INVESTIGATIONS AND THEIR RATIONALE

IN OBSTRUCTIVE JAUNDICE

INTRODUCTION

Jaundice, or icterus, is a yellowish discoloration of tissue resulting from the deposition of bilirubin.

Tissue deposition of bilirubin occurs only in the presence of serum hyperbilirubinemia and is a sign of either liver disease or, less often, a hemolytic disorder

I. INDIRECT HYPERBILIRUBINEMIA

A. Hemolytic disorders1. Inheriteda. Spherocytosis, elliptocytosisGlucose-6-phosphate dehydrogenase and pyruvate kinase deficienciesb. Sickle cell anemia2. Acquireda. Microangiopathic hemolytic anemiasb. Paroxysmal nocturnal hemoglobinuriac. Spur cell anemiad. Immune hemolyticB. Ineffective erythropoiesis1. Cobalamin, folate, thalassemia, and severe iron deficienciesC. Drugs1. Rifampicin, probenecid, ribavirinD. Inherited conditions1. Crigler-Najjar types I and II 2. Gilbert's syndromeII. DIRECT HYPERBILIRUBINEMIAA. Inherited conditions B. Acquired conditions C. Extra hepatic obstrn1. Dubin-Johnson syndrome2. Rotor's syndrome

CAUSES

Intrahepaticextrahepatic

intraductal extraductal Cirrhosis

Hepatitis

Drugs Neoplasm

Stone disease

Biliary stricture

Parasites

PSC

Aids related

cholangiopathy

Biliary TB

Secondary

to neoplasm

Pancreatitis

Cystic duct

stones

drugs

cholestasis

gallstone

Acute

cholestatic

injury

Hepatocellular

necrosis

• Anabolic steroids• chlorpromazine

• Thiazide diuretics

• amoxyclav

• Acetaminophen• isoniazid

Typically, drug-induced jaundice appears early with

associated pruritus, but the patient's well-being shows

little alteration.

Generally, symptoms subside promptly when the

offending drug is removed

Clinical classification Of Obstructive Jaundice(Benjamin Classification)

Type I : Complete obstruction

Classical symptoms with biochemical changes

Tumors : Ca. head of PancreasLigation of the CBDCholangio carcinoma Parenchymal Liver diseases

Type II : Intermittent obstructionSymptoms and typical biochemical changes But jaundice may or may not be present

CholedocholithiasisPeriampullary tumorDuodenal diverticula Choledochal CystPapillomas of the bile duct Intra biliary parasitesHemobilia

TYPE III : Chronic incomplete obstructionWith or without classical symptoms but pathologicalchanges are present in bile duct and liver Strictures of the CBD

CongenitalTraumaticSclerosing cholangitis Post radiotherapy

Stenosed biliary enteric anastamosisCystic fibrosisChronic pancreatitis Stenosis of the Sphincter of Oddi

TYPE IV : Segmental Obstruction

one or more segment of intrahepatic biliary tract is obstructed

TraumaticSclerosing cholangitisIntra hepatic stonesCholangio carcinoma

INVESTIGATIONS IN OBSTRUCTIVE JAUNDICE

LABORATORY INVESTIGATIONS

RADIOLOGICAL INVESTIGATIONS

Goals

of investigations

Determine level of

obstruction

Severity of jaundice

Ductal dilatation

jaundice

Cause of

obstruction

ROUTINE INVESTIGATIONS

1. HB

2. TLC

3. DLC

4. RFT ( serum urea, serum creatinine, serum sodium, serum potassium )

5.BLOOD SUGAR

TESTS FOR ASSESSMENT OF LIVER FUNCTION

Tests for liver functioning

Based on

detoxification

& excretory

function

Enzymes

indicating

liver injury

Measure

biosynthetic

function

Damage to

hepatocytescholestasis

Serum

bilirubin

Urine

bilirubin

Blood

ammonia Aspartate

aminotransferase

Alanine

aminotransferase

Alkaline

phosphatase

5 nucleotidase

GGT

Serum albumin

Serum globulin

Coagulation

factors

BilirubinRise by 25-43 micromol/litre/day

Mechanism of hyperbilirubinemia

--- Biliary venous & biliary regurgitation of conjugated bilirubin due to

disruption of tight intracellular junction

--- Trans hepatocytic regurgitation due to reversal of the secretory

polarity of hepatocytes

--- Rupture of dilated canaliculi in to sinusoids due to necrosis of

hepatocytes

BILIRUBIN METABOLISM

SGOT AND SGPT LEVELS

SGOT (AST)/ ASPARTATE TRANSAMINASE

* Marker for hepatocellular toxicity

* Along with ALT is considered biomarker for liver health* Non specific* 2 isoenzymes* Normal Values….

MALES 8-40 IU/L

FEMALES 6-34 IU/L

SGPT ( ALT ) / ALANINE AMINOTRANSFERASE

* Better predictor of hepatic injury than SGOT alone

* Significant elevations in HEPATITIS INFECTIOUS MONONUCLEOSISCHF

* NORMAL VALUES IN MALES < 50 IU/LFEMALES < 32 IU/L

ALKALINE PHOSPHATSE

*Most sensitive indicator Of EXTRA HEPATIC BILIARY OBSTRUCTION

* Factor responsible are

Biliary component regurgitation

Increase in hepatic synthesis

* Biliary component is secreted by BILIARY DUCTULAR ENDOTHELIUM

* Normal range 20-140 IU/L

* May remain elevated for a long time even after the obstruction is

relieved

GAMMA GLUTAMYL TRANSFERASE & 5’NUCLEOTIDASE

GGT

* Predominantly used as a marker for liver diseases* enhanced sensitivity for detection of BILIARY OBSTRUCTION if correlated with ALKALINE PHOSPHATASE* NORMAL VALUE 0-51 IU/L

5’ NUCLEOTIDASE

* An enzyme synthesized in liver* Values if grossly elevated is indicative of biliary obstruction* NORMAL VALUE 2-17 UNITS/L

Measure biosynthetic function

serum albuminnormal value 3.5 – 5.5 gm /dl

prothrombin timenormal value 12 – 14 sec

URINE ANALYSIS

1 Bile salts2 Bile pigments3 Urobilinogen

STOOL EXAMINATION

1 Occult blood

RADIOLOGICAL EVALUATION OF BILIARY TRACTINTRA OP METHODSPRE OPERATIVE METHODS

PLAIN ABDOMINAL X RAY

ABDOMINAL USG

ENDOSCOPIC USG

CT

M R C P

ERCP

PTC

BILIARY SCINTILLOGRAPHY

PER OP CHOLANGIOGRAPHY

INTRA OP BILIARY ENDOSCOPY

LAPROSCOPIC USG

IMAGING GOALS

* To confirm the presence of an extrahepatic obstruction

* To determine the level of the obstruction

* To identify the specific cause of the obstruction

* To provide complementary information relating to the underlying diagnosis (eg., Staging information in cases of malignancy).

* What is the best therapeutic approach

PLAIN X RAY

* Cholelithiasis in 10-20 % of patients with radio opaque stones

* Radiolucent gas in a BI and TRI RADIATE FISSURE, in centre of stone

* May sometimes show rare cases of calcification of GB (PORCELAIN GB )

* Gas in wall of GB ( EMPHYSEMATOUS CHOLECYSTITIS)

* SPECKLED CALCIFICATION in the head of pancreas suggestive of CHRONIC PANCREATITIS

* DUCT DILATATION WILL NOT BE REVEALED IN PLAIN FILMS

RADIO OPAQUE STONES IN GALL BALDDER

PORCELAIN GALL BLADDER

GAS IN GALL BLADDER AND ITS WALLS

ABDOMINAL ULTRASONOGRAPHY

* Is the initial imaging modality of choice as - it is accurate- readily available - quick to perform- inexpensive

OPERATOR DEPENDANT AND MAY GIVE SUBOPTIMAL RESULTS DUE TO EXCESSIVE BODY FAT AND BOWEL GAS

* Biliary obstruction is characterized by BILIARY DILATATION

THIS DILATATION MAY BE CONSPICUOUSLY ABSENT IN 15 % OF PATIENTS

* Prospective evaluation of USG suggests that level of obstruction can be defined in 90 % of the cases

* COLOR FLOW DOPPLER SONOGRAPHY may assist in distinguishing dilated ducts from Portal venous and Hepatic arterial branches

* Provides useful information about the nature and etiology of BILIARY OBSTRUCTION

* Mass lesion visualization is possible

THE RELIABILITY WITH WHICH A BENIGN DISEASE MAY BE DISTINGUISHED FROM A MALIGNANT PROCESS REMAINS UNCLEAR

*Upper limits of normal diameter of CBD-8mmCHD-6mm

ENDOSCOPIC ULTRASOUND (EUS)

Combines Endoscopy and US

Higher-frequency ultrasonic waves compared to traditional US (3.5 MHz vs. 20 MHz) and allows diagnostic tissue sampling via EUS-guided fine-needle aspiration (EUS-FNA).

EUS has been reported to have up to a 98% diagnostic accuracy in patients with obstructive jaundice

The sensitivity of EUS for the identification of focal mass lesions in pancreas has been reported to be superior to that of CT scanning, both traditional and spiral, particularly for tumors smaller than 3 cm in diameter.

Compared to MRCP for the diagnosis of biliary stricture, EUS has been reported to be more specific (100% vs. 76%) and to have a much greater positive predictive value (100% vs. 25%), although the two have equal sensitivity (67%).

The positive yield of eus-fna for cytology in patients with malignant obstruction has been reported to be as high as 96%.

Endoscopic ultrasonography.

CBD, common bile duct; PD, pancreatic duct.

COMPUTED TOMOGRAPHY

* Unlike USG CT is less affected by body habitus and is less operator dependant

* It allows visualisation of the liver,bile ducts, gall bladder and pancreas and is particularlyuseful in detecting hepatic and pancreatic lesions andis the modality of choice in the staging of cancers of the liver,gall bladder, bile ducts and pancreas.

* It can identify the extentof the primary tumour and defines its relationship to otherorgans and blood vessels

*Improvements in CT technology, such as multidetector scanners,which allow for three-dimensional reconstruction of thebiliary tree have led to greater diagnostic accuracy and haveincreased the accuracy of CT in assessing benign disease.

Computed tomography scan demonstrating a gallstonewithin the gall bladder (arrowed).

Computed tomography scan demonstrating a hilar mass.

Intraductal stones appear as target sign on ct CT. 75-88% sensitive, 97%specific for Choledocholithiasis79%sensitive, 100% specific for gallstones

.

MAGNETIC RESONANCE CHOLANGIOPANCREATOGRAPHY (MRCP)

•Noninvasive test to visualize the hepato biliary tree

•No contrast

•Fluid found in the biliary tree is hyper intense on T2-weighted images.

Surrounding structures do not enhance and can be suppressed during image

analysis.

•Sensitive in detecting biliary and pancreatic duct stones, strictures, or dilatations

within the biliary system.

•MRCP combined with conventional MR imaging of the abdomen can provide

information about surrounding structures (eg, pseudocysts, masses).

• ERCP and MRCP similarly effective in detecting malignant hilar and perihilar

obstruction

• MRCP is better able to determine the extent and type of tumor as compared to

ERCP

Absolute contraindications cardiac pacemakercerebral aneurysm clipsocular or cochlear implants

Fluid stasis in the adjacent duodenum or ascitic fluid may produce image artifacts on MRCP, making it difficult to clearly visualize the biliary tree.

MRCP Showing Choledocholithiasis

MRCP is also highly

accurate

MRCP sensitivity

88-92%, specificity

91-98% in detecting

Choledocholithiasis

Endoscopic retrograde cholangiopancreatography (ERCP )

Its an invasive procedure and has therapeutic potential.

Allows biopsy or brush cytology

Stone extraction or stenting

COMPLICATIONS Pancreatitis

Cholangitis

Hemorrhage

Sepsis

CONTRAINDICATIONS Unfavorable anatomy

Pseudo cyst

Red a/c pancreatitis

ERCP film showing Choledocholithiasis

Endoscopic retrograde cholangiopancreatography: partialocclusion of the bile duct by a malignant stricture

Percutaneous Transhepatic Cholangiography (PTC)

PTC is indicated when Percutaneous intervention is needed and ERCP either is inappropriate or has failed.

Can be used to drain biliary obstructions.

Transhepatic cholangiogram showing a stricture of thecommon hepatic duct

Radioisotope scanning

* Technetium-99m (99mTc)-labelled derivatives of iminodiaceticacid (HIDA, IODIDA) when injected intravenously are selectivelytaken up by the retroendothelial cells of the liver andexcreted into the bile.

* This allows for visualisation of the biliarytree and gall bladder. In 90 per cent of normal individuals thegall bladder is visualised within 30 minutes following injectionwith 100 per cent being seen within 1 hour

* Non-visualisation of the gall bladder is suggestive of acutecholecystitis. If the patient has a contracted gall bladder as oftenseen in chronic cholecystitis, the gall bladder visualisation maybe reduced or delayed.

*Biliary scintigraphy may also be helpful in diagnosing bileleaks and iatrogenic biliary obstruction.

It can identify and quantitate the leak thus helping the surgeondetermine whether or not an operative or conservative approachis warranted

Dimethyl iminodiacetic acid (HIDA) scan.

INTRA OPERATIVE TECHNIQUES

A. PER OPERATIVE CHOLANGIOGRAPHY

* During open or laparoscopic cholecystectomy, a catheter can beplaced in the cystic duct and contrast injected directly into thebiliary tree. The technique defines the anatomy and in the mainis used to exclude the presence of stones within the bile ducts

*A single x-ray plate or imageintensifier can be used to obtain and review the images intraoperatively

*In addition, care should betaken when injecting contrast not to introduce air bubbles intothe system as these may give the appearance of stones and leadto a false-positive result

Normal common bile duct: gentle The common bile duct is dilated infusion of contrast with multiple Stoneswhich passes without hindranceinto the duodenum.

Operative biliary endoscopy (choledochoscopy)

* At operation, a flexible fibre optic endoscope can be passed viathe cystic duct into the common bile duct enabling stone identificationand removal under direct vision

* The technique canbe combined with an x-ray image intensifier to ensure completeclearance of the biliary tree.

* After exploration of the bile duct,a tube can be left in the cystic duct remnant or in the commonbile duct (a T-tube) and drainage of the biliary tree established

*After 7–10 days, a track will be established. This track can beused for the passage of a choledochoscope to remove residualstones in the awake patient in an endoscopy suite.

LAPROSCOPIC ULTRASONOGRAPHY

* At laparoscopy the use of laparoscopic probe can be used to image the extra hepatic biliary system

* Useful in BILIARY & PANCREATIC tumor staging and identify the primary tumors and determine its relationship to the major vessels such as hepatic artery, superior mesenteric artery , portal vein and superior mesenteric vein