ABSTRACT
Rituximab, an anti-CD20 monoclonal antibody, can be used to treat immune thrombotic thrombocytopenic purpura (iTTP) during acute presentation or disease relapse. Undesirable side-effects include severe hypersensitivity reactions, particularly anaphylaxis and rituximab-induced serum sickness, with a minority not maintaining a response to treatment. Alternative humanised anti-CD20 treatments, obinutuzumab and ofatumumab, have been used. A review of the UK TTP Registry showed 15 patients received these drugs over 26 treatment episodes (eight obinutuzumab and 18 ofatumumab). Indications for alternative anti-CD20 treatment were severe infusion-related reactions, acute rituximab-induced serum sickness and a short duration of disease remission. All patients achieved disease remission (ADAMTS13 [A disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13] activity ≥30 iu/dl) after a median 15 days and 92% of episodes achieved complete remission (≥60 iu/dl). Seven patients required further treatment for disease relapse with a median relapse-free survival of 17.4 months. All patients continued to respond to re-treatment with the preceding drug when relapse occurred. There were four adverse events in 26 treatment episodes (15%) - two infections and two infusion reactions. These results suggest that obinutuzumab and ofatumumab may be considered as an alternative option to rituximab in the treatment of iTTP with a comparable safety profile, absence of significant hypersensitivity reactions and sustained normalisation of ADAMTS13.
Subject(s)
Antibodies, Monoclonal, Humanized , Purpura, Thrombotic Thrombocytopenic , ADAMTS13 Protein , Antibodies, Monoclonal, Humanized/therapeutic use , Antigens, CD20 , Humans , Purpura, Thrombotic Thrombocytopenic/drug therapy , Recurrence , Rituximab/adverse effects , Serum Sickness/chemically inducedABSTRACT
COVID-19 is a prothrombotic condition that is also associated with raised troponin levels and myocardial damage. We present a case of a 54-year-old man who was admitted with respiratory failure due to COVID-19 and developed a ST-elevation myocardial infarction (STEMI) during his admission. His coronary angiogram did not show any significant coronary artery disease other than a heavily thrombosed right coronary artery. In view of heavy thrombus burden, the right coronary artery was treated with thrombus retrieval using a distal embolic protection device in addition to manual thrombectomy and direct (intracoronary) thrombolysis without the need for implantation of a coronary stent. After successful revascularisation, triple antithrombotic therapy was instituted with an oral anticoagulant in addition to dual antiplatelets. This case illustrates the association of COVID-19 with coronary artery thrombosis, which may require disparate management of a STEMI than that resulting from atherosclerotic coronary artery disease.