Hepatic Hilar Lymph Node Reactivity at Kasai Portoenterostomy for Biliary Atresia: Correlations With Age, Outcome, and Histology of Proximal Biliary Remnant

We hypothesized that if infection is the proximate cause of congenital biliary atresia, an appropriate response to antigen would occur in lymph nodes contiguous with the biliary remnant. We compared the number of follicular germinal centers (GC) in 79 surgically excised hilar lymph nodes (LN) and 27 incidentally discovered cystic duct lymph nodes (CDLN) in 84 subjects at the time of hepatic portoenterostomy (HPE) for biliary atresia (BA) to autopsy controls from the pancreaticobiliary region of non-septic infants > 3 months old at death. All 27 control LN lacked GC a sign in infants of a primary response to antigenic stimulation. GC were found in 53% of 106 LN in 56 of 84 subjects. Presence of GC and number of GC/LN was unrelated to age at onset of jaundice but was related to older age at HPE. Absent GC in visible and incidentally removed CDLN predicted survival with the native liver at 2 and 3 years after HPE, p=0.03, but significance was lost at longer intervals. Visible surgically excised LN contiguous with the most proximal biliary remnants had one or more well-formed reactive GC in only 26/51 subjects. No correlation existed between GC in hilar LN and frank inflammatory activity in the proximal hepatic duct, or between the latter and outcome after HPE. GC in hilar LN correlated with generalized neutrophilic pericholangitis in 80 contemporaneous liver biopsies (p=0.04) but not with overall intensity of portal cellular infiltrates. The absence of consistent evidence of antigenic stimulation in LN contiguous with the biliary remnant argues for a limited role for infection in the etiology of biliary atresia. The intense inflammatory lesions occasionally found in remnants and the acute pericholangitis found in a minority of liver biopsies could be secondary either to bile-induced injury or secondary infection established as obstruction evolves.