Sinusoidal Portal Hypertension in Non-Cirrhotic Patients: Description of a Post-Transplant Cohort with Conflicting Clinical/Radiologic Features and Highlight of Deficiencies in the Current Fibrosis Staging Systems
Hector Li-Chang, Sara Hafezi-Bakhtiari, Oyedele A Adeyi. University Health Network, University of Toronto, Toronto, ON, Canada
Background: Cirrhosis produces sinusoidal portal hypertension (sPHTN) and often correlates with high corrected sinusoidal pressures (CSP). Current pathology staging recognizes cirrhosis as regenerating nodules, fibrous septae, and loss of normal micro-architecture. We here describe pathologic findings in a cohort of 30 post-transplant (postTX) patients in whom portal hypertension was clearly present but had no radiologic features of cirrhosis except increased CSP in some. These patients had extensive sinusoidal fibrosis but preserved underlying micro-architecture and absence of true nodules.
Design: Clinical and radiologic history of postTX patients biopsied with portal hypertension (PHTN) clinically believed to be non-cirrhotic because of absence of radiologic features are identified. These biopsies were pulled and their H&E, trichrome, and reticulin stains reviewed.
Results: Thirty patients between 2001 and July 2012 meet selection criteria once we excluded those with other clear morphologic explanations for portal hypertension such as NRH; outflow obstruction, and others. Time from TX to biopsy was 3.6 – 156 months (mean =54.6; median = 33.6). Of these 30 (24 male; 6 female), ascites was present in 15 (50.0%). CSP was elevated (higher than 8) in 7 of 7 who had this information. Imaging revealed “abnormal blood flow” in 3 cases; all 30 had normal synthetic function (INR <1.3). Indication for transplantation in the patients was HCV (20 or 67%) and others (autoimmune hepatitis; PBC; HBV; NASH = 10, 33%). One biopsy (3.33%) contained severe steatosis, but none had steatohepatitis. Overall 24/ 30 biopsies (80%) would ordinarily be staged as F 1-2 /4 but these as well as other 6 (F2-3) had moderate to severe sinusoidal fibrosis without nodules, real fibrous septae, or significant alteration of the hepatic micro-architecture. None of these 30 biopsies can be staged as cirrhosis by any existing criteria, yet appear to solely explain PHTN due to marked sinusoidal collagenization.
Conclusions: Diffuse, non-nodular sinusoidal fibrosis from various post-transplant injury, identified in our post-transplant cohort, have also been seen in non-transplant patients, produce the scenario for sinusoidal PHTN, but are difficult to diagnose radiologically and could potentially be under-staged by all of the current criteria. Review of existing criteria for “cirrhosis” is needed to better report non-nodular sPHTN in a uniform and easily communicated manner.
Monday, March 4, 2013 1:00 PM
Proffered Papers: Section E, Monday Afternoon