Secondary thrombotic microangiopathy with severely reduced ADAMTS13 activity in a patient with Capnocytophaga canimorsus sepsis: a case report

• Published in: Transfusion Vol. 58; no. 10; pp. 2426 - 2429
• Main Authors: Smeets, Nori J L, Fijnheer, Rob, Sebastian, Silvie, De Mast, Quirijn
• Format: Report
• Language: English
• Published: 01-10-2018
• ISSN: 1537-2995
• DOI: 10.1111/trf.14829

BACKGROUNDThe Gram-negative bacillus Capnocytophaga canimorsus may cause a severe illness resembling thrombotic thrombocytopenic purpura (TTP). The pathogenesis and optimal therapy of this secondary thrombotic microangiopathy (TMA) remain uncertain.CASE REPORTA 63-year-old Caucasian man was admitted with suspicion for TTP, but blood cultures grew C. canimorsus. Initial investigations revealed severe thrombocytopenia, a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) activity level of less than 1%, and strongly elevated D-dimer and lactate dehydrogenase levels. He made a full recovery with antibiotics and plasma infusion for 3 days. Plasmapheresis was not performed. Retrospective determination of serial ADAMTS13 activity levels revealed that ADAMTS13 activity had already increased to 25% at the start of plasma infusion.CONCLUSIONThis case highlights that a C. canimorsus sepsis may cause a secondary TMA with a severe ADAMTS13 deficiency. It also illustrates that the adjunctive role of plasma exchange or plasma infusion is doubtful as ADAMTS13 activity levels increased with antibiotics alone.