20 | Atypical presentation of anaemia in an older woman on direct oral anticoagulants: the importance of differential diagnosis

D. Coppola¹, I. Gullo², D. Busni¹, G. Benati¹ | ¹AUSL Romagna, Forlì; ²Università di Bologna, Forlì.

Introduction. Anaemia in older adults on direct oral anticoagulants is attributed to occult bleeding; however, such diagnostic anchoring may impede the timely recognition of rarer aetiologies.

Objectives. To report a case of severe haemolytic anaemia masquerading as gastrointestinal bleeding, underscoring the importance of differential diagnosis in older adults.

Materials and Methods. An 88-year-old female on anticoagulants for atrial fibrillation presented with severe anaemia (haemoglobin 7.0 g/dL). In the context of suspected haemorrhage, such drugs were discontinued, and four red blood cell units were transfused. Subsequently, new-onset jaundice and laboratory findings (markedly elevated indirect bilirubin and lactate dehydrogenase, undetectable haptoglobin, and hyperferritinaemia) revealed overt haemolysis. Computed tomography and endoscopy excluded neoplasms or active bleeding. Reassessment confirmed haemolytic anaemia with a negative direct antiglobulin test (Coombs) and a minimal monoclonal immunoglobulin M (IgM) kappa component. Infectious/autoimmune screenings and targeted quantification of cold agglutinin titres were performed.

Results. Tests for Epstein-Barr virus, Cytomegalovirus, and Mycoplasma pneumoniae yielded negative results. Notably, the cold agglutinin titre was markedly elevated (1:2048). Following the diagnosis of cold agglutinin disease (CAD) and primary hypothyroidism, steroid therapy (methylprednisolone) and erythropoietin were initiated. Anticoagulation was safely resumed with low-molecular-weight heparin. Haemoglobin stabilised at 9.7 g/dL with remission of haemolysis. The patient was discharged asymptomatic and strictly advised to avoid cold exposure.

Conclusions. In older anticoagulated patients with severe anaemia, the prompt evaluation of haemolysis indices and cold agglutinins (even with a negative Coombs test) is of paramount clinical importance to avoid inappropriate transfusions and ensure correct therapeutic management.