Drug-induced hepatic sinusoidal obstruction syndrome: current advances and future perspectives

Hepatic sinusoidal obstruction syndrome (HSOS) has gained recognition as a rare form of drug-induced liver injury (DILI) in recent years. Although extensively studied in the context of hematopoietic stem cell transplantation (HSCT), the applicability of this knowledge to drug-induced HSOS remains limited due to distinct etiological factors. The primary causes of drug-induced HSOS include the ingestion of pyrrolizidine alkaloid (PA)-containing plants, as well as the use of chemotherapeutic agents and immunosuppressive drugs. The underlying pathogenesis is not yet fully understood. Noninvasive diagnostic imaging modalities such as ultrasonography, computed tomography, and magnetic resonance imaging play a valuable role in diagnosis. Further research is essential to develop standardized severity grading systems and optimize treatment strategies. This review summarizes the key etiologies, pathological mechanisms, clinical features, diagnostic approaches, severity assessment, and therapeutic options for drug-induced HSOS.