Haem-Onc Flashcards
Features of ALL?
Peak incidence 2-5 years of age and boys affected slightly more commonly.
Proliferation of lymphoid lineage - not enough space in bone marrow for myeloid lineage.
Anaemia - lethargy and pallor
Neutropenia - severe infections
Thrombocytopenia - easy bruising and petechiae
Bone pain - secondary to bone marrow infiltration Splenomegaly Hepatomegaly Fever present in up to 50% of new cases Testicular swelling.
What are the types of ALL?
Common ALL (75%) - CD10 present, pre-B phenotype
T-cell ALL (20%)
B-cell ALL (5%)
Investigations for ALL?
FBC - anaemia, neutropenia, thrombocytopenia
Blood film - circulating blast cells (immature cells)
Bone marrow infiltrated with blast cells (>20%)
Poor prognostic factors for ALL?
Age <2 and >10 WBC >20 at diagnosis T or B cell surface markers Non-caucasian Male sex
Main causes of Iron deficiency anaemia?
Excessive blood loss - menorrhagia, GI bleeding.
Inadequate dietary intake - vegans.
Poor intestinal absorption - coeliac disease, atrophic gastritis
Increased iron requirements - during rapid growth, pregnancy women.
Features of iron deficiency anaemia?
Fatigue SoB on exertion Palpitations Pallor Nail changes - koilonychia Hair loss Atrophic glossitis Post-cricoid webs Angular stomatitis.
Investigations for iron deficiency anaemia?
History
FBC - hypo chromic microcytic anaemia
Serum ferritin - usually low but can’t rule out if high.
TIBC - high - reflects low iron stores.
Blood films - anisopoikilocytosis, target cells, pencil poikilocytes
Endoscopy - rule out malignancy
Low reticulocyte count - unable to form RBCs because of low iron
Treatment of iron deficiency anaemia?
Manage underlying cause
Increase iron in diet - meat, beans, lentils, fish, leafy green veg, porridge
Oral supplements (ferrous sulphate 200mg TDS) - take for 3 months after def. has been corrected to replenish stores.
Side effects of tablets - nausea, abdominal pain, constipation, diarrhoea.
Don’t take with tea/milk/coffee as this reduces iron absorption.
What is Immune thrombocytopenia? Features? Management?
Immune-mediated reduction in platelet count.
Autoantibodies directed against glycoprotein IIb/IIIa or Ib-V-IX complex.
Typically more acute in children than adults.
M = F
May follow infection or vaccination.
Self limiting course over 1-2 weeks.
What is neuroblastoma?
Malignancy of neural crest cells that normally give rise to paraspinal sympathetic ganglia and adrenal medulla.
Second most common solid tumour in childhood.
Features of neuroblastoma?
Depends on location.
Abdominal mass or mediastinal mass - can cause respiratory distress
Sympathetic signs - tachycardia cardia, tachypnoea etc
Hepatomegaly, LN enlargement
Opsoclonus-myoclonus (dancing eye syndrome)
Diarrhoea (secretion of vasoactive peptide)
Diagnosis of neuroblastoma?
Biopsy
Raised urinary catecholamines
PET-CT
Bone marrow aspirates and trephine.
Management of neuroblastoma?
Surgical resection, chemotherapy or radiotherapy.
What is nephroblastoma/Wilm’s tumour?
Malignancy of embryonal cells of metanephros - cell proliferation without normal tubular and glomerular differentiation.
Features of nephroblastoma/Wilm’s tumour?
Children <5, median age of 3.
Abdominal mass Painless haematuria Flank pain Hypertension Anorexia, fever Unilateral in 95% of cases Metastases in 20% of patients - lung.
Associations of Nephroblastoma/Wilm’s tumour?
Beckwith-Wiedemann syndrome
Part of WAGR syndrome - Wilm’s, aniridia, genitourinary malformations, mental retardation.
Investigations of nephroblastoma/Wilm’s tumour?
CT - intrinsic renal mass with mixed solid and cystic densities
Biopsy
Management of nephroblastoma/Wilm’s tumour?
Nephrectomy
Chemotherapy
Radiotherapy if advanced disease
Prognosis - good, 80% cure rate.
What is Ewings sarcoma? Features and management?
Tumour of bones
Swelling and pain at site of tumour, fever, bone fracture.
Common in legs, pelvis and chest wall.
Often get haem symptoms due to bone marrow involvement.
Treatment - Chemotherapy, radiotherapy, surgery, BMT
What is sickle cell anaemia?
Autosomal recessive - synthesis of abnormal haemoglobin chain (HbS).
Screened in neonatal blood spot screening (heel-prick test) at 5-9 days of life.
More common in Africans - protection against malaria.
Symptoms don’t tend to develop until 4-6 months when abnormal HbSS molecules take over from foetal Hb.
Blood film may show target cells.
Pathophysiology of sickle cell anaemia?
Glutamate to valine in two beta chains.
Causes decreased water solubility of deoxy-Hb -> in deoxy states, HbS polymerises and cases RBCs to sickle.
Sickle cells are fragile and haemolyse -> block small blood vessels causing infarction.
Types and features of sickle cell crisis?
Acute chest syndrome - dyspnea, chest pain, pulmonary infiltrates, low pO2. Most common cause of death after childhood.
Thrombotic (painful crisis) - precipitated by infection, dehydration, deoxygenation. Multiple organ infarction.
Often hand-foot syndrome in children.
Sequestration - sickling with spleen or lungs, causing pooling of blood with worsening anaemia.
Aplastic - infection with parvovirus. Sudden fall in Hb.
Haemolytic - rare. All in Hb due to increased haemolysis.
Treatment of sickle cell crisis?
Pain relief Oxygen Fluid - hydration prevents sickling Warmth Abx if infection Blood transfusion Exchange transfusion - eg if neurological complications.
What is beta-thalassaemia trait? Features?
Autosomal recessive, reduced productive of beta chains.
Mild hypochromic, microcytic anaemia.
Usually asymptomatic
HbA2 raised (>3.5%).
What is beta-thalassamia major? Features? Management?
Absence of beta chains, chromosome 11
Presents in first year of life with failure to thrive and hepatosplenomegaly
Microcytic anaemia
Raised HbA2 (2 alpha and 2 delta) and HbF raised.
Absent HbA (2 alpha and 2 beta).
Manage with repeated transfusion - risk of iron overload.
SC infusion of desferrioxamine.
What is alpha-thalassaemia? Features?
Deficiency of alpha chain in Hb.
2 separate alpha-globulin genes are located on each chromosome 16.
Clinical severity depends on number of alpha chains present.
If 1 or 2 alpha chains absent - blood picture would be hypo chromic and microcytic, but Hb levels would be normal.
Loss of 3 alpha chains - hypochromic microcytic anaemia with splenomegaly. Known as Hb H disease.
If all 4 alpha chains absent - death in utero (hydrops fetalis, Bart’s hydrops).
What is haemophilia? Features? Blood tests? Management?
X-linked recessive disorder of coagulation.
Up to 30% of patients have no family history of condition.
Haemophilia A - def. in factor 8
Haemophilia B - def. in factor 9
Haemarthroses, haematomas
Prolonged bleeding after surgery or trauma.
Prolonged APTT
Bleeding time, thrombin time, prothrombin time normal.
Factor 8 and 9 injections.
What is the pathophysiology of haemolytic anaemia?
Intravascular haemolysis, free Hb is released which blinds to haptoglobulin.
As haptoglobulin becomes saturated, haemoglobin binds to albumin forming methaemalbumin (detected by Schumm’s test).
Free Hb excreted in urine as haemoglobinuria, haemosiderinuria.
Intravascular causes of haemolytic anaemia?
Mismatched blood transfusion G6PD Red cell fragmentation - heart valves, TTP, DIC, HUS Paroxysmal nocturnal haemoglobinuria Cold autoimmune haemolytic anaemia.
Extravascular causes of haemolytic anaemia?
Haemoglobinopathies - sickle cell, thalassaemia
Hereditary spherocytosis/eliptocytosis
Haemolytic disease of newborn
Warm autoimmune haemolytic anaemia.
Drug causes of haemolytic anaemia?
Methyldopa
Penicillin
Dapsone
