Acronym for Biliary Atresia Spleen Malformation

See Congenital biliary atresia

Represents the so-called embryonic or malformative form of congenital biliary atresia (between 10 and 20 % of cases). No gene appears to be associated with this form of biliary atresia: it could be the result of the interaction of one or more extrinsic factors  with a genetic predisposition occurring at a key time in intrauterine development.

This form of biliary atresia is more common in girls and is associated with other abnormalities such as:

• a splenic abnormality (77 %) : polysplenia, double spleen, asplenia
• a preduodenal portal vein (61 %)
• the absence of the inferior vena cava (39 %) with the subdiaphragmatic venous system draining into the superior vena cava via the azygos vein
• a cardiac defect: VSD; Tetralogy of Fallot, ductus arteriosus
• isomerism (see this term) with an abdominal situs inversus

In addition,  a hepatopulmonary syndrome (see this term) appears earlier in this form of biliary atresia (median age: 22 months of age)

Anesthetic implications: 

• neonatal period: check liver function; it is generally still normal at the time of the Kasai's procedure; and the combination of general anesthesia and thoracic epidural analgesia gives excellent results.
• later: check liver function and hemostasis; risk of portal hypertension; risk of low blood platelets count in case of splenomegaly: frequent malnutrition and osteopenia if ADEK and nutritional vitamin supplements are not given
• echocardiography: malformation ? hepatopulmonary syndrome ?

References:

-          Khalil BA, Perera MT, Mirza DF.
Clinical practice: management of biliary atresia.
Eur J Pediatr 2010; 169:395-402.

-        Davenport M, Tizzard SA, Underhill J, Mieli-Vergani G et al.
The biliary atresia splenic malformation syndrome: a 28-year single-center retrospective study.
J Pediatr 2006; 149:393-400.

Updated: February 2021