Review article: the aetiology of primary Budd-Chiari syndrome - differences between the West and China

BACKGROUND

China may have the largest number of Budd-Chiari syndrome (BCS) cases in the world (at least 1914 original papers were published, and at least 20 191 BCS patients were reported). Considering the discrepancy in the clinical profiles and preferred treatment selection of primary BCS between the West and China, understanding its aetiology in these two different regions is very important.

AIM

To review the data from large cohort studies and meta-analyses to illustrate the epidemiology of risk factors for BCS in the West and China.

METHODS

Relevant papers were identified by major English- and Chinese-language databases, conference abstracts, and by manual search.

RESULTS

Risk factors reviewed include myeloproliferative neoplasms (MPNs) and their related gene mutations, anti-phospholipid syndrome, paroxysmal nocturnal haemoglobinuria (PNH), hyperhomocysteinaemia and 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T mutation, factor V Leiden (FVL) and prothrombin G20210A mutations, inherited anti-thrombin, protein C and protein S deficiencies, pregnancy and puerperium, poverty, and family history.

CONCLUSIONS

We examined the differences in the aetiological distribution of BCS between the West and China. Several recommendations should be considered in Chinese BCS patients: (i) screening for hyperhomocysteinaemia and MTHFR mutation should be regularly performed; (ii) screening for MPNs, PNH, and anti-phospholipid syndrome should be selectively performed; (iii) inherited anti-thrombin, protein C, and protein S deficiencies should be actively explored; (iv) screening for FVL and prothrombin G20210A mutations may be unnecessary; and (v) the clinical significance of pregnancy and puerperium, poverty with bacterial infections and unsanitary environments, and family history as possible risk factors should never be neglected.

Increased prevalence of heparin-induced thrombocytopenia in patients with Budd-Chiari syndrome: a retrospective analysis

BACKGROUND

Budd-Chiari syndrome (BCS) is a rare, potentially fatal disease characterized by hepatic venous outflow tract obstruction. Heparin-induced thrombocytopenia (HIT) is an immune-mediated complication of heparin therapy, with mortality approaching 10%. The reported prevalence of HIT in adults is 0.2-5.2%. Expert consensus through case reports is the only existing evidence of HIT in BCS. To our knowledge, this is the first study to formalize this anecdotal evidence.

METHODS

A retrospective analysis was carried out of patients presenting at a tertiary liver centre with acute liver failure because of BCS or BCS as the primary indication for liver transplantation between 2000 and 2013. The prevalence of HIT in the study group was compared with the highest reported prevalence in adult medical patients receiving heparin (5.2%). Mortality, length of stay and liver transplantation rates were also studied.

RESULTS

Of 32 BCS patients, 9 (28.1%) developed HIT, significantly higher than the previously reported prevalence of HIT in medical patients (5.2%) (P<0.0001). There was no difference in mortality (P=0.66), length of stay (P=0.58) and liver transplantation rate (P=0.39) between HIT-positive and HIT-negative patients.

CONCLUSION

The prevalence of HIT (28.1%) in our cohort of BCS patients is significantly higher than that in the general population (0.2-5.2%). Although this study was not powered to detect outcome differences, as heparin is the mainstay of acute BCS treatment, this represents a significant risk. We recommend a high index of suspicion for HIT in patients with BCS and thrombocytopenia, an appropriate HIT-testing strategy and consideration of direct thrombin inhibitors.