insulin production from pancreatic beta cells.

Diagnostic Tests

• The most sensitive test for evaluating pancreatic function is the secretin stimulation test; normal amylase/lipase levels help differentiate between chronic conditions versus acute exacerbations where these enzymes would be elevated significantly (>three times normal). Additionally, alkaline phosphatase levels may rise due to duct obstruction during chronic conditions.

Pancreatitis Diagnosis and Treatment Overview

Diagnostic Criteria for Pancreatitis

• The levels of tripsinogen are low, while secretin is sensitive; this specificity aids in clinical diagnosis.

• Initial imaging tests include CT scans, which are essential for examining the retroperitoneum. Remember that CT is sensitive but not specific.

• The cholangiopancreatography (CEPRE) is considered the gold standard for diagnosing chronic pancreatitis, revealing stenosis in both biliary and pancreatic ducts. It serves both diagnostic and therapeutic purposes.

Initial Management Strategies

• General lifestyle changes are crucial, including abstaining from alcohol and tobacco to improve patient outcomes.

• The first line of treatment involves enzymatic replacement therapy, specifically administering pancreatic lipase with meals to alleviate symptoms like abdominal pain.

Pain Management Protocol

• If pain persists despite initial measures, analgesics such as NSAIDs should be used as a first-line option; severe cases may require opioids like morphine or fentanyl.

• In cases where pain remains unmanageable, consider a celiac ganglion block as an advanced intervention strategy.

Advanced Therapeutic Options

• If conservative management fails, endoscopic therapies such as papillotomy or stent placement can help relieve persistent symptoms by dilating ducts.

• Surgical options become necessary when pain is intolerable or complications arise (e.g., fistulas or pseudocysts). Two main surgical approaches exist: resection techniques and drainage techniques based on duct conditions.

Surgical Techniques Explained

• Resection techniques are indicated when the main pancreatic duct is narrowed (<5 mm), while drainage techniques apply when it’s dilated (e.g., performing a pancreatojejunostomy). The classic Whipple procedure may also be utilized in certain cases involving pancreatic cancer treatment contexts.