Clinical & Laboratory Assessment Dr Roger Pool NHLS & University of Pretoria Clinical Assessment (History) Anaemia ( haemoglobin) Dyspnoea (shortness of breath) Tiredness Angina Headache
Clinical Assessment (History) Leucopenia ( white cell count) Frequent bacterial infections (skin, mouth, throat, chest) Viral infections, TB Infections are atypical, rapidly progressive & difficult to treat Clinical Assessment (History) Thrombocytopenia ( platelet count) Bruising, epistaxis, menorrhagia Bleeding following trauma increased when platelet count < 50 X 10 9 /l Spontaneous bleeding when platelet count < 10 X 10 9 /l Coagulation factor defects ( coagulation factors) Bleeding following dental extraction Deep tissue bleeding Family history
Additional History Weight loss, fever Bone pain, left hypochondrial pain Lymphadenopathy Family history Drug history Previous operations Physical Examination Pallor Tachycardia, systolic murmur Jaundice Lymphadenopathy Skin changes purpura, ankle ulcers Nail changes koilonychia Signs of infection Hepatomegaly and/or splenomegaly Neurological examination B 12 neuropathy Optic fundi anaemia, hyperviscosity
Figure 6.1 Haematology at a Glance Petechiae (typical of platelet disorders) Do not blanch with pressure Not palpable
Laboratory Assessment Full blood count (FBC) Erythrocyte sedimentation rate (ESR) Coagulation profile Bone marrow aspirate & trephine Flow cytometry Chromosome analysis (cytogenetics, FISH) Full Blood Count (FBC) Collected into EDTA (purple stopper) Hb, Hct, red cell count White cell count + differential count Red cell indices (MCV, MCH, MCHC) Platelet count Blood film size and shape of cells, malaria, leukaemia
Erythrocyte sedimentation rate (ESR) Measures the rate of fall of a column of red cells in plasma in 1 hour Determined by plasma concentration of proteins Raised in anaemia Non specific indicator of disease activity ESR infection, inflammation, malignancy, pregnancy
Bone marrow aspirate and trephine biopsy Indications: Unexplained anaemia, leucopenia or thrombocytopenia Suspected bone marrow infiltration Suspected infection e.g. TB
Flow cytometry Technique used to identify antigens on cell surfaces using a laser light and flourescent dyes Used in the diagnosis of leukaemia Used to monitor residual disease after treatment
Flow Cytometer Chromosome analysis Chromosome abnormalities are seen in leukaemia and myelodysplastic syndromes FISH (flourescent in situ hybridization) a technique used to identify specific chromosomal abnormalities e.g. translocations
Coagulation profile Prothrombin time (PT) measures the extrinsic and common coagulation pathways Prolonged in liver disease, warfarin therapy, DIC Activated partial thromboplastin time (APTT) measures the intrinsic and common pathways Prolonged in liver disease, heparin therapy, DIC, haemophilia
Benign Disorders of White Blood Cells
Neutrophil Neutrophil leucocytosis Bacterial infection Inflammation Trauma or surgery Tissue necrosis or infarction Neoplasia Haemorrhage or haemolysis Metabolic derangement Myeloproliferative disease Pregnancy Drugs (steroids, G-CSF)
Neutropenia Decreased Production General bone marrow failure Aplastic anaemia, myelodysplasia, acute leukaemia, chemotherapy Specific failure of neutrophil production Congenital, cyclical, drug induced Increased Destruction General Hypersplenism Specific Auto-immune Lymphocyte
Lymphocytosis Viral infection Certain bacterial infections e.g. pertussis Lymphoproliferative disorders (leukaemia, lymphoma) Lymphopenia HIV infection Hodgkin s lymphoma Auto-immune disease (e.g. SLE) Cortisone therapy Severe bone marrow failure
Eosinophil Eosinophilia Allergy Parasitic infestation Chronic skin disease