Malaria in Pregnancy & Anaemia in Pregnancy
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Transcript Malaria in Pregnancy & Anaemia in Pregnancy
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.
2.
3.
4.
McCarthy et al 1995
Symmons,1995,
Houcgberg,1985,
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!!