Transcript OVERVIEW OF DISORDERS OF THE BILIARY TRACT IN CHILDREN

OVERVIEW OF DISORDERS
OF THE BILIARY TRACT IN
CHILDREN
Aswad H. Al.Obeidy
FICMS, FICMS GE&Hep
Kirkuk General Hospital
OVERVIEW OF DISORDERS OF THE BILIARY
TRACT IN CHILDREN
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Cholestatic liver disease results from processes
that interfere with either bile formation by
hepatocytes or bile flow through the intrahepatic
and extrahepatic biliary trees
A number of these disorders result from
defective ontogenesis as well as from a failure of
postnatal adaptation to the extrauterine
environment
The general features of the many cholestatic
liver diseases in the neonate are similar, and a
central problem of pediatric hepatology is
differentiating intrahepatic from extrahepatic
cholestasis
OVERVIEW OF DISORDERS OF THE BILIARY
TRACT IN CHILDREN
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The treatment of metabolic or infective
liver diseases and the surgical
management of biliary anomalies require
early diagnosis
Even when effective treatment is not
possible, infants and children with
progressive liver disease benefit from
optimal nutritional support and medical
management of chronic liver disease
before they are referred for hepatic
transplantation
Disorders of the Biliary Tract in Infants and Children
Cholangiopathies
Extrahepatic biliary atresia
Choledochal cysts
Spontaneous perforation of the common bile duct
Mucous plug syndrome
Sclerosing cholangitis (neonatal, inflammatory bowel disease–
associated, immunodeficiency)
Paucity of intrahepatic bile ducts (syndromic and nonsyndromic)
Caroli's disease
Cystic fibrosis
Biliary helminthiasis
Idiopathic bile duct stricture (possibly congenital)
Post-traumatic common duct stricture
Bile duct tumors (intrinsic and extrinsic)
Bile duct obstruction due to pancreatic disease (inflammatory or
neoplastic)
Graft-versus-host disease
Allograft rejection
Disorders of the gallbladderAnomalies
Cholelithiasis
Acute cholecystitis
Chronic cholecystitis
Acalculous cholecystitis
Acute hydrops of the gallbladderTumors
Relative Frequencies of Various Forms of Neonatal
Cholestasis
Disorder
Cumula. Percentage
Idiopathic neonatal hepatitis
30-35
Extrahepatic biliary atresia
30
Alpha1-antitrypsin deficiency
7-10
Intrahepatic cholestatic syndromes (Alagille syndrome, Byler's
disease, others)
5-6
Choledochal cyst
2-4
Bacterial sepsis
2
Hepatitis (cytomegalovirus, rubella, herpes, others)
3-5
Endocrinopathy (hypothyroidism, panhypopituitarism)≈1
Galactosemia
≈1
Inborn errors of bile acid metabolism
≈1O
Other metabolic disorders
≈1
OVERVIEW OF DISORDERS OF THE BILIARY
TRACT IN CHILDREN
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Because of the immaturity of hepatobiliary function, the number
of distinct disorders that exhibit cholestatic jaundice may be
greater during the neonatal period than at any other time of life
Liver dysfunction in the infant, regardless of the cause, is
commonly associated with bile secretory failure and cholestatic
jaundice
Although cholestasis may be traced to the level of the
hepatocyte or the biliary apparatus, in practice there may be
considerable overlap among disorders with regard to the initial
and subsequent sites of injury
Furthermore, another common histologic variable that often
accompanies neonatal cholestasis is bile ductular paucity, or a
diminution in the number of interlobular bile ducts
Serial liver biopsy specimens usually show a progressive drop
in the number of bile ductules per portal tract, with a varying
amount of associated inflammation
DIAGNOSIS OF BILIARY TRACT DISEASE IN INFANTS AND
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CHILDREN
In most infants with cholestatic liver disease, the condition
appears during the first few weeks of life
Differentiating conjugated hyperbilirubinemia from the common
unconjugated, physiologic hyperbilirubinemia of the neonate or
the prolonged jaundice occasionally associated with breastfeeding is essential
The possibility of liver or biliary tract disease must be
considered in any jaundiced neonate older than 14 days
The stools of a patient with well-established biliary atresia are
acholic; however, early in the course of incomplete or evolving
biliary obstruction, the stools may appear normally or only
intermittently pigmented
Life-threatening but treatable disorders such as bacterial
infection and a number of inborn errors of metabolism must be
excluded
Furthermore, the success of surgical procedures in relieving
the biliary obstruction of biliary atresia or a choledochal cyst
depends on early diagnosis and surgery
Evaluation of the Infant with
Cholestasis
History and physical examinationInclude
 Details of family history
 Pregnancy
 Presence of extrahepatic anomalies
 Stool color
Tests to establish the presence and
severity of liver disease
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Fractionated serum bilirubin analysis
Liver biochemical tests (AST, ALT, alkaline
phosphatase, 5′ nucleotidase, gamma
glutamyl transpeptidase)
Tests of liver function (prothrombin time,
partial thromboplastin time, coagulation
factors, serum albumin level, serum
ammonia level, serum cholesterol level,
blood glucose)
Tests for infection
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Complete blood count
Bacterial and viral cultures of blood,
urine, and other sites if indicated
Paracentesis if ascites is present
Serologic tests (for hepatitis B, TORCH
agents, syphilis, EBV, others)
Metabolic studies
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Urine for reducing substances
Alpha1-antitrypsin level and phenotype
Sweat chloride analysis
Metabolic screen (urine and serum amino acids,
urine organic acids)
Thyroid hormone, thyroid-stimulating hormone
(evaluation of hypopituitarism as indicated)
Serum iron and ferritin
Urine and serum analyses of bile acids and bile
acid precursors
Red blood cell galactose-1-phosphate uridyl
transferase activity
Imaging studies
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Ultrasonography of the liver and biliary
tract
Hepatobiliary scintigraphy
Radiography of the long bones and skull
for congenital infection and of the chest
for lung and cardiac disease
Magnetic resonance cholangiography
Percutaneous or endoscopic
cholangiography (rarely indicated)
Procedures
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Duodenal intubation to assess fluid for
bile pigment
Percutaneous liver biopsy (for light and
electron microscopic examination,
enzymologic evaluation)
Bone marrow examination and skin
fibroblast culture for suspected storage
disease
Exploratory laparotomy and intraoperative
cholangiography
Ultrasonography
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Can be used to assess the size and echogenicity of the liver
Even in neonates, high-frequency, real-time ultrasonography
can usually define the presence and size of the gallbladder,
detect stones and sludge in the bile ducts and gallbladder,
and demonstrate cystic or obstructive dilatation of the
biliary system
Extrahepatic anomalies also may be identified
A triangular cord or band-like periportal echogenicity (3 mm
or greater in thickness), which represents a cone-shaped
fibrotic mass cranial to the portal vein, appears to be a
specific ultrasonographic finding in the early diagnosis of
biliary atresia
The gallbladder “ghost” triad, defined as gallbladder length
of less than 1.9 cm, lack of a smooth (complete) echogenic
mucosal lining, and an indistinct wall and irregular or
lobular contour, has also been proposed as a criterion for
biliary atresia
Magnetic resonance cholangiography
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Performed with T2-weighted turbo spin-echo sequences, is
widely used to assess the biliary tract in all age groups
In a 1999 study, MRC reliably demonstrated the common bile
duct and gallbladder in normal neonates
In some patients with biliary atresia, nonvisualization of the
common bile duct and demonstration of a small gallbladder
have been characteristic MRC findings
A subsequent study found that MRC is 82% accurate, 90%
sensitive, and 77% specific for depicting extrahepatic biliary
atresia
Contrary to previous reports, falsepositive and false-negative
findings occur with MRC
Differentiating severe intrahepatic cholestasis from biliary
atresia may be difficult because delineation of the extrahepatic
biliary tree by MRC depends on bile flow
Percutaneous transhepatic
cholangiography
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May be of value in visualizing the biliary tract in select patients
However, the technique is more difficult to perform in infants
than in adults, because the intrahepatic bile ducts are small and
most disorders that occur in infants do not result in dilatation of
the biliary tree
Endoscopic retrograde cholangiopancreatography (ERCP) may
be useful in evaluating children with extrahepatic biliary
obstruction and has been performed successfully in a small
number of cholestatic neonates
Considerable technical exper-tise is required of the endoscopist
to complete this procedure in infants
General anesthesia is needed in most neonates for a
satisfactory examination
Percutaneous liver biopsy
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Is particularly valuable in evaluating cholestatic
patients and can be performed in even the
smallest infants with only sedation and local
anesthesia
A diagnosis of extrahepatic biliary atresia can be
made on the basis of clinical and histologic
criteria in 90% to 95% of patients
When doubt about the diagnosis persists, the
patency of the biliary tree can be evaluated
directly by a minilaparotomy and operative
cholangiogram