Porto-sinusoidal vascular disease-like alterations in transplant liver biopsies: A clinicopathologic observation of transplant-associated portal vasculopathy.

OBJECTIVE

Non-cirrhotic portal hypertension (NCPH) encompasses hepatic vascular disorders without cirrhosis, now grouped under porto-sinusoidal vascular disease (PSVD). While PSVD features are well described in native livers, their significance in the liver transplant setting remains unclear and may present diagnostic challenges. This study aimed to investigate PSVD-like histologic alterations in liver allografts and their clinical relevance.

DESIGN

We retrospectively analyzed 95 liver biopsies from 43 transplant recipients (2020-2022). Biopsies were reviewed for PSVD-specific features (obliterative portal venopathy [OPV], nodular regenerative hyperplasia [NRH], incomplete septal fibrosis) and nonspecific features (portal tract abnormalities, architectural disturbance, mild perisinusoidal fibrosis, non-zonal sinusoidal dilatation). Clinical data, including liver function tests (LFTs) and rejection status, were recorded.

RESULTS

Among 95 biopsies, 37% showed OPV, 33% NRH, and 16% incomplete septal fibrosis. Nonspecific findings were frequent with portal tract abnormalities in 99%, sinusoidal dilatation in 68%, and architectural disturbance in 67%. PSVD alterations appeared more common at longer post-transplant intervals but showed no significant association with acute cellular rejection or abnormal LFTs.

CONCLUSIONS

PSVD-like histologic alterations are common in post-transplant biopsies which do not correlate with acute cellular rejection or liver function abnormalities. These findings suggest the presence of PSVD-like alterations is likely multifactorial and may be better characterized as transplant-associated poral vasculopathy rather than true PSVD. Recognizing these changes in the transplant setting is essential to avoid misinterpretation and ensure accurate diagnosis. An evidence-based terminology and well-defined criteria for the diagnosis of PSVD are needed.