The post-transplant lymphoproliferative disorders (PTLDs) are a heterogeneous group of neoplasms that are one of the most serious complications of bone marrow and solid organ transplants. Because these disorders are rare, there are no randomized trials from which to derive optimal treatment. Management can be challenging and must balance the goal of PTLD eradication with the risks of graft rejection, graft-versus-host disease, further delays in immune reconstitution and life-threatening infections, among others. This paper will provide a comprehensive review of PTLD following solid organ transplant and haematopoietic stem cell transplant with a focus on management. Included is a discussion of novel agents that are being studied in clinical trials and, when combined or sequenced with conventional therapy, have the potential to improve outcomes.

Essentials Delayed‐onset heparin‐induced thrombocytopenia can lead to severe thrombocytopenia in the setting of recent major vascular surgery.Intravenous immunoglobulin (IVIG) can be used as a supplementary treatment when platelet count fails to improve with conventional treatment.When platelet counts are severely low, benefits of using IVIG can outweigh the risks of thromboembolic events. Delayed onset heparin induced thrombocytopenia (HIT), is characterized by a late nadir due to persistent platelet‐activating IgG antibodies. It typically begins or worsens 5 or more days after heparin is discontinued with complications such as thrombosis up to 3 weeks after exposure to heparin.1–3 In 50% of cases, the platelet count can decrease to very low numbers (<20 000/μL), which is not usual for typical HIT. Here we report 2 cases of post‐operative delayed onset HIT manifesting as severe thrombocytopenia that persisted despite cessation of heparin and initiation of argatroban. Key Clinical Question: Is intravenous immunoglulin beneficial in severe refractory delayed‐onset HIT?

Risk ratio = r=r 0 . r 0 = 0.28 (percentage of total Ref patients); r, probability of being in the refractory group given each category.Horibata et al.