Gastroenterology and Hepatology: Bleeding, Inflammation, Cirrhosis and Pancreatitis
Core concepts
Gastroenterology and hepatology require a structured approach to upper and lower GI bleeding, peptic ulcer disease and Helicobacter pylori, inflammatory bowel disease, acute pancreatitis, cirrhosis and its complications, jaundice and abnormal liver tests. In cirrhosis, understand portal hypertension, varices, ascites, spontaneous bacterial peritonitis (SBP), hepatic encephalopathy and hepatorenal syndrome. Ascitic fluid analysis includes cell count, culture and the serum-ascites albumin gradient (SAAG); SAAG at least 11 g/L indicates portal hypertension. Acute pancreatitis diagnosis needs two of three features: characteristic pain, lipase more than three times the upper limit, and imaging.
Traps
Do not diagnose SBP only by culture; an ascitic polymorphonuclear count of at least 250/mm3 is sufficient to treat. A normal lipase does not exclude pancreatitis if presentation is late. NSAIDs and H. pylori are key ulcer risks. In variceal bleeding, give vasoactive therapy and prophylactic antibiotics early, before endoscopy. Beware of over-transfusing in cirrhosis, which can raise portal pressure. Coeliac disease may present with iron deficiency or osteoporosis rather than diarrhoea.
Worked example / rule of thumb
A patient with cirrhosis and ascites has fever and abdominal discomfort. Ascitic fluid PMN count is 400/mm3. Diagnose SBP and start a third-generation cephalosporin plus intravenous albumin (1.5 g/kg on day 1 and 1 g/kg on day 3). Rule: in ascites, a PMN count of at least 250/mm3 means treat for SBP even if culture is pending or negative.