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Malaria in Pregnancy Anaemia in Pregnancy

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					  Immunity and Diseases
Scientific background to autoimmune
                  diseases


               Dr Michael F. Ofori
 Noguchi Memorial Institute for Medical Research
           College of Health Sciences
               University of Ghana
Autoimmune diseases result when the
 immune system attacks the body's own
 organs, tissues and cells.

Physicians and scientists have identified a
 number of different autoimmune diseases.

  Some are well known,
  Others are less familiar,
   Tolerance and Autoimmunity
The Immune system could go awry and
 instead of reacting only against foreign
 antigens, could focus its attack on SELF
 ANTIGENS

This can result in a number of chronic and
 acute diseases including
    Rheumatoid Arthritis
    Multiple screlosis
    Lupus Erythematosis
    Certain types of Diabetes
 Types Of Autoimmune diseases


Physicians and scientists have identified
 more than 80 different autoimmune
 diseases.
  Some are well known,
     rheumatoid arthritis,
     multiple sclerosis,
     type 1 diabetes
     systemic lupus;
  others are less familiar,
     autoimmune hepatitis,
      Sjögren's syndrome
      pemphigus
 WHY THIS?

The results of the failure of the host’s
 humoral and cellular immune system to
 distinguish SELF from NON-SELF

This will result in the attack of self cells and
 organs by Auto-antibodies and self reactive
 T-cells.
 WHAT IS AUTOIMMUNITY?

This is referred to the inappropriate
 response of the immune system against
 self components .


Autoimmune reactions can cause
 serious damage to cells and organs
Examples
Organ specific Autoimmune Diseases
  Hashimoto’s Thyroiditis
    Frequently seen in middle aged women
    X’terised by infiltration of thyroid gland by
     lymphocytes, macrophages and plasma cells
    The ensuing inflammatory response causes GOITER
     or visible enlargement of thyroid gland – a
     physiological response to hypothyroidism (decreased
     production of thyroid hormones
Hypothyroidism is caused when Abs are
 formed to a number of thyroid proteins
 including thyroglobulin and thyroid
 peroxidase – both involved in iodine uptake
Autoimmune hemolytic anaemia
 Systemic Autoimmune Diseases
Here the response is directed towards a broad
 range of targets and antigens and also
 involve a number of organs and tissues
  Systemic Lupus erythematosus (SLE)
    Appears in women b/n 20 and 40 years of age
    Ratio of females to males is 10:1
    X’terised by fever, weakness, arthritis, skin rashes
     and kidney desfunction
    It is more common in African American and Hisponic
     women than Caucasians
    Reasons?
Multiple sclerosis
  Attacks the CNS and causes neurological disabilities
  IT could be mild such as numbness in limbs or severe
   such as paralysis or loss of vision
  Genetic influence is important here
  Risk is higher in women than men 2 - 3X higher
Rhematoid arthritis
  Attacks the joints
  Most often common in women b/n the ages of 40 – 60
  Main effect being the inflammation of the joints
  But can also cause hemolytic, cardiavascular and
   respiratory systems
         Economic Importance
The social and financial burdens imposed
 by these chronic, debilitating diseases
 include:
  poor quality of life,
  high health care costs
  substantial loss of productivity
In addition, the majority of autoimmune
 diseases disproportionately affect women,
 Why are women more
susceptible than men to
    Autoimmunity?
    Reasons put forward so far includes;
Differences in Antibody production
   Females produces more Ab than males
   They also mount more vigorous immune response
    than males
Sex hormones also play important role
   Studies have shown that estrogen can stimulate auto-antibody
    production
      Demonstrated in SLE-prone mice
   Testosterone seems to be protective against several types of
    autoimmune diseases, eg.SLE, diabetes,MS etc
Ability of pregnant women to modify their
 immune system during pregnancy to keep the
 fetus
The presence of fetal cell in maternal circulation
 for decades – this can also lead to the
 development of autoimmune diseases
 Major research Areas
Causes of Autoimmune Diseases
The Burden of Autoimmune Diseases
Diagnosis, Treatment and Prevention
Training, Education and Information
POSSIBLE CAUSES Of Autoimmune diseases

Genetic, Environment, Infections etc
Recent reports have shown a marked association
 between 2-nonynoic acid, a cosmetic ingredient
 and primary biliary cirrhosis (PBC), a disease 9
 times more likely to occur in women.
Other suspected triggers of Autoimmune
 diseases include
   smoking,
   bacterial & retroviral proteins,
   hormone replacement therapy,
   use of nail polish.
 It’s thought that chemical degradation in the liver
 causes a loss of immune tolerance that
 predisposes Individuals to autoimmune diseases.
              Research In Ghana
 Study Conducted between 1983 and 1989 - 6yrs Period.
 Korle Bu Teaching Hospital
 They recorded 23 cases of Connective tissue disease
  during the period out of 4,507 admissions
 Age ranged from 26 – 63 yrs (mean = 44yrs)
 16 (70%) were females
 11 had SLE
 8 had R.A
    SLE 2.4 per thousand
    RA. 1.8 per thousand
 They then concluded that SLE and RA are NOT COMMON


                            Affram RK and Neequaye AR, (1991). Systemic Lupus
                            erythematosus and Other Rheumatic Disorders: Clinical
                            Experience in Accra:, Ghana Medical Journal Vol 25:299-302
         Other studies
SLE is most prevalent in women of
 African Origin – This has been
 demonstrated in a number of
 studies

                      1.   McCarthy et al 1995
                      2.   Symmons,1995,
                      3.   Houcgberg,1985,
                      4.   Siegel et al 1970
SLE IN AFRICANS
Population studies unavailable up to date
Most studies done are on case reports or
 series of reports of hospitalized patients.
Some of the countries in which these
 studies has taken place include:
  South Africa, Zimbabwe, Ghana, Nigeria,
   Guinea, Cote D’ voire, Gabon, DR Congo,
   Senegal
From all these published reports, SLE
 appears to be RARE in Africa
     SLE IN AFRICANS Cont’
Recent Studies from South and Central
 African suggest SLE to be increased in
 these regions whilst that in West African
 remain to be RARE
  This can be explained by the reporting
   BIAS
Treatment of Auto-immune Diseases
Current therapies include
  Treatment with immunosuppressive drugs
  Thymectomy and plasmapherisis for
   diseases involving immune complexes
  TNF alpha Blockers
      For controlling RA and Crohn’s disease


Treatment of human autoimmune
 diseases poses special challenges
         Challenges
Use of Immunosuppressive drugs does not leave
 the other immune system Intact
Immuno suppressive drugs such as:
  Corticosteriods,
  Azathioprine
  Crclophosphamide
are capable of depressing the immune response
 but also puts the patient at a greater risk of
 infection and development of cancers
Most current Therapies are not for cure but only
 reduces symptoms
THANK YOU
 FOR YOUR

ATTENTION!!