title: Infiltrative (sinusoidal) and hepatitic patterns of injury in acute cellular rejection in liver allograft with clinical implications.
abstract: Acute cellular rejection post liver transplant occurs most commonly but not exclusively in the first year. In this study, we report two patterns: sinusoidal infiltrative and hepatitic, which are not considered in the Banff system. We describe their presentation, response to Solu-Medrol, and compare these to the typical moderate-severe acute cellular rejection. Patients transplanted from 2007 to 2012 at University Health Network, who had biopsy-proven rejection in the first year, were studied. Baseline transaminases and bilirubin, time of acute cellular rejection, follow-up, and treatment responses were analyzed. A total of 407 biopsies were received, of which 77 had diagnosis of acute cellular rejection with rejection activity index 5 or above; 49 from viral hepatitis patients were excluded. Twenty-eight were included; 15/28 (54%) had typical acute cellular rejection (tACR) using Banff criteria. Six (21%) had hepatitic acute cellular rejection overlapping with typical features of acute cellular rejection; seven (25%) had infiltrative acute cellular rejection (iACR) overlapping with typical features. The iACR occurred later than the tACR (124 versus 50 days; P = 0.032) and had a higher rise in baseline aspartate aminotransferase (ΔAST) compared with tACR (289 U/l versus 109 U/l; P=0.046). Only one out of seven patients with iACR (14 versus 40% in tACR) failed Solu-Medrol boluses and required thymoglobulin. Patients with hepatitic acute cellular rejection (hACR) had similar ΔAST (P = 0.12) but higher bilirubinemia than typical acute cellular rejection (tACR) (160 μmol/l versus 35 mol/l; P = 0.039) and required thymoglobulin in four out of six (67% versus 40%) instances. Patients with iACR had higher ΔAST than tACR but better Solu-Medrol response compared with both tACR and hACR. hACR is different from plasma cell-rich late-occurring cellular rejection in its pattern but similar in its poor Solu-Medrol response.
authors.affiliation: Laboratory Medicine, University of Toronto, Toronto, ON, Canada.
authors.forename: Iram
authors.initials: I
authors.lastname: Siddiqui
authors.affiliation: Multiorgan Transplant Programs, University Health Network, University of Toronto, Toronto, ON, Canada.
authors.forename: Nazia
authors.initials: N
authors.lastname: Selzner
authors.affiliation: Laboratory Medicine, University of Toronto, Toronto, ON, Canada.
authors.forename: Sara
authors.initials: S
authors.lastname: Hafezi-Bakhtiari
authors.affiliation: Multiorgan Transplant Programs, University Health Network, University of Toronto, Toronto, ON, Canada.
authors.forename: Max A
authors.initials: MA
authors.lastname: Marquez
authors.affiliation: Laboratory Medicine, University of Toronto, Toronto, ON, Canada.|Multiorgan Transplant Programs, University Health Network, University of Toronto, Toronto, ON, Canada.
authors.forename: Oyedele A
authors.initials: OA
authors.lastname: Adeyi
mesh_terms: D064591:Allografts; D005260:Female; D006084:Graft Rejection / Q000473:pathology*; D006801:Humans; D016031:Liver Transplantation; D008297:Male