Rationale: Heparin-induced thrombocytopenia (HIT) is a common antibody-mediated adverse reaction that occurs after heparin exposure. However, few case reports exist regarding nonantibody-mediated HIT.
Patient concerns and diagnoses: An 81-year-old female diagnosed with rapidly progressive glomerulonephritis (RPGN) presented with atypical presentation of non antibody-meditated HIT after using heparin during hemodialysis.
Interventions and outcomes: Patient was initiated on hemodialysis and presented with thrombocytopenia following administration of heparin during dialysis. After ruling out all other causes of thrombocytopenia, HIT was suspected to be the cause. Patient's 4Ts score was 6 points, and Naranjo adverse drug reaction probability scale was a score of 10. However, enzyme-linked immunoassay for platelet factor 4 (PF4)/heparin antibodies was negative, indicating non-antibody mediated HIT. Patient eventually continued hemodialysis without heparin.
Lessons: This patient case presented a rare presentation of HIT type I reaction due to heparin and demonstrated the importance of timely recognition of thrombocytopenia, appropriate diagnosis and management, and possible existence of a new atypical or subtype of HIT reaction.