Diagnosis of Cholestasis
Clinical diagnosis can be attainted through signs and symptoms of cholestasis. For further diagnosis special investigations can be of help.
- Leucocytosis (increased WBC count) is present in 85% of cases with high poly-morph-nuclear count.
- There may be elevation of serum bilirubin and serum amylase (in 1/3rd of the cases). Serum amylase may be as high as 1000 Somogyi units in acute cases.
- Straight X-ray of the abdomen in supine and in erect posture and an upright chest X-ray study are essential.
- Only 15% of gallstones are radio-opaque. Upright chest X-ray is performed to exclude other conditions of acute abdomen.
- Straight X-ray may indicate gallbladder-intestinal fistula.
- There is no place for oral cholecystography. Intravenous cholangiography may be performed, but it is gradually taken over by cholescintigraphy and ultrasonography.
- This is performed with a derivative of 99mTechnetium-iminodiacetic acid (technetium-IDA scan).
- This is the only specific test for cholestasis and acute cholecystitis.
- After intravenous injection with contrast material is excreted by the liver and extra-hepatic biliary system including the gallbladder.
- In acute cholestasis and acute cholecystitis the gallbladder is not seen in the scan as the gallbladder outlet or the cystic duct is obstructed.
- This test is positive in almost all patients who are actually suffering from acute cholecystitis.
- Obstruction of the hepatic duct or the common bile duct problems is also detectable by this scan but these are more clearly visualized by PTC or ERCP.
- This can detect calculi within the gallbladder as also right upper quadrant mass and enlargement of the bile duct due to obstruction and pancreas enlargement.
Percutaneous transhepatic cholangiography (PTC)
- This investigation shows intra and or extra-hepatic and gallbladder obstruction due to various causes. This should be done in the operation theater, keeping everything ready for surgery, if be needed.
- PTC has largely been replaced by ERCP which has lower complication rate and a greater therapeutic potential.
Endoscopic Retrograde Cholangio-pancreatography (ERCP)
- This is carried out through cannulated fiber-optic duodenoscope. Main indications are jaundice due to obstruction, bile tract problems and pancreatic diseases.