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$Unique_ID{BRK02992}
$Pretitle{}
$Title{AIDS (Acquired Immune Deficiency Syndrome, part I)}
$Subject{AIDS (Acquired Immune Deficiency Syndrome) AIDS DISORDER SUBDIVISIONS
AIDS AIDS related complex, also known as ARC, AIDS prodrome, Wasting/Lymph
Node Syndrome, and Mini-AIDS}
$Volume{}
$Log{}

Copyright (C) 1986, 1987, 1990, 1991, 1992, 1993 National Organization
for Rare Disorders, Inc.

78:
AIDS (Acquired Immune Deficiency Syndrome), part I


** IMPORTANT **
It is possible that the main title of the article (Acquired Immune
Deficiency Syndrome) is not the name you expected.  Please check the SYNONYMS
listing to find the alternate names and disorder subdivisions covered by this
article.

Synonyms

     AIDS

DISORDER SUBDIVISIONS

     AIDS
     AIDS related complex, also known as ARC, AIDS prodrome, Wasting/Lymph
Node Syndrome, and Mini-AIDS

General Discussion

** REMINDER **
The information contained in the Rare Disease Database is provided for
educational purposes only.  It should not be used for diagnostic or treatment
purposes.  If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.


In the acquired immune deficiency syndrome (AIDS) the body's ability to
ward off infection progressively deteriorates.  Organisms which in a healthy
person would either fail to cause disease, cause mild disease, or at least
provoke immunity, completely overwhelm the AIDS patient.  Patients with
severe AIDS also contract various uncommon, life threatening infections,
particularly pneumocystis carinii pneumonia, and have an unusually high
incidence of a rare cancer, Kaposi's sarcoma.  Individuals in the early
stages of the disease are unusually susceptible to many milder infections.

Symptoms

AIDS may be preceded by a period of asymptomatic immune abnormalities, or by
a prodromal state lasting as long as 36 months.  This "AIDS related complex"
is characterized by otherwise unexplained lymphadenopathy (swelling and
disease of lymph nodes) for a period of at least three months, recurrent flu-
like symptoms, fatigue and malaise, loss of weight or appetite, fever, night
sweats, unexplained diarrhea, or diarrhea due to amebiasis, idiopathic
thrombocytopenic purpura in some cases, and an unusual susceptibility to mild
infections.  Commonly, infections are by yeasts such as oral thrush, by
amoebas, fungi, viruses such as Herpes Zoster and molluscum contagiosum, and
staphylococcus bacteria, leading to purulent skin infections.

Researchers now believe the AIDS virus may be present in a patient as
much as 5 to 7 years before symptoms appear.  In 1988, scientists at the
federal Centers for Disease Control (CDC) in Atlanta, GA, reported many
individuals infected with the AIDS virus show a sharp increase in virus-
infected white blood cells in the year before these patients develop the full
blown disease.  A decrease of one type of disease-fighting white blood cells
known as T-4 helper cells also occurs as the infection progresses.  Other
studies have suggested that increases in chemicals in the blood signaling
viral reproduction might serve as clues to early diagnosis of AIDS in
susceptible patients.

Full blown AIDS continues to manifest fever, wasting, lymphadenopathy,
and susceptibility to infections.  The infections become much more severe,
however, and are often due to uncommon organisms.  They may be difficult to
treat, and if treated successfully, may still recur repeatedly.  Several
infections often coexist.  A particularly serious threat is infection by the
protozoan pneumocystis carinii.  Serious infections may also be viral,
bacterial, or fungal.  See table below.

VIRAL INFECTIONS:
     Cytomegalovirus
     Herpes simplex virus types I and II
     Epstein-Barr virus (normally associated with mononucleosis)
     Varicella-Zoster (normally associated with Chicken Pox)
     Papova virus

BACTERIAL INFECTIONS:
     Mycobacterium tuberculosis (the organism causing tuberculosis)
     Mycobacterium avium-intracellulare
     Legionella pneumophilus (the organism causing Legionnaire's disease)
     Klebsiella pneumonae

FUNGAL INFECTIONS
     Candida albicans (yeast infection)
     Cryptococcus neoformans
     Aspergillus species
     Histoplasma capsulata

PROTOZOAN INFECTIONS:
     Pneumocystis carinii
     Toxoplasma gondii
     Entamoeba histolytica ("amoebas")
     Giardia lamblia (causes diarrhea)
     Cryptosporidium
     Isopora bellii

Pneumonias, central nervous system infections, involvement of the eyes,
particularly the retina, gastrointestinal symptoms (especially persistent
diarrhea) and general wasting, fever, and weakness may be one or more of
these organisms.  Often diagnosis is difficult because symptoms and signs of
the infections in the immunosuppressed patient differ from those in
immunologically normal individuals.

Malignant neoplasms are also characteristic of AIDS.  Kaposi's sarcoma is
especially common, occurring in as many as 37% of the patients.  In this type
of cancer, the skin and often the viscera are covered with small brown
plaques and nodules representing vascular tumors.  Patients who have only
Kaposi's Sarcoma have a somewhat better prognosis than those with
opportunistic infections, apparently because their immune systems retain
slightly better function.  Other cancers associated with AIDS include certain
malignant undifferentiated and differentiated lymphomas, such as Hodgkin's
disease, and carcinomas of certain cells of the tongue and rectum.

Another feature of AIDS is a decrease in the total number of lymphocytes
(cells responsible for immunity) in the blood.  An absence of allergic skin
reactions and abnormalities in the relative numbers and functioning of the
different kinds of lymphocytes in the circulation also indicate cellular
immunodeficiency.  Evidence of exposure to the causative virus and abnormal
proportions of the different lymphocyte types has been found in many members
of the groups at risk for AIDS.  Clearly, not all these people develop the
disease.

Recent research suggests that as many as 60% of AIDS patients may develop
dementia.  The dementia may occur at any age.  According to the National
Institute of Neurological Disorders and Stroke, as the number of patients
affected by the AIDS retrovirus continues to grow, the associated
neurological syndromes are recognized with increasing frequency.
Neurological involvement may be apparent before severe immunodeficiency is
recognized.

Dementia is one of the more common and devastating neurological
complications of AIDS.  As many as 60 percent of patients with AIDS may
develop dementia that cannot be attributed to opportunistic infections.  The
dementia may occur at any stage; it is often manifested very early in the
clinical course of the illness.  Some of these patients also develop spastic
paraplegia and ataxia associated with vacuolar changes in the myelin of the
spinal cord.

Infection with the AIDS retrovirus is also associated with the
development of peripheral nerve disease in a lesser number of patients.
Although neuropathy may affect 10 percent or more of patients with AIDS, the
clinical and pathological features are not completely characterized.  The
spectrum of symptom complexes includes sensory and motor neuropathies and
multiple mononeuropathy.

Developmental abnormalities in children with AIDS, characterized by loss
of cognitive ability and progressive long-tract signs, are now encountered
with increasing frequency.  An AIDS-associated dysmorphic syndrome in
children due to intrauterine infection has also been described.

Researchers have found that the drug DHPG (dihdroxypropoxymethyl guanine)
is effective against cytomegalovirus retinitis in AIDS patients.  The
patient's eye sight often can be protected by this treatment.

For more information on AIDS, see the articles in the AIDS Update section
of NORD Services.

Causes

AIDS is caused by a Human T-cell Leukemia Virus, known as HIV or human
immunodeficiency virus (previously the virus was referred to as HTLV-III).
Its transmission is not well understood, but is probably via the introduction
into the body of fluids from an infected person, i.e. via blood transfusions
(rare), sharing of contaminated needles, and intimate sexual contact, but
apparently not via saliva.  About 55% of the homosexual population in certain
communities have been found to have antibodies to HIV, suggesting that,
although exposure to it has been widespread, some other cofactors may be
necessary for AIDS or its prodrome to develop.  Possible cofactors include
genetic predisposition and coinfection by cytomegalovirus or Epstein-Barr
virus.  These viruses are also linked with many of the cancers associated
with AIDS.  Cytomegalovirus, for example, is suspected to be responsible for
Kaposi's sarcoma.

Kaposi's sarcoma, immunologic evidence of exposure or infection with HIV,
and AIDS-like syndromes are exceptionally common among both sexes in central
Africa, and it has been suggested that the disease originated there.

At an October, 1986, AIDS conference at Montefiore Medical Center in New
York, researchers reported the proportion of American AIDS cases clearly
traced to heterosexual intercourse is two percent, up from one percent in
earlier years of the epidemic.  Intravenous drug addicts and their sex
partners are the primary sources of AIDS infection among heterosexuals.  Four
out of five cases reported among this group are women.  Among immigrant cases
in this country, the proportion attributed to heterosexual contact is four
percent.  Three percent of cases seem to have no explained cause, but there
are questions as to accurate admission by these patients of past drug use
and/or sexual practices.

In New York City, as of Sept. 15, 1986, only two percent of AIDS cases
were attributed to heterosexual contact.  Eighty percent of these patients
are black or Hispanic.

Data from blood donors screened from April through December, 1985 in New
York City revealed 0.08 percent had antibodies to the AIDS virus, a sign of
infection.  Further investigation revealed that ninety percent of those with
the virus had homosexual or drug experience, or a sex partner who did.  In
only eleven cases, could the source of infection not be identified.

In tests of military applicants in New York City from October, 1985
through July 1986, 1.06 percent of men and 0.83 percent of women had evidence
of AIDS infection.  Most of these infections could be traced to homosexual
contact or drug use and the proportion attributed to heterosexual relations
was "minor."

Growing statistics support the conclusion of some researchers that the
passage of the AIDS virus from female to male during intercourse is extremely
rare.

However, two new studies on risks of unprotected intercourse with a virus
carrier have raised some puzzling questions.  One study found that half or
more of steady, long-term heterosexual partners of AIDS patients with no
other possible exposure, were also infected.  The virus seemed to pass as
readily from women to men as the reverse, and ordinary vaginal intercourse
was a sufficient means.

Sixteen AIDS patients in one of these studies continued to have
unprotected intercourse from one to three years.  Thirteen of their partners
became infected, for a transmission rate of over eighty percent.  Of twelve
AIDS patients and their partners who continued having sex but used condoms,
the infection spread in only two cases.  This low rate of transmission seems
disturbing given the presumed safety of condoms.  In both of the latter
cases, the virus spread from man to woman.  Oral sex involving semen
discharges might be to blame.

Some studies find inconsistent rates of sexual spread of the AIDS virus
depending on how the first partner became infected.  The virus was passed
through intercourse far more readily from drug abusers than from people
exposed by contaminated blood products in one study.  Another study indicated
that rates of infection may vary among individuals or in the same person over
time.

Available evidence indicates that the likelihood of viral transmission in
a single heterosexual encounter is "less than one percent."  Scientists
suspect that the virus spreads more easily in anal intercourse, which more
often involves tearing of tissue that would aid the entry of the virus into
the bloodstream.  For anyone having sex with multiple partners, the danger of
infection with the AIDS virus is rising dramatically.

Recent evidence suggests that the AIDS virus can live in insect hosts
such as mosquitoes and other blood-sucking insects.  However, there is no
evidence that these insects can transfer the virus to humans.  To date, no
case of AIDS has been linked to an insect bite in the United States.

Affected Population

AIDS is now known to be caused by a virus.  As of December, 1991, the CDC
reported that approximately one million Americans are infected with the AIDS
virus; 206,392 cases of AIDS have been diagnosed and 133,232 deaths from AIDS
have occurred in the United States.  The population at highest risk for AIDS
comprises homosexual or bisexual males.  Other high risk populations include
past or present intravenous drug abusers, blood transfusion or blood product
recipients, including hemophiliacs, female sexual partners of bisexual males
or IV drug abusers, or women who themselves are IV drug abusers, and children
whose parents are in one of the other risk groups.  Most cases have occurred
in the United States, but several hundred cases have been reported from
Europe, the Caribbean, and Africa.  Although there is a high incidence of
AIDS in Haiti, Haitians in United States are no longer considered to be a
risk category of individuals.  It is possible that the disease originated in
central Africa.

NOTES FROM NORD

According to the Centers for Disease Control (CDC), 980 children have
been diagnosed with AIDS as of May 1988.  Some of these acquired the disease
in the womb from infected mothers, and some contracted the disease from blood
transfusions before the AIDS blood screening program was initiated in 1985.
A recent study of 20 children who contracted the AIDS virus through
transfusions before 1985 indicated that one-third of the children have died
or are ill with AIDS, one-third show no sign of the illness, and one-third
have more than the usual number of childhood infectious diseases but their
health is within the normal range of children their age.  This data compares
to adults with the AIDS virus; one-third of carriers have died or are ill
with AIDS five to six years after infection.

A pregnant woman with AIDS always passes the AIDS antibodies to her
fetus, but she only passes the actual virus to the baby forth percent of the
time.  When the babies become fifteen months old, they start making their own
antibodies if the virus is present.

There is no way to predict which babies of infected mothers will get the
AIDS virus.  To date, sixty percent of children born to mothers with AIDS
antibodies show no sign of infection.

Acquired Immune Deficiency Syndrome can no longer be regarded as a
disease restricted to certain populations.  However, major cities seem to
have higher numbers of reported cases.  Nationally, 4 in 10,000 persons are
affected, with thirteen men to one woman contracting this disorder.  In
Manhattan (New York City), there are 200 cases for every 10,000 persons.
These statistics are based on data from blood banks.  The uninfected partner
of a person with AIDS will have a forty to fifty percent chance of contacting
the disease.

Therapies:  Standard

The treatment of choice for AIDS (Acquired Immune Deficiency Syndrome) is the
Orphan Drug Zidovudine, Brand name Retrovir (formerly known as azidothymidine
or AZT).  The drug appears to halt the progression of AIDS (and in some cases
allows the immune system to rebuild itself) by inhibiting production of an
essential enzyme that is necessary for the AIDS virus to reproduce itself.
(A $30 million emergency fund to help low-income AIDS patients buy AZT, has
been established by the Health Resources and Services Administration.
Eligibility will be determined by states; for more information, call (800)
843-9388).  In 1990, AZT was approved by the FDA in treating pediatric AIDS
patients as young as six months old.  The drug was approved in 1987 for
patients 13 years of age and older.  The combination therapy of AZT
(Retrovir) with Hoffman LaRoche's HIVID (DDC) has been approved by the FDA.
This combination therapy is more effective than AZT alone.

The primary treatment for AIDS is prevention.  Use of condoms and changes
in sexual behavior are recommended.  Promiscuous sex may increase the
likelihood of contracting AIDS.

Many of the infections associated with AIDS respond to antibiotic,
antifungal, etc., treatment, although recurrences are very common.  Nystatin,
clotrimazole, and ketoconazole have controlled episodes of esophageal and
oral candidiasis.  In this fungal infection as well as in cryptococcal
meningitis, amphotericin-B has been useful.  Herpes simplex has responded to
a course of treatment with acyclovir.  Toxoplasmosis may be controlled in
some cases with sulfadiazine or pyrimethamine, although these drugs have
immunosuppressive effects and thus may render the patient more vulnerable
than ever to opportunistic infections.  Cryptosporidiosis may be treated
symptomatically with tincture of opium, diphenoxylate, or cholestyramine;
spiramycin, an antibiotic used in Canada and Europe, but not yet approved in
the United States, appears to resolve or diminish diarrhea associated with
cryptosporidiosis.  (See below for manufacturer of spiramycin.)  A
combination of quinine and clindamycin has also been reported effective.

Pneumocystis carinii pneumonia is more difficult to treat.  At present,
trimethoprim-sulfamethoxazole co-trimoxazole, Dapsone and pentamidine are the
three drugs known to be effective.  Pentamidine isethionate (Pentam 300), an
orphan drug, is commercially available in the United States.  For further
information on this drug, contact:  LyphoMed, Inc., 2020 Ruby Street, Melrose
Park, IL 60610.

However, researchers have recently published scientific information
indicating that about one-third of AIDS patients who were treated with
pentamidine were likely to develop a serious form of chronic low blood sugar
(hypoglycemia).  When using pentamidine to treat Pneumocystis Carinii in AIDS
patients, physicians are advised to check glucose levels daily and creatinine
every other day during and after (for several days) pentamidine therapy.  The
drug should be given in a hospital setting where patients can be carefully
monitored.

No treatment has been found for some kinds of AIDS related infections.
These include Mycobacterium avium intracellulare, cytomegalovirus, and
Epstein-Barr virus.

Kaposi's sarcoma, as well as other neoplasms occurring in AIDS, respond
to chemotherapy.  Drugs have included vinblastine, etoposide, doxorubicine,
bleomycin, and combinations of these.  Interferon in high doses, which does
not seem to be useful in treating the underlying disorder or opportunistic
infections, does appear to be effective in treating Kaposi's sarcoma.  Also
reportedly effective in this cancer is vincristine; this drug has antitumor
activity without causing further immunosuppression due to bone marrow
suppression.

The National Institutes of Health are supporting studies to determine the
effectiveness of suramin, a drug usually used as an antiparasitic, in
inhibiting the virus' replication and capacity to damage immune cells.
Treatment with interleukin II to promote T-lymphocyte growth, and with
various types of interferon, an antiviral protein, have not been effective;
nor has treatment with acyclovir, vidarabine, various other drugs, white cell
transfusions, thymic factors, and thymus and bone marrow transplants.

Among the precautions against contracting or spreading AIDS recommended
by the Public Health Service are the following:

     1) Sexual contact with persons known or suspected to have AIDS should be
avoided.  Multiple sex partners increase the probability of developing the
disease.
     2) No members of high risk groups should donate blood or blood products.
     3) Blood transfusions should only be performed when absolutely necessary.
     4) Screening procedures for plasma or blood likely to transmit AIDS have
been developed, and safer blood products for hemophilia patients.
     5) Health care personnel, laboratory workers, and others in frequent
contact with AIDS patients should take great care to avoid wounds from
contaminated needles and similar sharp objects, and contact with blood soiled
materials.

A new drug for the treatment of Candidiasis, Crytococcal Meningitis, and
other persons with weakened immune systems such as AIDS patients has recently
been approved by the FDA.  The drug, diflucan (fluconazole), has been found
effective against these types of infections in persons with depressed immune
systems.

The Food and Drug Administration has approved the antiviral drug
didanosine (DDI) for treatment of adults and children with advanced AIDS who
cannot tolerate or are not helped by AZT.  DDI can cause pancreatitis in
patients with AIDS.  Pancreatitis is a potentially fatal inflammation of the
pancreas.  Patients taking DDI should avoid alcoholic beverages and seek
medical help immediately if they have abdominal pain, nausea, or vomiting.
As of March 13, 1990, of the 8,300 AIDS patients taking DDI, 78 developed
pancreatitis and seven of them died.