Gastrointestinal · Year 2 · from Gastrointestinal
Case 1: Jaundice - Distinguishing Causes
Patient Presentation
Demographics: 55-year-old male
Chief Complaint: Yellow skin and eyes for 2 weeks with dark urine and pale stools
History of Present Illness: The patient noticed progressive yellowing of his eyes and skin over the past 2 weeks. His urine has become dark "like tea," and his stools have become pale and clay-colored. He has generalized itching, worse at night. He denies abdominal pain but reports a 10-pound weight loss over 2 months with decreased appetite.
Past Medical History: Type 2 diabetes, new diagnosis 6 months ago (unintentional)
Social History: Never smoked, social alcohol (1-2 drinks/week)
Physical Examination
- Vital Signs: Normal
- General: Jaundiced male, appears uncomfortable from pruritus
- HEENT: Icteric sclerae
- Abdomen: Non-tender, no hepatomegaly; palpable, non-tender gallbladder (Courvoisier's sign positive)
- Skin: Jaundice, excoriations from scratching
Workup and Results
- Liver Function Tests: Total bilirubin 14.2 mg/dL, direct bilirubin 11.8 mg/dL (conjugated hyperbilirubinemia), ALP 485 U/L (markedly elevated), GGT 320 U/L, AST 68 U/L, ALT 72 U/L
- CBC: Normal
- Abdominal Ultrasound: Dilated intrahepatic and extrahepatic bile ducts (CBD 14 mm); no gallstones; pancreatic head mass visualized
- CT Abdomen with Pancreas Protocol: 3.5 cm mass in pancreatic head; dilated bile duct and pancreatic duct ("double duct sign"); liver metastases present
CT scan demonstrating the "double duct sign" - simultaneous dilation of both the common bile duct and pancreatic duct (arrows) - highly suggestive of pancreatic head malignancy causing obstruction.
Image Source: Case courtesy of Radiopaedia.org
Diagnosis
Obstructive (Posthepatic) Jaundice Secondary to Pancreatic Head Adenocarcinoma
Clinical Correlation to Hepatobiliary Physiology
Bilirubin, the end product of heme degradation, is transported to the liver bound to albumin, where hepatocytes take it up, conjugate it with glucuronic acid (making it water-soluble), and excrete it into bile canaliculi. In posthepatic (obstructive) jaundice, conjugated bilirubin cannot be excreted into the duodenum. The cholestatic pattern (markedly elevated ALP and GGT with modest transaminase elevation) indicates bile duct obstruction. Dark urine occurs because water-soluble conjugated bilirubin is renally excreted. Pale stools result from absence of bilirubin reaching the intestine (no urobilinogen formed). Pruritus is caused by bile salt deposition in skin. Courvoisier's sign (palpable, non-tender gallbladder) suggests malignant obstruction, as chronically diseased gallbladders (from stones) do not distend.
Treatment
- ERCP with biliary stent placement for symptomatic relief of jaundice
- Given metastatic disease: palliative chemotherapy (FOLFIRINOX or gemcitabine/nab-paclitaxel)
- Symptom management: cholestyramine for pruritus
- Palliative care consultation