FBC abnormalities

Sx: fatigue, pallor (skin, conjunctivae), chest pain, SOB, koilonychia

Often insidious.

Ix: Hx (duration of Sx, bleeding- menorrhagia, GI, PR), look at MCV (micro/normo/macrocytic), haematinics (B12, folate, iron studies), reticulocytes

Microcytic: iron deficiency, thalassaemia

Macrocytic: B12/folate (most common, can cause pancytopenia), abnormal thyroid function, high reticulocytes (haemolysis), liver disease, pregnancy, myelodysplastic syndrome

Normocytic: anaemia of inflammation, mixed picture (iron and B12/folate deficiency), myeloma

Low ferritin: iron deficiency (what is the cause? menstruation, think bowel cancer if older patient)

Ferritin may be high even if iron is low (acute phase reaction in inflammation)

Total iron binding capacity- high in iron deficiency, low in haemochromatosis

Serum iron: low in deficiency, high in haemochromatosis

HFE gene (haemochromatosis)

Mostly due to mutation of HFE gene (chrmosome 6p). Autosomal recessive (penetrance varies)

Organs affected by iron deposits: liver, pancreas, joints, heart, skin, gonads

Most serious complications: liver fibrosis, cirrhosis, HCC

Presentation: may be incidental (high ferritin/abnormal LFTs), usually age 40-60 (males) and postmenopausal (females), non-specific initial Sx (fatigue, weakness, arthropathy, heart problems, erectile dysfunction)

Advanced disease: diabetes, bronze skin, hepatomegaly, arthropathy, impotence, amenorrhoea, hypogonadism, cirrhosis, cardiac disease (arrhythmias, cardiomyopathy), impaired memory, mood swings, irritability, depression

Indications for genetic testing: chondrocalcinosis, diabetes, liver disease, raised ferritin, transferrin saturations > 45%, high serum iron, abnormal LFTs, 

Rx: regular phlebotomy (weekly-2 weekly), treat complications, chelation therapy if needed (deferasirox)

Often associated with autoimmune disease (autoimmune haemolytic anaemia). 

Also caused by hereditary spherocytosis: autosomal dominant, often presents in children, splenomegaly +/- abdo pain, some need no treatment, if need Rx then splenectomy (try to wait until they are old enough to be immunised against encapsulated organisms- pneumococcus, meningococcus, H. influenzae), need low-dose prophylactic Abx for rest of life

Other causes of haemolysis: G6PD deficiency (X linked, may be precipitated by drugs/infection), malaria, mechanical problems (e.g. valve disease)

Ix: raised bilirubin, decreased haptoglobins, raised reticulocytes, direct antibody test (DAT/direct Coombs test- are there Abs present on RBCs)

Clonal plasma cell (make immune cells) neoplasm, usually accompanied by monoclonal Abs production (paraproteins- can cause end-organ damage)

End organ damage: CRAB (hyperCalcaemia, Renal impairment, Anaemia, lytic Bony lesions)

Check for bony lesions with MRI

Characterised by monoclonal protein in serum and/or urine, lytic bone lesions, and XS plasma cells in BM

Ix: serum free light chains (more expensive), serum and urine electrophoresis (Benz-Jones proteins)

Leukocytosis: reactive (inflammation, infection), primary BM problem

Leukopenia: haematinic deficiency (B12, folate), primary BM problem

Thrombocytosis: often reactive, look for markers of inflammation, look at trend of platelets, check for underlying cause, rarely BM problem

Thrombocytopenia: decreased production (haematinic deficiency, acute leukaemia, myelodysplastic syndrome), increased consumption (DIC, sepsis, immune mediated- ITP)

ITP: Dx of exclusion, elevated megakaryocytes in BM, treat with steroids (careful in children)

DIC: patient is sick, use up all clotting factors, decreased fibrinogen and platelets, raised PT + APTT, need to replace clotting factors and platelets

Types:

• polycythaemia vera (mostly RBCs, can affect all)
• essential thrombocytosis (mostly platelets)
• myelofibrosis (all cells)
• chronic myeloid leukaemia (mostly WBCs)

Reactive or MPN? Hx, trend of platelets (duration), inflammatory markers

Often an incidental finding (raised RBCs)

Increased risk of thrombosis and stroke. Usually asymptomatic, but may present with itc h and splenomegaly.

Average age at Dx: 60

1st look for underlying secondary causes: smoking, alcohol, use of testosterone, living at high altitudes, chronic hypoxia, exogenous Epo production

If no secondary causes, investigate for polycythaemia vera: JAK2 mutation positive in 95% people with polycythaemia vera (upregulation of tyrosine kinase signalling)

Treatment: aspirin, venesection, may need low dose hydroxycarbamide (can cause ulcers)

Exclude reactive cause

Test for JAK2, MPL and calreticulin (genetic abnormalities).

If negative for genetic abnormalities, need BM biopsy

Treat with aspirin. If risk factors for thrombosis (including age >60), may need cytoreduction

Presents with sweats, splenomegaly and cytopenias

Can occur alone, but may progress from essential thrombocythaemia/polycythaemia vera

Treatment: supportive care, cytoreduction, JAK2 inhibitors, ?BM transplant

PHILADELPHIA CHROMOSOME (9:22 translocation, BCR:ABL)

Commonly an incidental finding

May present with leucostasis (including visual symptoms), splenomegaly, fatigue, night sweats, wt loss

Often have leucocytosis, may have normocytic normochromic anaemia

Rx: tyrosine kinase inhibitors (s/e include pleural effusion), need to monitor PCR, can consider BM transplant

Activate massive haemorrhage protocol by phoning the blood bank

Important to group and cross-match (give O-negative while waiting)- need 2 samples separated by time (and preferably also taken by different people) with patient details filled in by the bedside- risk of wrong patient!

Need to give lots of blood products e.g. plasma, platelets

Check PT + fibrinogen (also check fibrinogen in DIC)

Concerns around transfusion- screening for BBV etc