haematology Flashcards
causes of iron deficiency anemia? 2
- low iron intake
- malabsorption
- blood loss: e.g meckels diverticulum
presentation of iron deficiency anemia? symptom and signs
symptoms: fatigue, dizziness, cold, dyspnea, poor feeding, pica
signs: pallor, angular cheilitis, atrophic glossitis
laboratory findings suggestive of iron deficiency anemia?
FBC: low Hb and MCV (microcytic anemia)
iron studies: low free iron, low ferritin, high total iron binding capacity
blood smear: microcytic hypo chromic RBC without schistocytes
management of iron deficient anemia?
dietary advice and iron supplements (Galfer) until iron level is normal for 3 months
define hereditary spherocytosis ? describe genetics
an autosomal dominant condition caused by mutations in spectrum/ankyrin/Band-3, resulting in defective RBC membrane
clinical features
- features of anemia + jaundice (due to hemolysis)
- splenomegaly
- may present with aplastic crisis after infections with parvovirus B19 infection
Diagnosis of hereditary spherocytosis ?
- FBC: low Hb and high reticulocytes
- blood smear shows spherocytes
- confirmatory test: EMA test (Eosin-5 maliemide) - EMA usually binds cell membrane proteins and fluorescence, absence of cell surface proteins reduced fluorescence
define G6PD deficiency? genetics ? what population is it common in
X-linked recessive disorder commonly seen in patients from middle-east and Africa. G6PD enzyme protects the RBC from oxidation and hemolysis. dysfunction leads to increased oxidative stress under certain triggers leafing to hemolysis
precipitants of G6PD deficiency?
- infections (biggest precipitant)
- antibiotics (co-trimaxaole, quinolone, sulphonamide)
- analgesics: aspirin
- chemicals: naphthalene
- food: fava beans
presentation of G6PD?
acute hemolysis from exposure to precipitant which includes
- features of anemia + jaundice + dark urine
- abdomina pain, fever, malaise
how is the diagnosis of G6PD deficiency made? when should it not be done to avoid false negative?
G6PD enzyme assay. not to be performed during an acute hemolytic episode (due to high rates of false-negatives
management of G6PD deficiency?
- avoid precipitants
- treat infections
- manage acute hemolytic episodes: hydration and transfusions
management of hereditary spherocytosis ?
- supportive management: folic acid and transfusions
- if severe disease with aplastic crisis: splenectomy
define Beta-thalassemia?
a disorder of abnormal hemoglobin production
what populations is beta-thalassemia common in ?
india, middle-east, and Mediterranean
what are the 2 types of beta-thalassemia?
major: transfusion-dependent, cannot produce HbA
intermedia: produce a small amount of HbA
minor: often asymptomatic
what age does beta-thalassemia usually present? how may it present?
3-6 months
severe and transfusion dependent anemia and jaundice , faltering growth, if untreated: maxillary overgrowth and skull bossing
management of beta-thalassemia
- regular transfusions (especially for major, less regularly for intermedia) + deferoxamine (iron chelator to prevent transfusion related hemochromatosis, which can lead to cirrhosis and cardiomyopathy)
define sickle cell disease ? genetics and population most commonly seen in?
autosomal recessive disorder cause by the replacement of glutamine by valine on codon 6 of the beta global gene. occurs in 1/2000, commonly in patients of afro-carribean origins
clinical features:
anemia, jaundice, hepatosplenomegaly
presentations of sickle cell disease?
- vaso-oclusive episodes: dactylitisi (typically the first complaint at 6 months), avascular necrosis of the long bones, priapism: painful erection leading to necrosis, acute chest syndrome, splenic sequestration crisis
- long term sequale of chronic anemia: cerebral vascular accident, cardiac disease, renal disease, leg ulcers, delayed puberty
- acute hemolytic or aplastic anemia
management of sickle cell disease?
- long term penicillin prophylaxis and annual immunization with flu and PCV
- avoid precipitants of crises (dehydration, cold)
- management of acute pain crisis: analgesia, fluids and antibiotics (infection-induced), exchange transfusion for acute chest syndrome, priapism or stroke
- chronic disease: hydroxyurea to boost the child HbF production (notable side effect is white cell suppression). if this fails then consider bone marrow transplant
Define hemophilia? what are the 2 types
X-linked recessive disorder characterized by recurrent spontaneous bleeding into joints and muscles, ultimately leading to crippling arthritis. inherited coagulopathy
A= factor 8 deficiency
B= factor 9 deficiency
how may hemophilia present at birth?
scalp hematoma
how may hemophilia present in a neonate?
- bleeding post circumcision
- seizures from intracranial hemorrhage
how may hemophilia present in children?
tripping and bleeding
in haemophilic patients any spontaneous bleeding without minor trauma indicates …. disease with … % of factors present
severe
<1%
how is hemophilia diagnosed?
- coagulation screen: prolonged aPTT, normal PT, normal platelets
- factor activity levels: <5%
management of hemophilia ? prophylactic, active bleeding, mild hemophilia
- prophylactic factor therapy for patient with high risk of bleeding
- active bleeding management: transfusion of recombinant F8 for hemophilia A, or F9 for type B. if unknown, give fresh frozen plasma (prothrombin complex concentrate does not contain factor 8 – only vitamin K dependent)
- mild hemophilia A = desmopressin
what is important to remember to avoid in hemophilia patients ?
always avoid NSAIDs, aspirin and intramuscular injections
recurrent hemarthroses in patients with hemophilia may lead to haemophilic arhtropathic necessitating?
joint replacement
define Von willebrand disease?
inherited deficiency or inactivity of vWF leading to coagulopathy.
what are management options for vWF ?
- desmopressin
- vWF/factor 8 replacement
- vWF concentrates devoid of factor 8
what is the most common type of leukaemia in children ?
acute lymphoblastic leukaemia
what is the peak age of diagnosis of acute lymphoblastic leukaemia ?
2-6 years
how may acute lymphoblastic leukaemia present?
- insidious onset of constitutional symptoms and symptoms and signs of anemia
- recurrent infections
- bruising and bone pain (most common presentation)
- hepatosplenomegaly and lymphadenopathy
what are complications of acute lymphoblastic leukaemia
- solid organ involvement: liver, testes (males), CNS, lungs
- mediastinal mass producing obstructive symptoms; dysphagia, dyspnea
- disseminated intravascular coagulation
- tumour lysis syndrome
define tumour lysis syndrome ?
a metabolic syndrome from the rapid lysis of tumour cells that can occur spontaneously or from chemotherapy. oncological emergency
what are the metabolic derangements seen in tumour lysis syndrome ?
high phosphate
high potassium
low calcium
elevated LDH
elevated urea and creatinine due to acute uric acid crystal nephropathy
what is the major complication associated with tumour lysis syndrome?
renal impairment (AKI),
treatment of tumour lysis syndrome?
hyper hydration, loop diuretic in symptomatic hypervolemia, electrolyte correction, rasburicase (urate oxidase enzyme),
patient may require dialysis
diagnosis of acute lymphoblastic leukaemia? Additional investigations for workup
- FBC: pancytopenia
- bone marrow smear looking for blast cells
- chest x-ray, lumbar puncture for CNS tumour spread
management of acute lymphoblastic leukaemia?
- may require blood transfusions – severe anemia
- hydration + allopurinol to protect against tumour lysis syndrome
- chemotherapy (methotrexate + mercaptopurine)
- intrathecal cytotoxic injection for CNS tumour spread
Acute myeloid leukaemia is … common than acute lymphoblastic leukaemia and occurs at a … age
less
older
….. lymphoma is characterized by the presence of …. cells
Hodgkins
reed Sternberg
presentation of Hodgkin lymphoma?
…. lymphomas are more com
…. lymphoma are more common than …. lymphoma in children under 14
non-hodgkin
hodgkin
presentation of Hodgkin lymphoma ?
- painless cervical lymphadenopathy
- mediastinal mass causing obstructive symptoms
- B symptoms: fatigue, anorexia, weight loss, fever
diagnosis of Hodgkin lymphoma? further investigation for staging
- gold standard is lymph node excisional biopsy
- bone marrow aspiration biopsy
- imaging for staging (Ann Arbor) - chest x-ray, CT, PET
non-hodgkin lymphoma have … clinical behaviour in paediatrics population
aggressive
how is treatment response monitored in lymphoma?
PET scan
presentation of non-hodgkin lymphoma?
1.painless lymphadenopathy
2. mediastinal mass causing airway obstruction
3. abdominal obstruction
4. spinal cord compression (3x more common in non-hodgkin lymphoma)
… symptoms are less common in …. lymphoma compared to … lymphoma
B symptoms
non-hodgkin
hodgkin
Burkitt lymphoma is associated with … and … infections
HIV and EBV
define Kawasaki disease?
idiopathic, acute and self limiting vasculitis occurring childhood, more commonly in males
most children who have Kawasaki are under the age of ??
5
diagnostic criteria for Kawasaki disease?
unexplained fever > 38.5 for 5 or more days + 4 out of the 5:
1) mucositis (strawberry tongue)
2) bilateral nonexudative conjunctivitis
3) cervical lymphadenopathy (usually unilateral)
4) polymorphic rash (urticaria or maculopapular – not vesicular)
5) distal extremity changes
Kawasaki is purely a …. diagnosis and by exclusion
clinical
what is the main complication of Kawasaki disease?
coronary artery aneurysm
what investigation is required in all patients with Kawasaki disease? when is it done ?
echocardiogram
at the time of diagnosis, 1-2 weeks and 5-6 weeks
what is the management of Kawasaki disease?
- IV infusion of IVIG on admission
- daily aspirin minimum 6 weeks - Kawasaki disease is one of the few paediatric indications for aspirin
what syndrome is caused by the aspirin in the paediatric population ?
reye syndrome - hepatic failure, cerebral - due to mitochondrial damage. can get seizures
define Henoch-schonlein purpura? age range most commonly occurs in ? what commonly precedes it ?
a systemic vasculitis occurring in children 2-8 tears old, following upper respiratory tract infection resulting in IgA immune complex in small vessels
manifestations of Henoch-schonlein Purpura?
- skin - characteristic purpuric rash (palpable)
- joints - arthralgia
- GI - abdominal pain, bloody stools, vomitting, intussception is a complication
- kidneys - hematuria (glomerulonephritis)
diagnosis of Henoch-schonlein purpura ?
clinical diagnosis. characteristic purpuric rash plus one or more of : nephritis, arthralgia, abdominal pain
management of Henoch-schonlein purpura?
- supportive measures
what single investigation is usually just required in Henoch-schonlein purpura?
urinalysis
what is the management of Henoch-schonlein purpura?
supportive measures
pain control: NSAIDs mild, corticosteroids severe
….. can occur after an URTI, and results in a low platelet count
idiopathic thrombocytopenic purpura
manifestations of idiopathic thrombocytopenia purpura ?
extensive petechia/purpura and mucosa bleeding if severe.
management of idiopathic thrombocytopenia purpura ?
usually mild and resolves in 3 weeks (avoid NSAIDs)
if severe give IVIG and steroids
triad that characterizes hemolytic uremic syndrome?
- microangiopathic hemolytic anemia
- thrombocytopenia
- acute kidney injury
HUS in children mostly occurs after a GI infection with ….?
shiva toxin producing E.coli (STEC)
presentation of HUS?
- abdominal pain
- nausea and vomitting
- abdominal pain
- anemia
- jaundice
HUS usually manifests … - …. weeks after onset of GI symptoms
1-2 weeks
how is hemolytic uremic syndrome diagnosed?
- FBC: anemia and thrombocytopenia
- serum creatinine and urinary output: AKI
- other tests: blood smear (schistocytes), stool culture to identify toxin
- hematuria
- other blood tests which suggest hemolysis: haptoglobin, LDH
Management of hemolytic uremic syndrome?
- ABCs and immediate resuscitation
- monitor vitals especially BP and urinary output, consider dialysis if there is evidence of AKI
- supportive measures: IV fluids
do not give …. and … when managing a patient with hemolytic syndrome because they can make it worse
antibiotics – release of preformed toxin
anti-diarrheal
