Complete blood count in primary care

1
INTRODUCTION TO AUTOIMMUNITY AND AUTOANTIBODY
TEST
By Madiha Hamid
Horror autotoxicus Literally, the horror of
self-toxicity.

• Tolerance to self Ags is maintained by central
  and peripheral mechanisms.
• Dysregulation in these mechanisms will trigger
  autoimmune disease.

• A family of 80 chronic and disabling diseases
• Affects about 15-23 million people in the USA.

2
Autoimmunity Genetic Factors
CAUSES

• Three main sets of genes are suspected in many
  autoimmune diseases. These genes are related to
• Immunoglobulins
• T-cell receptors
• The major histocompatibility complexes (MHC).

Autoimmunity Environmental Factors

• Following factors can trigger autoimmunity
• Pathogens,
• drugs,
• hormones,
• toxins

Symptoms
Common symptoms may be Fever, muscle ache,
fatigue, joint pain. Each disease has specific
symptom
3
Autoimmunity Can be classified into clusters that
are either organ-specific or systemic
Lungs of a patient with Goodpastures
4
Autoantibody test
Mainly done for the diagnosis of autoimmune
disease. The Antinuclear antibody (ANA) test is
often ordered first. ANA is a marker of the
autoimmune process it is positive with a
variety of different autoimmune diseases but not
specific. If an ANA test is positive, a panel
of 4 or 6 autoantibody tests called extractable
nuclear antigens (ENA) is typically ordered. , it
is often followed up with other tests associated
with arthritis and inflammation, such as a
rheumatoid factor (RF), an erythrocyte
sedimentation rate (ESR), a C-Reactive Protein
(CRP), and/or complement protein complement
levels.
The AMA test is ordered to help diagnose primary
biliary cirrhosis (PBC).These abs are detedtced
by indirect immunoflourescence in gt 90 of
patients.Reference range is lt0.1 -1.0 units.
APA testing is used to help determine the cause
of Inappropriate blood clot formation
(unexplained thrombotic episode, excessive
clotting) Recurrent miscarriage Low platelet
count (thrombocytopenia) Prolonged PTT test
A cyclic citrullinated peptide (CCP) antibody
test may be ordered along with or following
a rheumatoid factor (RF) test to help
diagnose rheumatoid arthritis (RA) and to assess
the severity and probable course of the disease
(prognosis).
5
C-Reactive Protein Complement Levels

• Gul Sanober

6
C-reactive protein (CRP) test

• a non-specific marker produced by the liver
• increases during episodes of acute systemic
  inflammation
• measured by blood tests.
• Some forms of arthritis
• Autoimmune diseases, such as lupus or vasculitis
• a CRP level of 10 mg/L or lower is considered
  "normal."

7
Complement Levels

• most commonly C3 and C4
• Synthesized in the liver
• Measured through blood tests
• Normal levels
• C3
• Males 88-252 mg/dL
• Females 88-206 mg/Dl
• C4
• Males 12-72 mg/dL
• Females 13-75 mg/dL
• Levels decrease in autoimmune disorders(Hypocomple
  mentemia)

8

• Diagnose and monitor
•  acute or chronic autoimmune diseases such
  assystemic lupus erythematosus (SLE)
• immune complex-related diseases and conditions
  such as glomerulonephritis, serum
  sickness, rheumatoid arthritis, and vasculitis
• Individual complement components ordered when the
  total complement activity (CH50 or CH100) is
  abnormal to help determine which of the
  component(C1 to C9)s are deficient or abnormal

9
Considerations

• Serum is preferred
•  All samples must show no signs of deterioration
  and lipaemic samples should be avoided.
• Samples may be stored at 4C prior to analysis
• Acute malarial infection can cause false-positive
  results
• Complement component 3 has been shown
  to interact with Factor H.

10
Rheumatoid factor - RF

• 
  By Namra Haq

11
Rheumatoid factor explained
Rheumatoid factor is an immunoglobulin (antibody)
which can bind to other antibodies. Antibodies
are normal proteins found in the blood which
function within the immune system. Rheumatoid
factor though is not normally found in the
general population (only found in about 1-2 of
healthy people). The incidence of rheumatoid
factor increases with age and about 20 of people
over 65 years old have an elevated rheumatoid
factor.
A blood test is used to detect the presence of
rheumatoid factor. The blood test is commonly
ordered to diagnose rheumatoid arthritis.
Rheumatoid factor is present in 80 of adults who
have rheumatoid arthritis but there is a much
lower prevalence in juvenile rheumatoid
arthritis. The incidence of rheumatoid factor
increases with duration of disease in rheumatoid
arthritis at 3 months the incidence is 33,
while at one year it is 75. Up to 20 of
rheumatoid arthritis patients remain negative for
rheumatoid factor (also known as "seronegative
rheumatoid arthritis") throughout the course of
their disease.
12
Other conditions in which RH is positive apart
from rheumatoid arthritis
Other autoimmune diseases can also be positive
rheumatoid factor including Sjogrens Syndrome,
Systemic Lupus Erythematosus, Scleroderma,
Polymyositis, Dermatomyositis, Mixed Connective
Tissue Disease
Other infections or conditions which can be
associated with positive rheumatoid factor
include Bacterial Endocarditis, Osteomyelitis,
Tuberculosis, Syphilis, Hepatitis, Mononucleosis,
Liver Cirrhosis, etc.
Conditions not associated with RF
Rheumatic conditions NOT associated with elevated
rheumatoid factor include Osteoarthritis, Gout,
Reiter's syndrome / Reactive arthritis, etc.
13
How is RF factor measured?
The amount of rheumatoid factor in blood can be
measured by Agglutination tests One method
mixes the patient's blood with tiny latex beads
covered with human antibodies (IgG). The latex
beads clump or agglutinate if rheumatoid factor
(IgM RF) is present. Another method mixes the
patient's blood with sheep red blood cells that
have been covered with rabbit antibodies. The red
blood cells clump if rheumatoid factor is
present. A titer is an indicator of how much the
agglutination test blood sample can be diluted
before rheumatoid factor is undetectable. A titer
of 120 indicates that rheumatoid factor can be
detected when 1 part of blood is diluted by up to
20 parts saline. The lab value for rheumatoid
factor of 120 or less is considered normal.
14

• Nephlometry test
• This method mixes the patient's blood with
  antibodies that cause the blood to clump if
  rheumatoid factor is present. A light is passed
  through the tube containing the mixture and an
  instrument measures how much light is blocked by
  the mixture. Higher levels of rheumatoid factor
  create a more cloudy sample and allow less light
  to pass through, measured in units. The lab value
  for rheumatoid factor of 23 or less units is
  considered normal.
• When analyzing lab results the following should
  be considered
• A rheumatoid factor more than 23 units and a
  titer more than 180 is indicative of rheumatoid
  arthritis but may also occur in other conditions.
• False positive results can occur when the blood
  is high in fats.
• Inaccurate results can be caused by improper
  handling of the blood specimen.
• A negative test result for rheumatoid factor
  does not exclude the diagnosis of rheumatoid
  arthritis.

15
Erythrocyte Sedimentation Rate Test (ESR / Sed
Rate)

• Marker of Inflammation-autoimmune diseases like
  lupus or rheumatoid arthritis cause inflammation.
• Nonspecific Test
• Not used for screening purpose (low senstivity
  and specificity)
• Inexpensive
• Uses
• a. Diagnosis(auto-immune diseases ,rheumatoid
  arthritis, chronic kidney diseases)
• b. Disease severity
• c. Monitoring response to therapy ( inflammatory
  diseases such as temporal arteritis, polymyalgia
  rheumatica and rheumatoid arthritis)

16
Erythrocyte Sedimentation Rate Test (ESR / Sed
Rate)

• Measure of the settling of red blood cells in a
  tube of blood during one hour.

• When abnormal proteins are present in the blood,
  typically due to inflammation or infection, they
  cause red blood cells to clump together and sink
  more quickly.

17
Erythrocyte Sedimentation Rate Test (ESR / Sed
Rate)
Autoimmune Disorders
Higher than Normal

• Factors That May Influence ESR
• Increase ESR
• Old Age
• Pregnancy
• Anemia
• Macrocytosis
• Decreased ESR
• Extreme leukocytosis
• Polycythemia
• Red blood cell abnormalities

• Very high ESR levels
• Allergic vasculitis
• Giant cell arteritis
• Polymyalgia rheumatica

Reference Age Adults Upper limit of reference
range (mm/hr) Age lt 50 years Men 0 to
15 Women 0 to 20 Age gt 50 years Men 0 to
20 Women 0 to 30
18
Secret Blood Test of Autoimmune Disease
TH1 / TH2 Cytokine Test  The
immune system works like a seesaw. On one side
you have Th1 cytokines that initiate the first
line of defense. On the other side you have Th2
cytokines which help product antibodies to
protect you from future invasions. However, when
one side goes up, the other side goes down. This
can contribute to a weak immune system and
potentially promote autoimmune conditions. 
19
Complete blood count in primary care
20
PRINCIPLE

• This test measures red blood cells and white
  cells. The test includes red blood cell count,
  hemoglobin, hematocrit, MCV, MCHC, RDW, platelet
  count, white blood cell count, neutrophils,
  lymphocytes, monocytes, eosinophils and basophils.

21
Phisiology

• Whole blood collected in EDTA (purple top tube)
  is the only acceptable specimen. The
• specimen must be kept and transported at room
  temperature. For best results, the
• collection tube should be full and no less than
  half full. Mix the specimen slowly for 2
• minutes.
• Unacceptable specimens include
• Any sample not collected in an EDTA tube.
• Any tube less than half full
• Any tube that is not labeled properly
• Hemolyzed specimens
• Specimens older than 24 hours
• Specimens that are clotted
• METHOD VCS Technology, Hemoglobinometry

22
Significance

• Screen for a wide range of conditions and
  diseases
• Help diagnose various conditions, such as anemia,
  infection, inflammation, bleeding disorder or
  leukemia, to name just a few
• Monitor the condition and/or effectiveness of
  treatment after a diagnosis is established
• Monitor treatment that is known to affect blood
  cells, such as chemotherapy or radiation therapy
• A CBC is a panel of tests that evaluates the
  three types of cells that circulate in the blood
  and includes the following
• Evaluation of white blood cells, the cells that
  are part of the body's defense system against
  infections and cancer and also play a role in
  allergies and inflammation
• Evaluation of red blood cells, the cells that
  transport oxygen throughout the body
• Evaluation of platelets, cell fragments that are
  vital for normal blood clotting

23
ULTRASOUND

• gt20,000 Hertz OR more
• Diagnostic Medical Ultrasound - use of high
  frequency sound waves to aid in the diagnosis and
  treatment
• Frequency ranges -gt 2 - 15 MHz
• Piezoelectric Effect The principle of
  converting energy by applying pressure to a
  crystal
• Pulse-echo principle, ultrasound transducers
  convert 1 type of energy to another
• Electricity into sound pulse machine to
  tissue
• Sound into electricity echo tissue to
  machine
• Echoes are interpreted and processed by the
  ultrasound machine

24
X-RAYS

• Digital Radiography, High Frequency Radiography
  Unit help in diagnosis
• Electro magnetic radiations ELECTRONS
• High-speed flow of electrons bombarding the anode
  target surface, 99 converted to heat, to produce
  X-ray - 1 (50Hz or 60Hz)
• Useful in detection of pathology of the skeletal
  system
• Bones contain much calcium hence absorb x-rays
  efficiently reduces amount of X-rays reaching
  detector in the shadow of the bones making them
  clearly visible on the radiograph
• In medical diagnostic applications, low energy
  (soft) X-rays are unwanted since they are
  totally absorbed by the body, increasing the
  radiation dose without contributing to the image
• A thin metal sheet, often of aluminium, an
  X-ray filter, usually placed over the window of
  the X-ray tube, absorbing the low energy rays.
  Center of the spectrum shifts toward higher
  energy hardening the beam Hard X-rays

25
BIOPSY

• Medical test performed by surgeon involving
  sampling of cells or tissues for examination.
  TISSUE SAMPLING
• Medical removal of tissue from a living subject
  to determine the presence or extent of a disease.
• Frequent biopsies are taken to assess activity of
  disease and to assess changes that precede
  malignancy.
• Examined under a microscope or analyzed
  chemically by a pathologist.
• Entire lump or suspicious area is removed
  Excisional biopsy.
• Sample of tissue is removed with preservation of
  the histological architecture of the tissues
  cells Incisional biopsy or core biopsy.
• Scanner's images help doctors determine exact
  position of the needle in the targeted tissue
  CT-guided biopsy.
• An ultrasound scanner helps a doctor direct the
  needle into the lesion. Ultrasound-guided
  biopsy.
• A needle withdraws material out of a mass.
  Aspiration biopsy.

26
(No Transcript)
27
THANK YOU