Hepatic, Biliary, & Pancreatic Diseases

Hepatic, Biliary, & Pancreatic Diseases: Decompensation, Infection, and Inflammation

Complications of Cirrhosis and Portal Hypertension

Decompensated cirrhosis presents with manifestations of portal hypertension, including ascites, gastroesophageal varices, and hepatic encephalopathy.

• Ascites: Evaluation requires a diagnostic paracentesis. The serum-to-ascites albumin gradient (SAAG) is calculated by subtracting the ascites albumin concentration from the serum albumin concentration. A SAAG >= 1.1 g/dL indicates portal hypertension (e.g., cirrhosis, congestive heart failure, Budd-Chiari syndrome). A SAAG < 1.1 g/dL indicates non-portal hypertensive causes (e.g., peritoneal carcinomatosis, tuberculous peritonitis, nephrotic syndrome). Management of portal hypertensive ascites includes dietary sodium restriction (<2 g/day) and oral diuretics, typically using a combination of spironolactone and furosemide in a 100:40 ratio to maintain normokalemia. For refractory ascites, large-volume paracentesis (LVP) is performed. If more than 5 liters of fluid is removed, intravenous albumin (6 to 8 grams per liter of fluid removed) must be administered to prevent post-paracentesis circulatory dysfunction.
• Spontaneous Bacterial Peritonitis (SBP): SBP is a bacterial infection of ascites fluid without an apparent intra-abdominal source. It is diagnosed when the ascites fluid neutrophil count (polymorphonuclear leukocytes or PMNs) is >= 250/mm³. Empiric treatment must be started immediately with an intravenous third-generation cephalosporin (such as cefotaxime or ceftriaxone). To prevent hepatorenal syndrome, intravenous albumin (1.5 g/kg on day 1 and 1.0 g/kg on day 3) should be administered, particularly in patients with serum creatinine >1 mg/dL, blood urea nitrogen >30 mg/dL, or total bilirubin >4 mg/dL. Long-term secondary prophylaxis with daily oral ciprofloxacin or trimethoprim-sulfamethoxazole is indicated after the first episode of SBP.
• Gastroesophageal Varices: Screening EGD is mandatory for all patients with newly diagnosed cirrhosis. Primary prophylaxis against variceal bleeding is indicated for patients with medium-to-large varices or small varices with high-risk red wale signs, using either non-selective beta-blockers (nadolol, propranolol, or carvedilol) or endoscopic variceal ligation (EVL). Acute variceal hemorrhage is a medical emergency managed with octreotide infusion, prophylactic ceftriaxone, and urgent EVL within 12 hours. Secondary prophylaxis requires a combination of beta-blocker therapy and repeated EVL until eradication.
• Hepatic Encephalopathy (HE): HE results from neurotoxin accumulation, primarily ammonia, due to portosystemic shunting and impaired hepatic clearance. Management requires identifying and reversing precipitating factors (such as gastrointestinal bleeding, infection, hypokalemia, dehydration, or sedative use). First-line therapy is lactulose, which is metabolized by colonic bacteria to acidify the gut, converting ammonia (NH3) to non-absorbable ammonium (NH4+) and promoting excretion. Titrate lactulose to achieve 2 to 3 soft bowel movements daily. Rifaximin, a non-absorbable antibiotic, is added to lactulose for secondary prevention after a second episode of hepatic encephalopathy.

Biliary Tract Infections: Cholecystitis and Cholangitis

Biliary tract diseases range from localized inflammation to life-threatening systemic infection:

• Acute Cholecystitis: Caused by gallbladder outflow obstruction, usually due to a gallstone impacted in the cystic duct. Patients present with right upper quadrant pain radiating to the scapula, fever, leukocytosis, and a positive Murphy's sign. Right upper quadrant ultrasound is the initial imaging of choice, showing gallstones, gallbladder wall thickening (>4 mm), pericholecystic fluid, and a sonographic Murphy's sign. If ultrasound is equivocal, perform a cholescintigraphy (HIDA) scan; non-visualization of the gallbladder confirms cystic duct obstruction. Management includes intravenous fluids, antibiotics (e.g., ceftriaxone plus metronidazole), and early laparoscopic cholecystectomy, typically within 72 hours of admission.
• Acute Cholangitis: A life-threatening bacterial infection overlaying biliary tract obstruction, commonly due to choledocholithiasis, strictures, or malignancy. It presents as Charcot's triad (fever, right upper quadrant pain, and jaundice) or Reynolds' pentad (Charcot's triad plus hypotension and altered mental status). Labs show leukocytosis, elevated direct bilirubin, and alkaline phosphatase. Initial management involves aggressive resuscitation and broad-spectrum intravenous antibiotics (e.g., piperacillin-tazobactam). Emergent biliary decompression via endoscopic retrograde cholangiopancreatography (ERCP) is mandatory. Cholecystectomy is deferred until the acute infection has resolved and the patient is stable.

Pancreatic Diseases: Acute and Chronic Pancreatitis

• Acute Pancreatitis: Diagnosis requires at least two of the following: acute-onset, severe epigastric pain radiating to the back; serum lipase or amylase elevated to >=3 times the upper limit of normal; and characteristic findings on cross-sectional abdominal imaging. Contrast-enhanced CT scan of the abdomen is not routinely required at presentation if clinical and laboratory findings are diagnostic, but is indicated if the diagnosis is uncertain or if the patient fails to improve after 48 to 72 hours. Gallstones and chronic alcohol abuse are the most common etiologies; other causes include hypertriglyceridemia (>1,000 mg/dL), hypercalcemia, drugs, and post-ERCP. Management centers on aggressive intravenous fluid resuscitation (Lactated Ringer's is preferred over normal saline as it reduces the risk of hyperchloremic metabolic acidosis and systemic inflammatory response), pain control, and early enteral nutrition (within 24 hours) rather than prolonged bowel rest. Prophylactic antibiotics are contraindicated for sterile necrosis; they are reserved for documented pancreatic infection (e.g., gas on CT, positive fine-needle aspiration) using carbapenems.
• Chronic Pancreatitis: Characterized by progressive, irreversible inflammatory damage leading to exocrine and endocrine insufficiency. The classic triad includes pancreatic calcifications (visible on plain radiographs or CT), steatorrhea (due to lipase deficiency), and diabetes mellitus. Diagnosis is confirmed by demonstrating low fecal elastase-1 levels. Management includes lifestyle modification (alcohol and smoking cessation), low-fat diet, and pancreatic enzyme replacement therapy (PERT) containing lipase, protease, and amylase, which must be ingested with every meal and snack.