Abdomen and its Contents
Core concepts
This domain covers solid organs, the biliary tree, hernias, and the retroperitoneum. Understand biliary colic versus acute cholecystitis versus choledocholithiasis with cholangitis, the presentation of acute pancreatitis and its severity markers, and the anatomy and complications of inguinal and femoral hernias. Know when imaging (ultrasound first for biliary disease) and intervention (cholecystectomy, ERCP) are indicated.
Traps
- Charcot vs. Reynolds: Charcot's triad (fever, RUQ pain, jaundice) suggests cholangitis; Reynolds' pentad adds hypotension and altered mental status and signals septic cholangitis requiring urgent biliary drainage.
- Femoral vs. inguinal hernia: femoral hernias are more common in women and have a higher strangulation risk; they present below the inguinal ligament. Questions test whether you recognize the higher urgency.
- Pancreatitis severity: don't rely on a single lab value; use clinical trajectory, organ failure, and imaging. Early fluid resuscitation is the cornerstone.
- Gallstone ileus: suspect in elderly patients with SBO and pneumobilia; the stone impacts at the terminal ileum.
Rule of thumb
For suspected acute cholecystitis, ultrasound is the first-line study; for suspected choledocholithiasis with cholangitis, pursue ERCP for drainage and defer elective cholecystectomy until the patient stabilizes.
Worked example
An elderly woman with a painful groin mass below the inguinal ligament and vomiting: suspect an incarcerated femoral hernia. This carries high strangulation risk, so proceed to urgent operative repair rather than watchful waiting.