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$Unique_ID{BRK04282}
$Pretitle{}
$Title{Toxoplasmosis}
$Subject{Toxoplasmosis Lymphadenopathic Toxoplasmosis Disseminated
Toxoplasmosis }
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Copyright (C) 1986, 1987, 1988, 1989, 1993 National Organization for Rare
Disorders, Inc.

268:
Toxoplasmosis

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

Synonyms

DISORDER SUBDIVISIONS

     Lymphadenopathic Toxoplasmosis
     Disseminated Toxoplasmosis

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.


Toxoplasmosis is an infectious disease that can be caused by contact with
a microscopic parasitic organism called Toxoplasma gondii.  This parasitic
infection, found worldwide, can be either acquired or be present at birth
(congenital).  The congenital type is a result of a maternal infection during
pregnancy which is transmitted to the fetus, and involves lesions of the
central nervous system.  These lesions may lead to blindness, brain defects
and more serious conditions.  The disorder may be most severe when it is
transmitted to the fetus during the second through sixth month of pregnancy.
Twenty percent to 80% of those affected will show the presence of
toxoplasmosis antibodies when tested.

The acquired form includes these two types of Toxoplasmosis:
1) Lymphadenopathic Toxoplasmosis is a form of the disorder which
resembles mononucleosis.
2) Disseminated Toxoplasmosis is a form of the disorder in which lesions
involve chiefly the lungs, liver, heart, skin, muscle, brain, and spinal
chord membranes (meninges).  It is characterized by inflammation of the
lungs (pneumonitis), hepatitis, inflammation of the muscular walls of the
heart (myocarditis), and inflammation of the brain and meninges
(meningoencephalitis), all in varying degrees.

The prognosis for the acquired disease (when of moderate severity) is
usually good with treatment, and commonly subsides without complications.  If
untreated, this infection may persist for many months, and can cause
blindness.  It is rarely fatal in adults.

Symptoms

Symptoms of Toxoplasmosis may be severe, rapidly appearing, or there may be
no symptoms at all:

1) The more common mild form, which may resemble infectious
mononucleosis, is characterized by a disease of the lymph nodes in the neck
and armpit area (cervical and axillary lymphadenopathy), a vague feeling of
discomfort (malaise), muscle pain and irregular low fever.  Mild anemia,
hypotension, reduction of total white blood cells (leukopenia), elevation of
lymphoid white blood cell count (lymphocytosis), and slightly altered liver
function may also occur.  More commonly, it is a neck area lymph node
disorder involving no other obvious symptoms (asymptomatic cervical
lymphadenopathy).

2) In some cases the disorder may be an acute, suddenly occurring,
disseminated infection that affects primarily those people who seem to have a
reduced ability to fight infection.  This is usually characterized with a
rash, high fever, chills, and prostration.  Some patients may develop
inflammation of the lungs (pneumonitis), liver (hepatitis), muscular walls of
the heart (myocarditis), and possibly inflammation of the brain and possibly
meninges (meningoencephalitis).

3) Chronic toxoplasmosis, which causes severe inner eye inflammation
(retinochoroiditis or posterior uveitis), may be marked by muscular weakness,
weight loss, headache, and diarrhea.   Symptoms are usually vague and
indefinite making proper diagnosis difficult.

In some cases of toxoplasmosis, confusion and headaches may be the
primary symptoms.

In the neonatal congenital type of toxoplasmosis, features can be
variable.  Spontaneous abortion (miscarriage) may ensue if the infection
occurs early in pregnancy.  Infection later in pregnancy may result in
miscarriage or stillbirth, or in the birth of a living child with the
disease.

Symptoms of subacute toxoplasmosis infection may begin shortly after
birth, but more often appear months or several years later.  Central nervous
system (CNS) disorders such as hydrocephalus, microcephaly, intracranial
calcifications, and mental retardation may occur.  Skin rashes, enlargement
of the liver and spleen (hepatosplenomegaly), jaundice and inflammation of
the choroid and retina of the eye (chorioretinitis) may also be present.

Inflammation of the choroid and retina (chorioretinitis) usually
accompanies the congenital form and may occur in the acquired forms.  Chronic
disease with relapses can continue to occur in patients who survive the
subacute phase.  Abdominal organ (visceral) lesions, aside from those in the
liver, are unusual and tend to heal more readily than the central nervous
systems lesions.

Causes

Toxoplasmosis is an infectious disease which may be either congenital or
acquired.  Several modes of transmission may occur and must be guarded
against.  These include a parasite carried by birds and certain mammals,
notably cats, cattle, swine, sheep, rabbits, and dogs.  The disorder may also
be transmitted by consumption of under-cooked meat containing the parasitic
organisms (cysts), or by contact with cat feces containing the encapsulated
organisms (oocysts).  Care must be taken when cleaning the litter boxes of
infected cats as inadvertent hand-to-mouth contact with the parasite may
occur.  There is also evidence that the infection can be acquired through
inhalation of the dust arising when cleaning the litter.  However, with
proper hygienic precautions, infection is very unlikely.  Flies and/or
cockroaches may possibly transport the oocysts to human food.  In a human
host, the infection may possibly represent a reactivation of the latent
disease.

The congenital type of toxoplasmosis is due to the infection being
contracted during pregnancy and passed on to the fetus.  In particular,
contact with cats and cat feces during pregnancy must be avoided in
particular to control this occurrence.

Affected Population

Toxoplasmosis affects men and women in equal numbers world wide.  The
occurrence rate in infants is 0.25 - 5.0 per 100,000 live births.  This
disorder also may cause many abortions and still births in areas of the world
where the disorder may be more prevalent.

Approximately 40% of children with Toxoplasmosis become infected in the
womb because of maternal infection during pregnancy.  Of these children, 15%
have severe symptoms and 19% have mild symptoms.  Fetal damage is most likely
when the infection occurs during the second to the sixth month of gestation.
The majority of children born with Toxoplasmosis have no symptoms at birth,
but show evidence of damage several months to years later.  The most common
abnormalities are eye disease and low I.Q.  The estimated frequency of
Toxoplasmosis during pregnancy is 1.1 cases per 1,000 pregnant women.
However, maternal Toxoplasmosis acquired a month or longer before the
pregnancy is rarely transmitted to the fetus.

Related Disorders

Hepatitis is an infectious liver disorder which may be caused by exposure to
a large variety of infectious agents or substances.  Which type of hepatitis
a patient may have is usually determined by the cause.  When hepatitis is
caused by toxoplasmosis, the liver and spleen are usually involved.  (For
more information on this disorder, choose "Hepatitis" as your search term in
the Rare Disease Database.)

Encephalitis encompasses a large group of viral infections of the brain
with a variety of neurological symptoms which depend on the infectious agent.
Encephalitis in conjunction with toxoplasmosis appears to be transmitted by
the same carrier.

Therapies:  Standard

Acute Toxoplasmosis of newborns, pregnant women, and patients who have had
their immune response diminished should be treated with antibiotics such as
trisulfapyrimidines or sulfadiazine, plus pyrimethamine for three to four
weeks.  The toxicity of pyrimethamine can be minimized with the daily
administration of folinic acid.  Since pyrimethamine can produce deformities
in animal fetuses, sulfonamides alone should be used in pregnant women who
are treated for toxoplasmosis.

Some patients with Toxoplasmosis do not require specific therapy unless a
vital organ such as the eyes, brain, or heart is involved, or if other
symptoms are severe and persistent.  Corticosteroids are often useful in
these situations to control inflammation.  Periodic blood counts may be
obtained during therapy to monitor the toxicity of drugs used for treatment
of this disorder.

Since sulfadiazine is no longer manufactured in the United States,
patients can receive the drug through the Centers for Disease Control (CDC).
To request sulfadiazine, contact CDC's Division of Parasitic Diseases,
National Center for Infectious Diseases, [phone].

Therapies:  Investigational

The Food and Drug Administration (FDA) has awarded a research grant to Rima
McLeod, M.D., Michael Reese Hospital & Medical Center, Chicago, IL, for
comparison studies on treatments for congenital Toxoplasmosis.  Included in
the studies are the experimental drugs pyrimethanine sulfadiazine,
spiramycin, and pyrimethamin sulfadoxine.

Research on Toxoplasmosis is ongoing in many parts of the world.  For
information on the latest developments in this research, please contact:

     Centers for Disease Control
     1600 Clifton Rd. NE
     Atlanta, GA  30333.
     [phone]

For information on additional therapies that have been designated as
Orphan Drugs in the last few months, please return to the main menu of NORD
Services and access the Orphan Drug Database.

This disease entry is based upon medical information available through
April 1993.  Since NORD's resources are limited, it is not possible to keep
every entry in the Rare Disease Database completely current and accurate.
Please check with the agencies listed in the Resources section for the most
current information about this disorder.

Resources

For more information on Toxoplasmosis, please contact:

     National Organization for Rare Disorders (NORD)
     P.O. Box 8923
     New Fairfield, CT  06812-1783
     [phone]

     Toxoplasmosis Interest Group
     52 Edgell Street
     Gardner, Mass.  01440
     [phone]

     Centers for Disease Control (CDC)
     1600 Clifton Road, NE
     Atlanta, GA  30333
     [phone]

     NIH/National Institute of Allergy and Infectious Diseases
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]

References

MERCK MANUAL OF DIAGNOSIS AND THERAPY:  Robert Berkow, et al., eds; Merck
Sharp & Dohme Research Laboratories, 1982.  P. 24.