The Third Kingdom, Obstructive Jaundice: When the Bile Can’t Get Out

When the pipes are blocked, pressure rises…

In the First Kingdom, bilirubin production was too high.
In the Second, the liver cells were under attack.
But in the Third Kingdom, the liver is doing its job, beautifully, until…

The bile pathway is blocked
Bilirubin is conjugated (water-soluble)…
…but cannot escape into the intestine
So it backflows into the bloodstream 

That’s obstructive jaundice, also called post-hepatic jaundice.

The hallmark features

Dark urine (conjugated bilirubin is water-soluble)
Pale stools (no bile reaching bowel → no stercobilin)
Pruritus, bile salts in the skin (and it REALLY itches)
High ALP + GGT (cholestatic pattern)
Enlarged, non-tender gallbladder → Courvoisier’s law*

* If the gallbladder is palpable in a jaundiced patient — think malignancy, not stones.

Memorise that. Examiners adore it.

So, what blocks the ducts?

To understand causes, think where the obstruction is coming from:

1.Extraluminal compression

→ Something from outside pinches or squeezes the ducts

Common culprits:

• Pancreatic head cancer, #1 cause in older patients
• Periampullary tumours
• Pancreatitis (acute swelling or chronic fibrosis)
• Enlarged lymph nodes (metastatic cancers, lymphoma)
• Mirizzi’s syndrome
  (an impacted stone in the cystic duct compresses the common hepatic duct, surgery viva favourite)

This is like a traffic jam caused by a lorry tipped over on the outside lane.

Clue: Painless jaundice in an elderly patient → malignancy until proven otherwise

2.Intramural obstruction, within the wall

→ Disease of the duct lining itself

• Primary sclerosing cholangitis (PSC)
  Often linked with ulcerative colitis
• Cholangiocarcinoma
  Cancer originating from bile duct epithelium
• Strictures after surgery or trauma
• Inflammatory fibrosis from recurrent cholangitis

These are the “narrowing pipes” problems, not blocked, but tightened.

Clue:
PSC = beading of ducts on imaging + p-ANCA positivity 

3.Intraluminal obstruction, inside the canal

→ Something physically blocks the bile stream

Most common and exam-relevant:

• Gallstones (choledocholithiasis)
• Sludge (infection, stasis)
• Parasites e.g. Clonorchis sinensis, Ascaris lumbricoides
• Intraductal bile duct tumours (rare IPNBs)

Think of this group as plugs or corks inside the pipe itself.

Clues:

• Sudden onset biliary colic
• Jaundice may come and go
• Can progress to ascending cholangitis
  (Charcot’s Triad: fever + RUQ pain + jaundice
  Reynolds’ Pentad adds shock + confusion → surgical emergency!)

Investigations: Find the stone or the stricture

Start simple:
Ultrasound (dilated ducts? gallstones?)
Then escalate:

• MRCP for duct mapping
• ERCP if intervention needed
• CT if malignancy suspected
• EUS for small stones/tumours

ALP + GGT = your cholestatic alarm bells 
ALT/AST may rise modestly too, don’t be fooled by that.

Management, relieve the obstruction

No matter the reason, the treatment goal is the same:
Get bile flowing again

In one sentence for exams

Dark urine + pale stools + ALP/GGT way up = obstructive jaundice until proven otherwise.

And when the gallbladder is palpable?
Think carcinoma, always.