A Rare Case of Severe Haemolytic Anaemia Due to Folic Acid Deficiency in a Patient with Beta Thalassaemia Trait

Severe haemolytic anaemia is a rare and often overlooked presentation of folic acid deficiency. Here we describe a case of severe haemolytic anaemia secondary to folic acid deficiency in a patient with beta thalassaemia trait. A 20-year-old young woman of Pakistani origin, previously independent and active with no significant past medical history, presented with vertigo, dizziness, tiredness, and muscle stiffness. On admission, she had a haemoglobin level of 23 grams/L, folic acid level <1.3 micrograms/L with evidence of haemolysis. Her peripheral blood film was consistent with severe haematinic deficiency. Following diagnosis of severe normocytic anaemia and non-immune extravascular haemolysis secondary to folate deficiency, she received blood transfusions and high-dose oral folic acid for three months. On follow-up, haemoglobin level had improved to 104 grams/L, folate levels were replenished, and she had resumed her normal life. She was incidentally found to have beta thalassaemia trait which explained the persistent mild anaemia. Hence, folic acid deficiency when significant may lead to severe haemolytic anaemia but shows excellent haematological response to treatment with high dose oral folic acid.