Biliary Atresia Dr. Altan Alim - PowerPoint Presentation

Slide1

Biliary Atresia

Dr. Altan Alim

Yeditepe

University

Medical

Faculty

Section

of Organ

Transplantation

and

Pediatric

Surgery

Slide2

Introduction

Biliary atresia is characterized by obliteration or discontinuity of the extrahepatic biliary system, resulting in obstruction to bile

flow.

Most common surgically treatable cause of Cholestasis in

newborns

If not corrected



Secondary biliary cirrhosis

Slide3

Embryology

The

biliary system originates from the hepatic diverticulum

of the foregut at 4 weeks

’ gestation

.

This differentiates into cranial

and caudal components, which give rise to the

intrahepatic and

extrahepatic bile ducts, respectively.

Slide4

Groups

Isolated

Biliary Atresia

Associated with

 situs

inversus

or 

polysplenia

/

asplenia

 with or without other congenital anomalies

Postnatal form

Fetal

/embryonic form

Accounts for 65-90% of cases

10-35% of cases.

Slide5

Kasai classification system

Type

I

obliteration

of the

common bile duct

the

proximal ducts are

patent

Type

II

Type

IIa

is atresia of the hepatic duct, with cystic bile ducts found at the porta

hepatis

Type

IIb

is

atresia of the cystic duct, common bile duct, and hepatic ducts

Slide6

Type III

>

90% of

patients

atresia occurs at porta

hepatis

.

Should

not be confused with

intrahepatic biliary hypoplasia

,

Group

of distinct and surgically

noncorrectable

disorders.

Slide7

Slide8

Variants of ductal anatomy in biliary atresia

Slide9

Pathophysiology/Etiology

Multifactorial

Genetic

Inflammatory

infectious

Infectious agents

causing bile duct

obliteration (H/P evidence of inflammatory lesion)

reovirus

type

3

rotavirus

and 

cytomegalovirus

(

CMV)

Slide10

Pathophysiology/Etiology

Other causes include

bile duct ischemia,

abnormal

bile acid metabolism,

pancreaticobiliary

maljunction

environmental toxins

Slide11

Congenital Anomalies Associated with Biliary Atresia

Malrotation

Preduodenal

portal vein

Polysplenia

Interrupted inferior vena cava

Azygous continuation

Cardiac malformations

Slide12

Epidemiology

Highest

in Asian

populations

Biliary atresia occurs in between 1 in 10,000 and 1 in

16,700 live births

More

common in females than in

males

Long -term

survival rate for infants

with

biliary atresia following

portoenterostomy

47-60

% at 5 years

25-35

% at 10

years

The

fetal

/perinatal form is evident within the first 2 weeks of

life.

The

postnatal type presents in infants aged 2-8 weeks.

Slide13

Diagnosis

History

jaundice

,

dark urine, and light stools

.

In most cases,

acholic

stools are not noted at birth but develop over the first few weeks of

life.

Appetite

, growth, and weight gain may be

normal

during the first few weeks of life

.

Slide14

Physical findings

Hepatomegaly may be present early, and the liver is often firm or hard to palpation. 

Splenomegaly is

common,

Enlarging

spleen suggests progressive cirrhosis with portal

hypertension

In

fetal

/neonatal

form (

polysplenia

/

asplenia

syndrome),

midline

liver may be palpated in the epigastrium .

Cardiac murmurs



associated cardiac anomalies

Slide15

Work Up

Labs

Serum bilirubin (total and direct

)

infants

show

only moderate elevations in total bilirubin, which is commonly 6-12 mg/

dL

, with the direct

fraction comprising

50-60% of total serum bilirubin

.

Alkaline

phosphatase (AP), 5'

nucleotidase

, gamma-

glutamyl

transpeptidase

(GGTP), serum aminotransferases, serum bile

acids

Serum alpha1-antitrypsin with Pi

typing:

Alpha1-antitrypsin

deficiency is the most common inherited liver disease that presents with neonatal

cholestasis.

Sweat chloride (Cl):

Biliary

tract involvement

is

a well-recognized complication of cystic fibrosis (CF)

Slide16

Imaging studies

Ultrasonography

 

E

xclude

specific anomalies of the extrahepatic biliary

system, particularly

choledochal

cysts

.

In biliary

atresia it may

demonstrate absence of the gallbladder and no dilatation of the biliary

tree.

sensitivity and

specificity do

not exceed 80%

Slide17

Gallbladder ghost triad

gallbladder length less than 1.9 cm,a thin or indistinct gallbladder wall, an irregular and lobular contour97% sensitive and 100% specific for biliary atresia.

Slide18

Hepatobiliary

scintiscanning

using technetium-labeled

diisopropyl

iminodiacetic

acid (DISIDA) nuclear

scintiscan

,

intestinal

excretion of radiolabel confirms patency of the extrahepatic biliary system

.

If time allows, all jaundiced infants undergoing

hepatobiliary scintigraphy

should be

pretreated

with

phenobarbital (5

mg/kg/day) for 5 days before the study.

sensitivity

of hepatobiliary scintigraphy is high (~100%).

The

specificity is  93% specific, and 94.6% accurate in diagnosing biliary atresia following

pretreatment

with

phenobarbital

Slide19

disadvantages

reliability of the

scintiscan

is diminished at very high conjugated bilirubin levels (>20 mg/

dL

).

10% rate of false-positive or false-negative diagnostic errors

Slide20

MRCP

 incomplete visualization of the extrahepatic biliary

system

sensitivity and specificity of 90% and 77%,

respectively.

Slide21

Endoscopic retrograde

cholangiopancreatography

(ERCP)

Percutaneous liver

biopsy

most

accurate

nonsurgical

diagnostic

test

differentiate between obstructive and hepatocellular causes of cholestasis,

with 90% sensitivity and specificity for biliary

atresia

bile

ductular

proliferation in the liver biopsy is

considered

diagnostic

for biliary atresia

Intraoperative cholangiography

:

demonstrates

anatomy and patency of the extrahepatic biliary tract. 

Slide22

Management

Surgical intervention is the only mechanism for a definitive diagnosis (intraoperative cholangiogram)therapy (Kasai portoenterostomy).

Slide23

When to operate

Goal is to operate

before 70 to 90

days of

life. It is important to note, however, that hepatic

portoenterostomy

is not contraindicated after 90 days of age.

A study of

older children (100 days) revealed acceptable

survival rates

, supporting the use of the procedure, if possible,

even

in

older infants

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