Haematology Flashcards
What is the pathophysiology of multiple myeloma?
- Plasma cells are B lymphocytes that have developed to produce a specific antibody (5 types)→ these are molecules made up of heavy chains & light chains.
- Normally a large variety of plasma cells produce various forms of immunoglobulin → in MM, one particular plasma cell clone replicates in an uncontrolled manner. Meaning one antibody is overproduced
- This spike in specific cell clone is seen using urine electrophoresis.
- These plasma cell clones accumulate in the bone marrow, crowding out the normal healthy tissue responsible for producing normal blood cells.
- Additionally, the abnormal plasma cells produce a paraprotein, which is abnormal antibody light chains → these cause damage to kidneys by forming protein casts in the renal tubules.
- The abnormal plasma cells also secrete factors which activate osteoclasts to break down bone, resulting in widespread lytic lesions, bone pain, and hypercalcaemia.
How does multiple myeloma present?
CRABI:
- (hyper)Calcium: Bone pain, stones, abdo groans, psych moans
- Renal failure: SOB/oedema, pruritis, uraemia, AKI
- Anaemia & thrombocytopenia: SOB, fatigue, petechiae
- Bone lesions: back, rib pain
- Infection: recurrent
What investigations are done for multiple myeloma?
Bloods:
- FBC → anaemia, neutropenia, thrombocytopenia
- U&Es → raised creatinine & calcium
- ESR → raised
- Blood film → rouleaux formation
Special tests:
- Serum protein electrophoresis → for paraproteins
- Urine protein electrophoresis → Bence-Jones protein
Bone Marrow Biopsy:
- Confirms the diagnosis → assess the percentage of bone marrow occupied by plasma cells
Imaging:
- Skeletal x-ray → looking for typical lytic lesions, abnormal fractures
- Whole-body MRI
How is multiple myeloma managed?
Treatment aims to control the disease. It takes a relapsing-remitting course & is never fully cured.
Asymptomatic:
- Ie, no signs of end-organ damage
- Watch & wait
Patients <65yrs & ‘Fit’:
- High-dose chemotherapy followed by stem cell transplant
- Autologous → persons own stem cells are harvested prior to chemo & re-inserted
- Allogenic → from a donor
Patients >65yrs & Other Illness:
- Unable to tolerate stem cell transplant
- Chemotherapy alone
What are some triggers for disseminated intravascular coagulation?
- Infection → sepsis
- Shock
- Severe burns
- Malignancy
- Major trauma
- Severe obstetric complications
- Severe organ dysfunction → acute hepatic failure, severe acute pancreatitis
How does DIC present?
- Bleeding from unusual sites → ears, nose, GI, urinary, respiratory, venepuncture/cannulation sites
- Bleeding from 3 unrelated sites is highly suggestive of DIC.
- Widespread or unexpected bruising without a history of trauma
- New confusion or disorientation
- Features of underlying cause
What blood results are seen in DIC?
- FBC → thrombocytopenia
- Coagulation screen → prolonged PT & APTT
- D-dimer → raised, breakdown product of fibrin
How is DIC managed?
- Treat the underlying disorder
- Supportive treatment
- Platelet transfusions → if bleeding & <50
- Fresh frozen plasma → if bleeding and prolonged PT/APTT
How will sickle cell anaemia present on investigations?
- Low Hb/haematocrit/RBCs → vaso-occlusion, haemolysis, splenic sequestration
- Reticulocytosis
- Increased WBC count
- Peripheral blood smear analysis
- Hb electrophoresis → definitive diagnosis (90-95% HbS)
What typically triggers an aplastic crisis in people with sickle cell anaemia?
Parvovirus B19
What is the general management of sickle cell anaemia?
- Avoid triggers for crises → dehydration
- Up-to-date vaccinations
- Antibiotic prophylaxis → phenoxymethylpenicillin
- Hydroxycarbamide → stimulate HbF
- Blood transfusions for severe anaemia
- Bone marrow transplant can be curative
- Folic acid supplementation → increased requirements due to haemolysis.
- Oxygen → often gives symptomatic relief even in patients with adequate saturations.
How does leukaemia present?
Anaemia
- fatigue
- pallor
Thrombocytopenia
- petechiae
- abnormal bruising
- unexplained bleeding
Leucopenia
- recurrent infections
Other
- bone & joint pain
- hepatosplenomegaly
- weight loss
- night sweats
- fever
What type of leukaemia is associated with Down Syndrome?
ALL
What type of blood cancer will show auer rods in the cytoplasm of blast cells on blood film?
AML
What type of blood cancer is often found in asymptomatic patients with an isolated raised WCC?
CLL
