Endocrine Abstracts

Background: Haematological side effects of Carbimazole including aplastic anaemia, thrombocytopenia and agranulocytosis are widely reported, but haemolytic anaemia is a rare occurrence. In such situations, the management options available for treating overactive thyroid disease will be limited, especially in frail elderly individuals. We report a case of Carbimazole induced haemolytic anaemia successfully treated with steroids and omitting the medication.

Case Presentation: An 83 year old female presented with tiredness, low mood, indigestion, palpitations and anxiety. She was mildy thyrotoxic with no clinically evident goitre. Her TSH was suppressed at <0.02mU/l with high fT4 (32.9 pmol/l). The thyroid receptor antibody (TRAb) was negative and Thyroid uptake scan revealed a total thyroid uptake of 0.7% (normal 0.3-3%). Both lobes of the thyroid appeared relatively large and had heterogeneous uptake without a discrete avid nodule. The diagnosis of hyperthyroidism was made and she was started on carbimazole 10 mg once daily. Three weeks later on therapy, she presented with yellowish discoloration of her body and worsening tiredness. She was found to be anaemic with haemogloblin of 63g/l, high retic count of 412 x 109/l, polychromasia and spherocytes confirming haemolytic anaemia. She had positive auto anti-e, pan reactive indirect antiglobulin test (IAT) and the diagnosis of Carbimazole induced haemolytic anaemia was made. She was transfused with 3 units of packed red cells. Carbimazole was discontinued and she was started on high dose steroids with gradual tapering for which she responded well. She remained euthyroid and no further anti-thyroid medications were required.

Conclusions: Carbimazole induced haemolytica anemia is an extremely rare adverse effect of the medication. The awareness and timely management can prevent the patients from having disastrous complications and outcomes.