TOXOPLASMOSISTOXOPLASMOSIS

Developed by Developed by

Pam Holmes, Christy Stalcup, and Pam Holmes, Christy Stalcup, and Pam YarboroughPam Yarborough

WHAT IS TOXOPLASMOSIS? WHAT IS TOXOPLASMOSIS?

Toxoplasmosis is an infection caused by a parasite most Toxoplasmosis is an infection caused by a parasite most often found in cats and farm animals. Humans can catch often found in cats and farm animals. Humans can catch this disease from:this disease from:

coming into contact with infected cat fecescoming into contact with infected cat feceseating raw or undercooked meat that’s infected eating raw or undercooked meat that’s infected eating contaminated vegetables or fruitseating contaminated vegetables or fruitsbeing born with it being born with it

Note: Once a person is infected, the infection remains in Note: Once a person is infected, the infection remains in the body for life, usually in an inactive form. It can the body for life, usually in an inactive form. It can reactivate when that person’s immune system is weak. reactivate when that person’s immune system is weak.

About 98% of cases of Toxoplasmosis are About 98% of cases of Toxoplasmosis are acquired through Congenital Toxoplasmosis. acquired through Congenital Toxoplasmosis.

One study showed that 76% of infants infected with congenital toxoplasmosis had ocular lesions, 51% had neurological involvement, and 26% had either hydrocephalus (increased intracranial pressure) or michrocephaly (small brain). It is evident that vision problems are very common with Congenital Toxoplasmosis.

Once the mother develops immunity to the organism, all future pregnancies are protected from transmission of the organism.

Signs and Symptoms Signs and Symptoms

1. Toxoplasmosis in an 1. Toxoplasmosis in an otherwise healthy personotherwise healthy person may have no symptoms or only a few swollen may have no symptoms or only a few swollen glands usually in the patient’s neck. glands usually in the patient’s neck.

2. Toxoplasmosis in a person with a 2. Toxoplasmosis in a person with a weakenedweakened immune systemimmune system may only have symptoms of may only have symptoms of swollen glands, or in the case of an infection swollen glands, or in the case of an infection that attacks the brain and nervous system, the that attacks the brain and nervous system, the symptoms may include fever, seizures, symptoms may include fever, seizures, headache, psychosis, and problems with vision, headache, psychosis, and problems with vision, speech, movement, or thinking.speech, movement, or thinking.

3. Children 3. Children born with Toxoplasmosisborn with Toxoplasmosis, which accounts for , which accounts for about 98% of cases, may show symptoms including: about 98% of cases, may show symptoms including:

FeverFever Swollen glandsSwollen glands Jaundice Jaundice An unusually large or small headAn unusually large or small head RashRash Bruises or bleeding under the skin Bruises or bleeding under the skin Anemia Anemia Enlarged liver or spleenEnlarged liver or spleen SeizuresSeizures Limp muscle toneLimp muscle tone Mental retardation Mental retardation Hearing lossHearing loss Vision problems (toxoplasmosis of the eye)Vision problems (toxoplasmosis of the eye)

Toxoplasmosis of the Eye Toxoplasmosis of the Eye

Congenital Toxoplasmosis is the Congenital Toxoplasmosis is the most commonmost common form. If the form. If the mother acquires the infection mother acquires the infection during the first trimester, 17% during the first trimester, 17% of these babies develop of these babies develop congenital toxoplasmosis and congenital toxoplasmosis and the effects are severe. the effects are severe. However, if the infection However, if the infection occurs during the third occurs during the third trimester, 65% of the babies trimester, 65% of the babies develop the disease. Yet, the develop the disease. Yet, the infant usually has no infant usually has no symptoms. symptoms.

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DAMAGE TO THE EYEDAMAGE TO THE EYEThe parasite usually invades the retina and the choroid tissue. The parasite usually invades the retina and the choroid tissue.

Depending upon the area and severity of the infection, visual Depending upon the area and severity of the infection, visual acuity can be unaffected to severely affected. The retina is acuity can be unaffected to severely affected. The retina is inflamed by the infection and sometimes when the inflammation inflamed by the infection and sometimes when the inflammation settles, scars are left on the retina. Symptoms include floaters settles, scars are left on the retina. Symptoms include floaters and blurred vision. If the scarring is on the central macula, and blurred vision. If the scarring is on the central macula, detailed vision will be affected. Approximately 35% of all detailed vision will be affected. Approximately 35% of all retinachoroiditis cases can be attributed to toxoplasmosis.retinachoroiditis cases can be attributed to toxoplasmosis.

Active Toxoplasmosis Inactive Toxoplasmosis ScarActive Toxoplasmosis Inactive Toxoplasmosis Scar

                                                             

Effects of Ocular ToxoplasmosisEffects of Ocular Toxoplasmosis

Common Effects: Common Effects:

Inflammation of retinaInflammation of retina Blurred vision Blurred vision FloatersFloaters NystagmusNystagmus AmblyopiaAmblyopia Squint Squint

Occasional Effects: Occasional Effects:

CataractsCataracts The eye can be smallThe eye can be small Optic atrophy Optic atrophy Cerebral visual Cerebral visual

impairmentimpairment

Functional ImplicationsFunctional Implications

Functional implications vary depending on severity of Functional implications vary depending on severity of infection and/or scaring and how successful the infection and/or scaring and how successful the

treatment. Those affected often describe vision as treatment. Those affected often describe vision as “hazy” with floaters. Some implications are more “hazy” with floaters. Some implications are more

serious such as total blindness in one or both eyes. serious such as total blindness in one or both eyes. Those affected early during pregnancy often suffer Those affected early during pregnancy often suffer other implications such as mild to severe mental other implications such as mild to severe mental

retardation, cerebral palsy, seizures and other retardation, cerebral palsy, seizures and other problems. Appropriate accommodations and problems. Appropriate accommodations and

modifications should be determined by the FVE.modifications should be determined by the FVE.

TreatmentTreatment

Treatment will not result in the elimination of the Treatment will not result in the elimination of the organism from the eye. Since new lesions can organism from the eye. Since new lesions can form if the organism reactivates, especially form if the organism reactivates, especially during adolescence, patients should be closely during adolescence, patients should be closely monitored.monitored.

Medications: Medications: Spiramycin during pregnancy Spiramycin during pregnancy Antibiotics and steroid tablets during an infectionAntibiotics and steroid tablets during an infection Pyrimethamine/sulphadoxine for 6-12 months as Pyrimethamine/sulphadoxine for 6-12 months as

follow-up procedurefollow-up procedure

SamSamHistory

Sam is a third grader that was diagnosed with Toxoplasmosis (visual impairment), mental retardation, and other health impairment. He suffered acute retino-choroidal inflammation which produced dense scaring in both eyes. He has suffered reactivations which caused adjacent scars creating satellite lesions to the macula in the right eye. His eye report states that there is significant scar tissue stretching from the nasal passage to the optic nerve. There is little medical information other than eye examination reports. It was determined in ARD meeting that there was little (if any) pre-natal care and treatment of the toxoplasmosis after birth. It is a continuing problem to get consent signed to obtain medical records from the parents.

Environment

Sam is attending third grade in an inclusive classroom environment. He functions about 2 ½ years below grade level. It is difficult to determine if it is visual deficits or cognitive ability that hinders learning. Some modifications in the classroom are 36 pt font, one step directions, peer tutoring, slant board, frequent breaks, well lit environment, auditory instruction coupled with visual input, clear/uncluttered copies, contrast, allow positioning for materials as needed, do not ask questions like “can you see this” have him tell you what he sees, do not place him beyond 6-8 feet from board, make sure he is wearing glasses at all times and watch for signs such at fatigue and headaches.

SourcesSources

http://www.nlm.nih.gov/medlineplus/ency/imagepages/1http://www.nlm.nih.gov/medlineplus/ency/imagepages/17186.htm7186.htm

http://www.eyemdlink.com/Condition.asp?http://www.eyemdlink.com/Condition.asp?ConditionID=444ConditionID=444

http://www.patient.co.uk/showdoc/40000376/http://www.patient.co.uk/showdoc/40000376/

www.viscotland.org.ukwww.viscotland.org.uk

http://www.kidshealth.org/PagManager.jsp?http://www.kidshealth.org/PagManager.jsp?dn=KidsHealth&lic=1&ps-107&cat_id=20045&art......dn=KidsHealth&lic=1&ps-107&cat_id=20045&art......

http://www.revoptom.com/handbook/sect5i.htmhttp://www.revoptom.com/handbook/sect5i.htm

Program in Low Vision Therapy, Region 4 Education Program in Low Vision Therapy, Region 4 Education Service Center, McKinney, Bill, Ph.D. Executive Service Center, McKinney, Bill, Ph.D. Executive Director, 2004. Houston, Tx pg 25Director, 2004. Houston, Tx pg 25