Porto-sinusoidal vascular disorder in a pediatric patient with prolidase deficiency: A case report.

Prolidase deficiency (PD) is a rare autosomal recessive disorder affecting collagen turnover, leading to diverse clinical manifestations including dermatologic lesions, hepatosplenomegaly, and vascular anomalies. Liver involvement in PD is poorly understood, with few reported cases. We present a child with early-onset non-cirrhotic portal hypertension and PD. The patient initially presented with neonatal hemolytic anemia and hepatosplenomegaly. At age 9, recurrent epistaxis and splenomegaly led to splenectomy. Liver biopsy revealed sinusoidal dilation and parenchymal nodularity, later progressing to esophageal varices. Genetic testing identified pathogenic variants in peptidase-D gene, suggestive of PD, and biochemical testing confirmed the diagnosis. Given suspected vasculopathy, tocilizumab was initiated with clinical improvement. This case suggests a potential link between PD and porto-sinusoidal vascular disorder (PSVD), particularly nodular regenerative hyperplasia. Further research is needed to explore prolidase's role in vascular remodeling and its contribution to PSVD-related liver pathology. Early recognition may improve management and outcomes.