Haematology Flashcards
James is a four-year-old boy who has known severe haemophilia A. He presents to ED with sudden onset drowsiness and left sided weakness. His vital signs are within normal limits and he is maintaining his own airway.
What is the most important next step in his management?
CNS bleeds are an important cause of morbidity and mortality in patients with haemophilia, and increase in incidence with increasing severity of haemophilia.
Treatment dose factor VIII bolus. Suspected CNS bleeds should be treated prior to radiological confirmation.
Emicizumab is a monoclonal antibody that binds factor IXa and X simultaneously, substituting for the role of factor VIIIa in activating factor X. It is effective as prophylaxis in patients with haemophilia A with and without inhibitors via weekly-monthly subcutaneous injections. It is not effective as treatment in acute bleeding.
Factor IX is deficient in haemophilia B.
small cephalohaematoma NVD, D6 poor feeding and non-bile vomiting. In ED hypotonic, apnoea and pale. Normal INR and fibrinogen - prolonged APTT, anaemia Hb 65. Platelets normal, Cr US NAD.
Haemophilia A
APTT measures the intrinsic and common pathways. Involves factors I, II, V, VIII, IX, X, XI, & XII. Of note, doesn’t measure factor VII.
Extrinsic pathway = measured by INR (prothrombin time); greatly affected by Factor VII, whose synthesis requires Vitamin K.
Therefore likely to be a problem with the intrinsic pathway. Would be consistent with a factor deficiency.
What is the best test to determine a child’s response to oral iron supplementation for iron deficiency anaemia?
Reticulocyte count at day 7 is the best test to determine a child’s response to oral iron supplementation for iron deficiency anemia. A rise in reticulocyte count indicates that the bone marrow is responding to the iron therapy and producing new red blood cells. This response can be seen within 5-7 days of starting iron therapy.
