Thank you for your interest in our article. Your response does highlight a number of important issues. First, there is growing evidence that the prevalence of occult PVT is many-fold greater than that of clinically evident disease. Improvements in diagnostic imaging will likely continue to augment this discrepancy. Although it seems prudent that patients with occult PVT receive anticoagulants, it is unknown if anticoagulation improves patient outcomes. On the other hand, symptomatic patients obviously need to be investigated and treated promptly.
Although our study suggests that the rate of PVT after laparoscopic splenectomy is at least as high as after open splenectomy, Ikeda and associates1 found in a recent study that the incidence of thrombosis after laparoscopic splenectomy was 55% — significantly higher than after open splenectomy. Although further research is needed, it remains possible that unique features of laparoscopic splenectomy (pneumoperitoneum, positioning, use of staplers) do modify the risk of thrombosis. But how operative factors contribute to the risk of thrombosis remains unknown.
Lastly, it is important to acknowledge that even if all patients are screened for PVT using the same imaging techniques and protocol, it seems evident that the rate of PVT will vary among series. It is well established that hematologic malignant conditions do carry an elevated risk of thrombosis. Hence, the composition of each series will influence the observed frequency of thrombosis. It is also likely that benign disease such as ITP, sickle cell disease and thalassemia each have unique risk profiles. Furthermore, it is always worth considering whether additional comorbidities specific to a patient population being served (i.e., protein C and S deficiencies, synchronous malignant conditions) are influencing observed outcomes.
Footnotes
Competing interests: None declared.