Paediatric Haematology Flashcards
During your ward round on the paediatric unit you review a 5-year-old Caucasian male who has been admitted for chemotherapy as he has recently been diagnosed with acute lymphoblastic leukaemia (ALL). His mother worriedly asks you what his chance of survival is and how you work this out.
On reviewing the patient notes, you see he is on the 95th percentile for weight and the 60th for height. His white cell count at diagnosis was 12 * 10^9/l and there were no noted T or B cell markers on his blood film.
Which feature from this case is a poor prognostic factor?
A. Caucasian
B. Male sex
C. Presentation under the age of 5
D. White cell count over 11 * 10^9/l at diagnosis
E. Obesity
B. Male sex
It is male sex that is the poor prognostic factor here. Being Caucasian is not a poor prognostic factor.
Other poor prognostic factors are: presenting <2 years or >10 years; having B or T cell surface markers; and having a WCC > 20 * 10^9/l at diagnosis.
what are some poor prognostic factors of ALL?
- age < 2 years or > 10 years
- WBC > 20 * 109/l at diagnosis
- T or B cell surface markers
- non-Caucasian
- male sex
what is the triad of symptoms for ALL?
- anaemia: lethargy and pallor
- neutropaenia: frequent or severe infections
- thrombocytopenia: easy bruising, petechiae
when should dexamethasone should be considered in meningitis?
- frankly purulent CSF
- CSF white blood cell count greater than 1000/microlitre
- raised CSF white blood cell count with protein concentration greater than 1 g/litre
- bacteria on Gram stain
A 2-year-old boy with several small bruise-like lesions is brought to the emergency department by his mother. She reports first noticing these lesions on her son’s abdomen when bathing him two days ago, despite no obvious preceding trauma. The bruising does not appear to be spreading.
Notably, the child had mild coryzal symptoms one week ago, though has now recovered.
On examination, the child appears well in himself and is smiling. There are 4 small petechiae on the patient’s abdomen. The examination is otherwise unremarkable.
Given the likely diagnosis, what would be an indication for bone marrow biopsy?
A. Epistaxis
B. Folate deficiency
C. Photophobia
D. Splenomegaly
E. Thrombocytopenia
D. Splenomegaly
Children with immune thrombocytopenia (ITP): bone marrow examination is only required if there are atypical features
The correct answer is splenomegaly. This patient’s presentation is in keeping with idiopathic thrombocytopenic purpura (ITP), characterised by a petechial rash in an otherwise well child. ITP is an autoimmune destruction of platelets that may be triggered by a preceding viral illness.
Atypical findings that may warrant bone marrow biopsy include:
1. splenomegaly
2. bone pain
3. diffuse lymphadenopathy, which may suggest an underlying myeloproliferative malignancy
4. high/low WCC
5. failure to respond to treatment
Not E. Thrombocytopenia.
Thrombocytopenia is incorrect, as this is an expected finding in patients with idiopathic thrombocytopenic purpura. Thrombocytopenia is not an atypical finding in ITP and therefore is not an indication for bone marrow biopsy.
treatment for ITP
- usually, no treatment is required
-ITP resolves in around 80% of children with 6 months, with or without treatment - advice to avoid activities that may result in trauma (e.g. team sports)
- other options may be indicated if the platelet count is very low (e.g. < 10 * 109/L) or there is significant bleeding. Options include:
A) oral/IV corticosteroid
B) IV immunoglobulins
C) platelet transfusions can be used in an emergency (e.g. active bleeding) but are only a temporary measure as they are soon destroyed by the circulating antibodies
symptoms of ITP:
-bruising
-petechial or purpuric rash
-bleeding is less common and typically presents as epistaxis or gingival bleeding
Symptoms of TTP (mnemonic):
pentad: Nasty fever ruined my tubes:
1. neuro symptoms (eg confusion)
2. fever
3. (acute) renal failure/haematuria
4. MAHA
5. thrombocytopenia
what is the pathophysiology of TTP? Associated with:
antibodies against ADAMTS13 lead to long strands of VWF which
act like cheese wire in the blood vessels, cutting up RBCs.
TTP driven by deficiency of ADAMTS13 (which normally cleave sticky VWF multimers into monomers)
-cancer, pregnancy
HUS pathophysiology
Shiga-like toxin released by E.coli 0157:H7 in the glomerular vessels (uraemia)
Pathophysiology of DIC:
excessive exposure to tissue factor (extrinsic pathway): associated with trauma, sepsis, cancer, inflammation eg pancreatitis
DIC causes mnemonic:
I’M STONeD!)’:
-Immunological (e.g. severe allergic
reactions, haemolytic transfusion reactions, pancreatitis),
-Miscellaneous (e.g. aortic
aneurysm, liver disease),
-Sepsis/snake bites
-Trauma (including serious tissue injury,
burns, extensive surgery),
-Obstetric (e.g. amniotic fluid embolism, placental
abruption)
- Neoplastic (myeloproliferative disorders as well as
solid tumours such as pancreatic cancer)
- Drugs
why is blood so watery/unable to clot in DIC?
anticoagulant factors (adjustment) > procoagulant factor loss
why does TTP cause fever?
fever in TTP is likely caused by the release of cytokines in response to the formation of blood clots throughout the body.
What are Reed-Sternberg cells?
Multinucleated lymphocytes (lymphocytes which have a bilobed nucleus with a dense eosinophilic cytoplasm, “owl’s eye appearance”)
presentation/diagnosis/management of osteosarcoma:
Presentation
1. Pain and swelling with a prolonged onset are characteristic
2. Typically occurs in the metaphyses of long bones
Diagnosis
1. The X-ray findings of new bony growth and a periosteal reaction causing a sunburnt appearance are typical of osteosarcoma
- Signs visualised on X-ray should prompt and urgent full body CT in order to assess for any metastases.
- The definitive diagnosis is confirmed using bone biopsy taking into account the clinical picture and radiological findings.
Management
1. MDT approach, which may include surgery, radiotherapy and chemotherapy
