Pathology

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Pathology
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Definition

• Study of structure functional changes in
  tissues or organs which cause or are caused by
  disease

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Branches of Pathology
Haematology study of blood i.e. nature, function diseases of the blood
Histology study of structure, function of body tissues
Immunology study of Immunity the bodys defense mechanisms
Cytology study of the form functions of body cells
Biochemistry chemical composition of blood
Microbiology study of microorganisms
Bacteriology study of bacteria
Serology study of serum
Clinical pathology laboratory testing for diagnosis
Surgical pathology use of surgery to diagnose
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Collection of specimens
Aspiration drawing off fluid from a body cavity
Venepuncture puncture of a vein to withdraw blood specimen
Biopsy removal of tissue for examination to establish a diagnosis
Swab a gauze coated stick used to take bacterial specimens
Faecal fat analysing faeces of fat content
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Examination
Culture and sensitivity growth of microorganisms in special medium to test for specimens reaction to agents e.g. antibiotics
Microscopic appearance appearance of organisms or tissue under magnification
Blood Count number of blood cells in a given sample of blood
In vitro in a glass observations made outside of body
Autopsy examination of the body after death
In vivo observation made within the body
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Abbreviations
CS culture sensitivity Chol cholesterol
MSU mid stream urine BUN blood urea nitrogen
GTT glucose tolerance test U/A urinalysis
LFT liver function test ESR erythrocyte sedimentation rate
LP lumbar puncture FBSL fasting blood sugar level
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Pathology results

• As an office worker you are required to identify
  
• The patients identity i.e name, medical /
  reference number
• The doctor who ordered the test
• The type of sample
• When the sample was collected
• The doctor will sign the report when the results
  have been reviewed by him/her

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Haematology
Full Blood Count (FBC) Full Blood Examination (FBE) Determines the amount of red white blood cells per cubic metre
Haemaglobin (Hb) Measures the protein iron in blood that carries oxygen
Haematocrit (Hct) Measures the packed cell volume of red blood cells
Prothrombin index (PI) measures the amount of time it takes blood to clot
Erythrocyte Sedimentation Rate (ESR) measures the rate at which red blood cells settle in unclotted blood
Prostate Specific Antigen (PSA) detects presence of specific antigen that increase in prostate cancer
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Haematology
Blood group cross match (Gp X Match) Classifies blood then determines compatibility between donor and recipient
Serology Testing Is applied for venereal diseases e.g. used in AIDS screens for antigens or antibodies to human immunodeficiency virus (HIV)
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Biochemistry

• Electrolytes and organic acids are essential for
  normal body function metabolism
• Examples include sodium, potassium, magnesium,
  chloride, bicarbonate, calcium
• Can be measured in blood serum
• Abnormal levels in blood can indicate tissue
  damage or various disorders

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Lipids

• Cholesterol
• Fatty acids
• Triglycerides
• NB Elevated levels can indicate disease, e.g.
  arteriosclerosis

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Biochemistry
Urinalysis examines the chemical properties of urine
Creatinine test measures the amount of creatinine in the urine. If elevated can indicate disturbance in kidney function
Creatinine Clearance Measures the rate at which kidneys remove creatinine from the blood
Liver Function Teats (LFTs) abnormal levels indicates damage and presence of liver disease
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Cytology

• Study of formation, origin, structure, pathology
  of cells
• E.g. Cells can be taken from cerebrospinal fluid
  lung bronchi, gastric fluid, bone marrow, cervix

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Histopathology / histology

• Study of tissue to identify presence of disease
• Biopsy small piece of tissue is obtained for
  examination
• Removal of part or all of an organ for
  examination
• Frozen Section tissue removed at time of
  surgery examined under microscope for a quick
  diagnosis before continuing the surgical
  procedure

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Bacteriology

• Study of disease produced by bacteria
  (microscopic plants some can produce disease)
• Uses specimens of blood, urine, spinal fluid,
  faeces or any body secretion
• Cultures isolate infective organisms which grow
• They can then be tested to determine an
  antibiotic that will destroy the organisms