Haematology Flashcards
What is foetal Hb?
Hb made up of 2 alpha and 2 gamma subunits- higher affinity for O2 than adult Hb (2 alpha and 2 beta).
Conversion to adult Hb begins at 32-36wks.
What is anaemia?
What are the causes of anaemia in infancy?
Low levels of Hb in the blood.
- Most common cause is physiological anaemia of infancy: Occurs in the first 6-9wks, high O2 (compared to in vitro) delivery to tissues, increasing the Hb levels. This causes a negative feedback, reduces the levels of EPO and hence RBC production- anaemia.
- Blood loss
- Twin-twin transfusion reaction
- Haemolysis due to (a) Haemolytic disease of the new-born: Rh-ve (sensitised) mother blood mixes blood with Rh+ve baby. Leads to haemolysis and jaundice. (b) Spherocytosis (c) GDP6 deficiency.
- Prematurity: (1) Baby has taken less iron overall from mum. (2) Reduced EPO. (3) RBC can’t keep up with the growth demands within the first few wks. (4) Blood tests means baby loses lots of blood.
In older children common causes are due to poor iron intake or girls starting menopause.
What are the signs and symptoms of anaemia?
Signs: Pallor Pale conjunctiva Tachycardia Raised RR Specifically: (a) Jaundice- haemolytic (b) Angular cheilitis, koilonychia, atrophic glossitis, brittle hair/nails- iron deficiency (c) Bone deformities- thalassaemia
Symptoms: Fatigue Palpitations Headache Dizziness SOB Pica- severe iron deficiency leading to craving for dirt Hair loss- iron deficiency
How is anaemia investigated?
How is it managed?
FBC with MCV Blood film Direct-Coombs test (Haemolytic disease of the new-born) Iron studies B12 and folate Reticulocyte count Bilirubin (haemolysis)
Manage the cause of the anaemia. Often iron replacement, but some babies may require transfusions (common in premature).
What are the causes of iron deficiency anaemia?
How is it investigated?
How is it managed?
Poor iron intake (common in children), poor iron absorption (Crohns or use of PPIs) OR increased iron loss i.e. heavy menstruation.
Iron studies:
(1) TIBC- Gives an indication of capacity to bind iron. Will increase in iron deficiency anaemia.
(2) Transferrin- Iron binds to this for transportation. Will increase in iron deficiency anaemia.
(3) Transferrin saturation- Amount of transferrin which ahs iron bound. Will decrease in iron deficiency anaemia.
NB iron levels will increase during inflammation, so person can be anaemic with normal iron levels if blood test at a time of infection.
(2) and (3) can be increased in liver failure (release of iron stores) and iron supplementation.
Manage the underlying cause of the deficiency, commonly poor oral intake and so get dietician involvement.
Can supplement with ferrous sulphate or ferrous fumarate. Can also give transfusion in rare cases but infants manage well without this whilst their stores are replenished.
What is Leukaemia?
What are the different types?
What are the RF?
Cancer of stem cells of the BM.
Abnormal production of a particular lineage in the BM leading to a pancytopenia.
ALL- Most common. 2-3yrs old
AML- Common. Under 2yrs
CML- rare in children
Main RF is exposure to X-Ray in-vitro i.e. abdominal X-Ray.
Also Down’s syndrome, Fanconi’s anaemia etc.
How does leukaemia present?
Unexplained fever Night sweats Weight loss Fatigue Pallor Unexplained bleeding Petechiae/bruising Recurrent infections Abdominal pain Generalise lymphadenopathy Hepatosplenomegaly
Any child with unexplained petechiae OR hepatomegaly need referral for specialist assessment. If leukaemia is suspected then need FBC within 48hrs.
How is leukaemia investigated?
How is it manged?
What are the complications of management?
FBC- anaemia, thrombocytopenia, leukopenia and high abnormal WBC
Blood film- blast cells
BM biopsy
LN biopsy
To stage: CXR, CT, LP, immunophenotyping of abnormal cells.
Management is with chemotherapy. Can also consider radiotherapy and SC transplant.
Complications of chemotherapy- Stunted growth Hair loss Secondary malignancy Infertility Infection/immunosuppression
How is sickle cell disease diagnosed?
What are the complications of sickle cell disease?
Diagnosis can be antenatally of mothers who are carriers.
Tested at 5 days of age with new-born heel prick test.
Complications: Anaemia CKD Sickle cell crisis Acute chest syndrome Pulmonary HTN Avascular necrosis of larger joints i.e. hip Infections Stroke Priapism- Painful, sustained erection
How is sickle cell anaemia managed?
Avoid dehydration, cold weather, significant life events, infection or any potential triggers of a crisis
Keep up to date with vaccinations
Prophylactic Abx (phenoxymethylpenicillin)
Give hydroxycarbamide to increase HbF, since won’t sickle so protective against crisis and acute chest syndrome.
Blood transfusions can help with severe anaemia
Bone transplant can be curative
What is a sickle cell crisis?
What are the 4 different types?
This refers to a group of crisis which can occur with sickle cell disease, including the mild to very severe.
Important to have a low threshold, admit to hospital, keep warm, hydrated, fluids, penile aspiration in priapism, simple analgesia (avoid NSAIDs in renal impairment)
(1) Vaso-occlusive episode- VERY PAINFUL
Occlusion can lead to distal ischaemia. Present with pain, fever and infection symptoms. Male can present with priapism.
(2) Aplastic crisis-
Cessation of blood cell production due to parvovirus. Manage with transfusion, will resolve spontaneously within a week.
(3) Splenic sequestration crisis- Medical emergency
Sickle cells block flow to the spleen therefore get pooling of blood in the spleen leading to anaemia and hypovolaemia- supportive management with blood transfusion and fluid resuscitation to treat anaemia and shock. Recurrent attacks can lead to infarction and infection therefore need splenectomy.
(4) Acute chest syndrome- Medical emergency
Fever/respiratory symptoms with a new CXR infiltration.
Management is supportive but also treat underlying cause.
Antivirals/Antibiotics for infection
Blood transfusion for anaemia
Incentive spirometry to encourage deep and effective breathing
Artificial ventilation i.e. NIV or intubation
What is Hodgkin’s lymphoma?
How does it present?
What are the RF?
(RECAP)
Abnormal replication of lymphocytes. Diurnal- affecting age 20s and 50s.
Presenting with: Lymphadenopathy Fever Weight loss Night sweats Itching Pallor Fatigue Painful LN on alcohol consumption
RF: HIV EBV FHx Autoimmune conditions i.e. sarcoidosis, RA
How is Hodgkin’s lymphoma investigated?
How is it managed?
(RECAP)
LN biopsy if definitive diagnosis with presence of Reed-Sternberg cells.
Also get increased LDH.
Stage with CT, MRI or PET. Use Ann-Arbor staging.
Manage:
Chemotherapy- Increase risk of leukaemia and infertility.
Radiotherapy- Increase risk of damage to tissues, secondary malignancies and hypothyroidism.
What is non-Hodgkin’s lymphoma?
How does it present?
What are the RF?
(RECAP)
Abnormal replication of lymphocytes. Encompasses all other lymphomas which are not HL.
Presents as Hodgkin's lymphoma: Painless lymphadenopathy Fever Night sweats Weight loss Itching Fatigue
RF: HIV EBV Malaria Pesticide exposure H.pylori FHx Hep B/C
How is non-Hodgkin’s lymphoma investigated?
How is it managed?
(RECAP)
Differentiate between HL and NHL with LN biopsy.
Management dependent on stage: Watchful waiting Chemotherapy Radiotherapy Rituximab Stem cell transplant
