Acute lymphoblastic leukemia Flashcards
What is Acute Lymphoblastic Leukaemia (ALL)?
ALL is the most common malignancy in children, accounting for 80% of childhood leukaemias, with peak incidence at 2-5 years.
How does gender affect the incidence of ALL?
Boys are affected slightly more commonly than girls in cases of ALL.
What are the hematological features of ALL due to bone marrow failure?
Features include anaemia (lethargy, pallor), neutropaenia (frequent/severe infections), and thrombocytopenia (easy bruising, petechiae).
What are some non-hematological features of ALL?
Non-hematological features include bone pain, splenomegaly, hepatomegaly, and testicular swelling.
What is the frequency of fever in new cases of ALL?
Fever is present in up to 50% of new cases of ALL, indicating possible infection or constitutional symptoms.
What are the primary types of ALL?
The types of ALL include common ALL (75%, pre-B phenotype, CD10 positive), T-cell ALL (20%), and B-cell ALL (5%).
What factors are considered poor prognostic indicators in ALL?
Poor prognostic factors include age under 2 or over 10 years, WBC count over 20 * 109/l at diagnosis, T or B cell surface markers, non-Caucasian ethnicity, and male sex.
A three-year-old girl presents with her parents to the accident and emergency department. The parents are concerned that they’ve noticed a new widespread rash on her abdomen. The parents deny any history of trauma or recent infection.
On examination you note a petechial rash covering the anterior abdomen and to a lesser extent the posterior right forearm. The child looks pale and is not playing with the toys set out. You also find hepatosplenomegaly and cervical lymphadenopathy.
While waiting for blood results you dip her urine which proves unremarkable and take a tympanic temperature reading of 36.6º.
What is the most likely diagnosis?
Non-accidental injury
Meningococcal septicemia
Acute lymphoblastic leukaemia
Henoch-Schonlein purpura
Haemophilia A
Acute lymphoblastic leukaemia may present with haemorrhagic or thrombotic complications due to DIC.
Trauma, accidental or not, can result in a petechial rash. However, with the other salient findings in this child another diagnosis is more likely.
Meningococcal disease is what comes to everyone’s mind with a non-blanching rash and is likely why the parents brought their child to the emergency department in the first place. What counts against this option is no obvious source of infection and the fact the girl is apyrexial.
The lesions of Henoch-Schonlein purpura are normally confined to buttocks, extensor surfaces of legs and arms. Other symptoms such as haematuria or swollen painful knees and ankles are not present.
Haemophilia A is a genetic deficiency of clotting factor VIII, that usually affects males. Due to the other findings on examination, it is not the most likely diagnosis.
A 4-year-old male presents to the emergency department after his mother brings him in, concerned about his increasing lethargy over the past few days. He has a temperature of 38.6ºC, and his mother says he is looking more pale than usual. Physical examination reveals petechiae and bruising of the lower extremities.
Blood results are as follows:
Hb 94 g/L (135-180)
Platelets 86 * 109/L (150 - 400)
WBC 26 * 109/L (4.0 - 11.0)
Neutrophils 1.0 * 109/L (2.0 - 7.0)
What is the most likely diagnosis?
Acute lymphoblastic leukaemia
Aplastic anaemia
Beta thalassaemia
Idiopathic thrombocytopenic purpura
Bacterial meningitis
Acute lymphoblastic leukaemia
ALL is the most common childhood leukaemia and presents with anaemia, neutropaenia and thrombocytopaenia
ALL is the most common form of childhood cancer and characteristically presents with pallor, lethargy, splenomegaly, and petechiae. In addition, laboratory testing typically reveals anaemia, neutropaenia, leukocytosis, and thrombocytopaenia, as seen in this patient.
Aplastic anaemia is characterised by pancytopenia and hypoplastic bone marrow. While this condition can cause fatigue, pallor, thrombocytopaenia and neutropaenia, the presence of leukocytosis rules out aplastic anaemia as there would be leukopenia (low white blood cells) instead.
Thalassaemia is a group of genetic conditions whereby incorrect production of haemoglobin results in anaemia. Beta thalassaemia is a defect specifically in beta-globin chain production and can present with fatigue, hepatomegaly, splenomegaly, and jaundice. It commonly features target/teardrop cells on blood film. However, this does not match with the patient’s blood film nor his clinical presentation.
Idiopathic thrombocytopenic purpura (ITP) is an immune-mediated reduction in platelet count. ITP would explain the fatigue, pallor, and petechiae/bruising of the patient but would not explain the leukocytosis and neutropaenia seen in the patient. It is also common for ITP to eventuate following a recent viral illness.
Meningitis is a cause of fever and purpura, as seen in this patient. However, you would expect to see neutrophilia in bacterial meningitis, not neutropaenia; therefore, bacterial meningitis is unlikely here.
