Objective
Hepatic veno-occlusive disease (HVOD) has attracted increasing attention in recent years due to its relationship with ingestion of Gynura segetum. The mortality of severe HVOD remains high due to the lack of specific therapies. The aim of the study was to delineate the clinical characteristics and outcomes and explore the potential prognostic factors of HVOD.

Methods
This was a single-center retrospective study. Eighty-nine HVOD patients were screened from the First Affiliated Hospital of Zhejiang University with an ingestion history of G. segetum before developing symptoms from January 2009 to May 2018. The enrolled patients were divided into the survivor and death groups according to the clinical follow-up that ended on September 1, 2019. The demographic variables and clinical data of the patients were recorded. A binary logistic regression analysis and receiver operating characteristic curve were conducted to identify the prognostic factors and assess the prognostic value for predicting death, and a survival analysis was performed to evaluate the clinical outcomes.

Results
Sixty-four patients were eligible for further analysis. Most patients showed abdominal distension and were positive for migrating dullness in the abdomen (P = 0.740 and P = 0.732, respectively). The patients who died had higher levels of model for end-stage liver disease score, and higher prothrombin time than those who survived (both P < 0.001). All HVOD patients in both the survival and death groups showed ascites with abnormal imaging presentations of the liver parenchyma and hepatic blood vessels. Unexpectedly, we found that hydrothorax was detected in 21 (65.63%) patients in the death group and 19 (59.38%) patients in the survivor group during hospitalization, which was rarely mentioned in previous studies. Furthermore, international normalized ratio (INR) and creatinine are found to be potential independent prognostic factors for predicting death. Six severe patients achieved clinical improvements and survived after liver transplantation.

Conclusion
HVOD can be induced by the ingestion of G. segetum, and INR combined with creatinine has prognostic value for predicting death. Liver transplantation may be an effective treatment option for severe HVOD patients.

Key words: Hepatic veno-occlusive disease, Gynura segetum, Clinical characteristics, Prognostic, Survival analysis