Presentation on theme: "Anaemia that isn’t due to iron deficiency Dr Annette Nicolle Consultant Haematologist Queen Elizabeth Hospital/ Sunderland Royal Hospital."— Presentation transcript:
Anaemia that isn’t due to iron deficiency Dr Annette Nicolle Consultant Haematologist Queen Elizabeth Hospital/ Sunderland Royal Hospital
Objectives Look at the wide differential diagnosis of anaemia Discuss some clinical cases Look at laboratory pitfalls, and questions commonly asked
Thought for the day “Many of us talk in our sleep. The distinctive achievement of lecturers is to talk in other people’s sleep” –Raymond Tallis
Laboratory results suggestive of anaemia Hb<11.5 g/dl for females Hb<13.0 g/dl for males Hb<11.0 g/dl for F with rheumatoid arthritis Hb<11.0 g/dl for M with rheumatoid arthritis NB – take into account previous Hb level
The Med School Version
Blood vessels Liver and spleen Bone Marrow Intravascular Haemolysis Causes of Anaemia “Pooling” Antibodies Iron deficiency EXERCISE How many causes of anaemia can you come up with? I’ve started you off
Blood vessels Liver and spleen Bone Marrow Shortage of raw materials Blood Loss Intravascular Haemolysis Extravascular Haemolysis External insults Intrinsic Marrow Problems Reduced Erythropoeitin Renal system Rapid turnover Causes of Anaemia “Pooling” Mechanical damage Antibodies “Abnormal Genes” Anaemia of chronic disease
Case 1 See envelope set 1 Personnel: Patient: Mike Tucker – 56 years old GP: BMS in the lab (Multitalented) “Greek Chorus” – everybody else
The rules The consultation exercise is run by the GP and patient The BMS in the lab can only answer questions – he/she cannot volunteer information The GP can refer to the Greek chorus to seek opinions at any stage by calling a time-out
Case 1 Summary Polymyalgia Rheumatica Key features –History – limb girdle stiffness, extreme tiredness –Microcytic anaemia –High ESR –Inflammatory features – high platelets, raised immunoglobulins –Retics low – indicate reduced marrow output Anaemia of Chronic disease
Microcytic anaemia MCV<80 Iron deficiency Reduced Iron availability –Anaemia of chronic disease Small print: Reduced Haem synthesis –Lead poisoning Reduced globin production –Thalassaemia –Other haemoglobinopathies
Case 2 Helen Archer - first pregnancy antenatal screening bloods: –WBC 7.2 –Hb 12.9 –MCV 62.3 (80-102) –MCH 19.2(27-32) –Plt 251 Any thoughts?
Case 2 Ferritin 73 Next step? Haemoglobinopathy screen –HbA/A –HbA 2 4.0% –Consistent with Beta thal trait Significance?
Case 3 Envelope set 2 Personnel: Patient: Linda Snell 63 years old GP: BMS in the lab (Multitalented) “Greek Chorus” – everybody else Same rules apply
Case 3 discussion Macrocytic anaemia which had a wide differential diagnosis from history –Insidious onset –Family history –Pancytopenia –Note other clinical features of pernicious anaemia– not often present, but very useful when they are However – need sense of perspective when investigating macrocytic anaemia
Aetiology of macrocytosis in 300 patients with an MCV >99fl Prevalence (%) Drugs (cytotoxics, anticonvulsants, anti- retrovirals ) 37 Alcohol (+/- liver disease)26 Reticulocytosis (haemolysis or bleeding)8 Vit B12 or folate deficiency6 Non-alcoholic liver disease6 Primary bone marrow disorders (eg MDS, AML) 6 Hypothyroidism0.6 BMJ 2009;338:1644
Normocytic Anaemia Early iron deficiency Acute blood loss Anaemia of chronic disease (may be microcytic) Renal Failure Cancer Haemolysis (or may be macrocytic) Bone marrow suppression/ disorders Combined haematinic deficiencies
Renal Anaemia GFR <60 = CKD possible cause of anaemia GFR <30 (<45 in diabetics) = CKD is likely to be the cause Should not be assessed until iron deficiency corrected Can measure serum erythropoietin in clinic
Anaemia of Chronic Disease Protective mechanism to reduce availability of iron where it may have a detrimental effect Reduced availability of essential nutrient for bacteria and tumour cells Anaemia limits oxygen transport which affects rapidly proliferating tissues/ organisms Reduced serum iron also increases immune response
Anaemia of Chronic Disease Reduced erythropoietin responsiveness and production Reduced transferrin synthesis Reduced Fe mobilisation from macrophages –Low serum iron despite adequate tissue stores –Reduced iron re-utilization in erythropoiesis –Raised serum ferritin –Reticulocytopenia
Ferritin SERUM FERRITIN is now a standard diagnostic test for Iron deficiency anaemia only iron deficiency will give a low result. A value <15 μg/L is diagnostic of IDA.
Ferritin Iron deficiency anaemia can occur with a normal or high ferritin: Liver dysfunction: ferritin is released when hepatocytes are damaged Increased haem turnover: haemolysis and trauma (including surgery) Inflammatory lesions: malignancy, infection and inflammation
SERUM IRON and TOTAL IRON BINDING CAPACITY (TIBC) In iron deficiency the serum iron is low ( 70 μmol/L). Erythropoiesis is iron-deficient when the transferrin saturation (SI TIBC x 100%) falls below 15%.
Soluble transferrin receptor ratio Available in some hospitals in the region Serum transferrin receptor-ferritin ratio –better for distinguishing between iron deficiency and anaemia of chronic disease –Ratio 2 iron deficiency
Type of anaemia Blood filmFerritinIronTIBCsTfR – ferritin ratio Anaemia of chronic disease Normocytic, normochromic Normal or raised Low <1 Early Iron Deficiency Hypochromic, mild anisocytosis Normal or Low LowRaised>2
Problems with B12 levels Serum B12 is not a good indicator of total body stores Low serum levels without a true deficiency –OCP, pregnancy, iron deficiency, atrophic gastritis False normal B12 levels –Myeloproliferative disease, hepatoma, acute liver disease, high titre IF Abs Have to use the result in clinical context
Problems setting the B12 range… B12 assay curve –Setting lower end of range is difficult Normal distribution curve -applies to most lab tests
ALGORITHM FOR REPORTING B12 AND FOLATE RESULTS B12 > 197 pg/ml. No need for comment pg/ml. Borderline low B12 - probably not clinically significant pg/ml - Low B12. Not macrocytic: Check IFA: if positive, treat as PA If negative, consider oral Rx (unless gastric or ileal resection) and check response
ALGORITHM FOR REPORTING B12 AND FOLATE RESULTS pg/ml - Low B12. If macrocytic: Advise trial of IM B12. If response, continue as for PA < 100pg/ml - Low B12. Advise IM B12 therapy, check response. Diagnosis: ? PA (check IFA), ? Crohn’s, ? gastric or ileal resection
Problems with folate levels (Labs do either serum or red cell folate) False normal serum folate -folate deficient patient who has had a few folic acid tablets False low serum folate – recent alcohol False normal red cell folate – recent transfusion False low red cell folate – primary B12 deficiency
ALGORITHM FOR REPORTING B12 AND FOLATE RESULTS Folate > 4.0ng/ml - no need for comment ng/ml - no need for treatment unless macrocytic and B12 normal, in which case advise trial of treatment and check response < 2.2ng/ml – trial of treatment –? dietary deficiency. –Consider coeliac or other small bowel disorder or resection, anti-folate medication
Reticulocytes The reticulocyte count (retics) reflects the bone marrow's response to anaemia. A low retic count indicates bone marrow hypoplasia. Reticulocytosis (high retic count) indicates the marrow is still responding
Case 4 – Kate Aldridge 1 week history of flu-like illness Fainted a couple of times Now dizzy every time she stands up WBC 7.6 Hb 4.1 Plt 282 Further investigations?
Further investigations MCV 80 Iron 9.0 Bilirubin 10 Retics 10 LDH 200 Normal renal function Now what do you do?
Blood film Normal film Patient’s film
More results Spherocytes on film No evidence of malignancy/ marrow infiltration How does that fit with your differential diagnoses? Other tests?
Other tests Parvovirus serology Confirm Hereditary spherocytosis Family history?
“Aplastic” crisis Parvovirus B19 IgM positive Treatment –transfused as very symptomatic –Folic acid, iron (tests showed iron 9.0) 24/12/0825/12/0826/12/0829/12/08 Hb Retics
Lab evidence of haemolysis Increased reticulocyte count Increased bilirubin DAT (Direct Antibody test) – Coombs test low serum haptoglobin Increased LDH Film appearances Haemoglobinemia/ Haemoglobinuria Haemosiderinuria NB – Red cell autoantibodies are common 3% over 70s have a positive DAT – it does not necessarily cause haemolysis
Marrow Problems Anaemia may be secondary to Marrow infiltration –Cancer, Leukaemia, Lymphoma, inflammatory conditions, infections, fibrosis, Ineffective/ reduced production –MDS, Aplastic anaemia, Inflammatory conditions, infections, DRUGS, anorexia Call your friendly local Haematologist…….
Case 5: Adam Macy Blood film – What is causing his anaemia
Summary Useful points –Remember anaemia of chronic disease – infection/ inflammation –Renal Impairment –Reticulocyte count – tells you marrow function –Combined haematinic deficiencies - can mask each other –Historical results are useful, and rate of change –Lab tests are not infallible
Any Questions? Thankyou
Blood vessels Liver and spleen Bone Marrow Intravascular Haemolysis Causes of Anaemia “Pooling” Antibodies Iron deficiency
Other abnormal Haematology results When to refer and when to relax…
Haematology laboratory results Haemoglobin (erythrocytosis) Hb > 18.5, Hct >0.55 (M), Hb > 16.5, Hct > 0.50 (F) If only Hb raised, consider hypoxia, smoking, alcohol, dehydration and correct if possible If erythrocytosis persists, consider referral If accompanied by raised neutrophils and/or platelets, check if itching, sweating, splenic discomfort, gout, etc. Refer to haematology if PRV/MPD seems likely (JAK2, etc)
Haematology laboratory results White cells Neutrophils < 1.5 Consider whether secondary to medication, auto- immune disorder, hypersplenism, race or viral infection If remains unexplained, refer to haematology (possible need for bone marrow biopsy) Low lymphocyte or monocyte count - no specific referral criteria, but consider HIV if lymphocytes reduced, with appropriate clinical history
Haematology laboratory results White cells Neutrophils > 10.0, persisting for at least one month Exclude latent infection or inflammation, medication (esp. steroids) If accompanied by raised eosinophils and/or basophils, consider referral (? CML) If accompanied by monocytosis, consider referral (? CMMoL) If isolated neutrophilia but unexplained upward trend, consider referral
Haematology laboratory results White cells Lymphocytes > 10.0, persistent for at least one month Consider infection, esp. IM or pertussis Laboratory will arrange cell markers when appropriate, and may then advise referral Monocytes >2.0, persistent for at least one month Consider chronic infection, e.g. TB If accompanied by anaemia and/or neutropenia, neutrophilia or thromoboctyopenia, refer to haematology
Haematology laboratory results Platelets Platelets >600, persistent for at least one month Exclude blood loss, chronic infection or inflammation, prescribe low dose aspirin if no contra-indication If no obvious cause, refer to haematology Platelets do not refer, monitor to detect trend Platelets consider medication, auto-immune disorder, hypersplenism. Do not refer to haematology unless symptomatic Platelets <50 - consider referral to haematology unless cause is clear and/or more relevant to another speciality
Haematology laboratory results Coagulation tests Consider referral to haematology if patient symptomatic (bruising or bleeding) and abnormalities not secondary to anticoagulation, dietary deficiency or known liver disease: PT > 18 secs APTT > 40 secs - N.B. exclude lupus “anticoagulant” Fibrinogen <1.0g/l Any combination of abnormal coagulation results accompanied by relevant symptoms