Biliary Atresia More Common in Preterm Infants

During my fellowship, one of the faculty presented an abstract indicating that 4 out of 40 preterm infants with cholestasis had significant underlying liver disease in addition to parenteral nutrition associated cholestasis (PNAC).  One of these patients had biliary atresia.  The obvious point was not to assume that the cholestasis was due to the usual suspects found with premature infants.

A recent study indicates that biliary atresia (BA) in Taiwan is more common in preterm infants than in term infants (J Pediatr 2013; 163: 100-3).  The authors identified 197 cases (166 term infants) of BA between 2004-2010. This retrospective study used a nationwide screening for BA (the national stool card registry center database) along with reports from surgeons of the Taiwan Biliary Atresia Study Group.

Results:

  • Annual incidence of BA per 10,000 live births was 1.43 and 2.37 for term and preterm infants respectively.
  • Kasai operation before 60 days occurred in 68.7% of term and 44.4% of preterm infants.  Mean age of Kasai was 52.9 days for term infants and 71.8 for preterm infants.
  • Major congenital anomalies along with BA were more common among preterm (18.5%) than term (4.1%).
  • Mean onset of clay-colored stools among preterm infants was 33.6 days compared with 29.6 for term infants.
  • Stool cards had good sensitivity in detecting BA in both preterm and term infants: 96.3% and 92.8% respectively.
  • Jaundice-free at 3 months following Kasai was 62% of term infants and 37% of preterm infants.
  • 18-month survival with native liver was 72.7% in term infants and 50% in preterm infants.

While the authors point out several studies that have shown prematurity is an independent risk factor associated with BA, nevertheless this idea is counter to conventional wisdom that BA patients are typically well-appearing term infants at the time of diagnosis.  The authors also note that despite delayed diagnosis in preterm infants, this was not correlated with an impact on jaundice-free status 3 months following surgery.  This finding, in particular, should be cautiously interpreted as there were only 27 infants in the preterm group.

Related blog posts:

Outcomes of Biliary Atresia

A retrospective study from the Netherlands showed that timely surgery and postoperative antibiotics were associated with better outcomes in Biliary Atresia (BA) (J Pediatr 2012; 160: 638-44).  While these results are not surprising, due to the length of the study period (1987-2008) and the number of patients (n=214), the study offers insight into a number of unresolved issues with regard to BA.

The type of BA in this series:

  • type I      14  (6.5%)
  • type II      27 (12.6%)
  • type III   172 (80.4%)
  • undetermined  1 (0.9%)

Other notable findings:

  • 10% of their patients had splenic malformations; no significant change in outcome was noted in this subgroup.
  • 18% received high-dose corticosteroids –no benefit was identified in this subgroup.  The authors state that previous studies are inconclusive; a large US trial of prednisolone (4 mg/kg/day initially) is pending.
  • 31% received ursodeoxycholic acid –no benefit was identified in this subgroup.
  • Overall survival improved a little during the study period, mostly due to increased availability of liver transplantation. 4-year transplant-free survival was 46% and 4-year overall survival was 73%.   Table II (pg 641) in their study lists six other international studies.  Recent studies in some countries have reported 4-year survivals of 82-91%.
  • Antibiotic usage (most commonly co-trimoxazole) was associated with improved outcomes, presumably due to less frequent bouts of cholangitis.  Yet, in this study the reported incidence of cholangitis was not lower.  The authors do not have an explanation for this finding.

Age at time of Kasai:

  • ≤45 days 19%
  • 46-60 days 37%
  • 61-89 days 36%
  • ≥90 days 8%
  • Median was 59 days.  Authors note that Netherland guidelines call for all infants with jaundice at 3 weeks to have a fractionated bilirubin.

Related blog entries:

Minimizing malnutrition in Biliary Atresia

The heart connection

MicroRNAs and biliary atresia

Additional references:

  • -JPGN 2010; 51: 631.  n=91.  Operation w/in 100 days.  Data suggesting that 60 day cutoff is not valid. (Hong Kong)
  • -J Pediatr Surg 2003; 38: 997-1000. n=735.  90 day cutoff was key with 5-yr & 10-yr survival. (Japan)
  • -JPGN 2010; 51:61.  Canadian experience. n=230.  Center size did not affect outcome.  Overall 39% at 4yrs had survival with native liver.
  • -Liver transplantation 2009; 15: 829, 876.  With combo of Kasai & Tx, >95% exteneded survival (previously 100% fatal).  >80% will need a liver Tx at some point –~50% before age 2.  Increased fibrosis & genes for fibrosis may increase risk for poor outcome.
  • -JPGN 2009; 48: 72.  Review of 13 year experience. n=91.
  • -Pediatrics 2008; 121: e1438.  Single center (Australia?) noted longer delay in dx of BA over 15-year period from 48.5 days (1990-94) to 59.5 (95-99) to 69 days (2000-2004).
  • -JPGN 2008; 46: 238, 299.  More data on age of dx of BA and outcomes from Sweden.
  • -J Pediatr 2006; 149: 393.  Long term outcome of BA -28yrs in England.  7/56 survived long term with native liver; 5-yr native liver survival was 46%, 10-yr was 32%.
  • -J Pediatr 2006; 148: 467, 432..  Outcome of BA in US.  Avg age of referral was 53 days and HPE avg at 61 days.  one-third will survive to age 10 with native liver; overall 90% survival with kasai/hpe & Tx; 50-60% clear jaundice p Kasai.  yellow alert campaign: www.childliverdisease.org/jaundice
  • -Clin Gastro & Hep 2006; 1411.  BA with choledochal cyst. Nice pics of types of BA. Japanese pathologic classification:  Type 1 with atresia after gallbladder (CBD), type II atresia of common hepatic duct/CBD/GB  c normal intrahepatic ducts, Type III atresia of entire ductal system.
  • -Pediartics 2006; 117: 1147.  Usefulness of stool color cards for screening program.
  • -J Pediatr 2005; 147: 142 & 180-5.  23% c BA survive c native liver for more than 20 yrs; 88% survival for 3 yrs p-OLT; risk factors for poor outcome discussed including poor nutrition & age <5 months.
  • -J Pediatr 2004; 144: 123-5.  severity of fibrosis at time of Kasai inversely correlated with survival
  • -JPGN 2003; 37: 430-33.  Residual fibrosis/cirrhosis noted in 54%/40% respectively of pts with normal labs, median age 13 yrs.
  • -JPGN 2003; 37: 4-21. Review of BA