Clinical Presentation

The signs and symptoms of congenital toxoplasmosis exhibit a wide range of severity. Common manifestations include:

• Preterm birth: Birth occurring earlier than the expected due date, estimated in approximately half of affected infants.

• Low birth weight: Infants weighing less than expected for their gestational age at birth.

• Ocular Impairment: Visual disturbances such as blurred vision, heightened sensitivity to light (photophobia), and excessive tearing (epiphora).

• Intrauterine growth restriction (IUGR): Reduced fetal growth rate within the uterus compared to normal expectations.

• Mild Fever: A slightly elevated body temperature.

• Vomiting episodes: Frequent episodes of throwing up.

• Jaundice: Yellowish discoloration of the skin and sclera (whites of the eyes) due to liver involvement.

• Diarrhea: Loose and frequent bowel movements.

• Anemia: Reduced levels of red blood cells in the blood.

• Auditory impairment: Hearing loss resulting from damage to the auditory system.

• Delayed motor and cognitive development: Slower achievement of developmental milestones and difficulties with movement skills.

• Hydrocephalus: Accumulation of cerebrospinal fluid in the brain’s ventricles, leading to increased head circumference.

• Feeding difficulties: Problems with sucking or swallowing.

• Lymphadenopathy: Swollen lymph nodes, often painless, firm, and localized.

• Hepatosplenomegaly: Enlargement of the liver and spleen.

• Macrocephaly: Abnormally large head size.

• Microcephaly: Abnormally small head size.

• Skin Rash: A typical rash characterized as flat with small raised areas (maculopapular), often sparing the palms and soles.

• Bulging fontanelle: Protrusion or swelling of the soft spot on an infant’s head.

• Abnormal Muscle Tone: Muscles that are either excessively stiff or overly relaxed.

• Seizures: Episodes of uncontrolled electrical activity in the brain, causing convulsions.

• Intracranial Calcifications: Calcium deposits within the brain tissue, indicating areas of parasitic damage.

Diagnosis of Toxoplasmosis

Diagnosis of congenital toxoplasmosis typically involves a combination of:

• Patient History: Gathering details about the mother’s pregnancy, potential exposure risks, and the infant’s symptoms.

• Physical Exam: A thorough physical assessment of the newborn.

• Laboratory and Imaging Studies: Various tests to confirm the diagnosis.

  • Serology: Blood tests measuring antibody levels. Elevated Immunoglobulin G (IgG) suggests past infection. Immunoglobulin M (IgM) testing helps determine recent infection, crucial for assessing fetal risk during pregnancy.

  • Culture: Attempting to grow the parasite in a lab from tissue samples like cerebrospinal fluid. Less common due to sampling difficulty.

  • Amniocentesis: Testing amniotic fluid for the parasite’s DNA in pregnant women.

  • Brain Biopsy: Rarely performed in non-responsive cases to detect toxoplasmosis cysts.

  • Liver Function Tests (LFTs): Blood tests assessing liver enzymes (ALT, AST) for liver involvement.

  • Complete Blood Count (CBC): May reveal eosinophilia (elevated eosinophils, a type of white blood cell).

  • Renal Function Tests (RFTs): Blood tests assessing urea and creatinine levels for kidney involvement.

  • Electrolyte Levels: Blood tests to check for imbalances in electrolytes like potassium, calcium, and sodium.

• Imaging Studies: To evaluate disease extent:

  • Ultrasound: Used during pregnancy to visualize the fetal brain for hydrocephalus. May also detect hepatosplenomegaly or liver calcifications in fetuses around 20-24 weeks gestation.

  • Magnetic Resonance Imaging (MRI): Detailed brain images for suspected nervous system involvement.

  • Computed Tomography (CT) Scan: Brain scan to identify intracranial calcifications, ventriculomegaly (enlarged ventricles), and hydrocephalus.

Treatment and Management

Toxoplasmosis treatment strategies are guided by the patient’s immune status and infection severity.

• Outpatient Management: Typically suitable for immunocompetent patients or those without significant organ damage.

• Activity Restriction: May be advised depending on illness severity and affected organ systems.

• Patient Education: Essential, especially for pregnant women, focusing on prevention and fetal risks.

• Regular Follow-up: Typically bi-weekly until stabilization, then monthly during therapy.

• Routine Blood Monitoring: Weekly CBC for the first month, then bi-weekly; monthly LFTs and RFTs.

• Medications:

  • Pyrimethamine: Antimalarial drug, inhibits folic acid absorption in the parasite.

  • Sulfadiazine: Antibacterial, often combined with pyrimethamine for effective toxoplasmosis treatment, targeting the tachyzoite stage. Renal excretion requires dosage adjustment in kidney impairment. Avoid in G6PD deficiency due to hemolysis risk; clindamycin is an alternative.

    • Sulfadiazine Dosage: 1-1.5 grams four times daily (QID) for 3-4 weeks, or 100 mg/kg/day divided twice daily (2DD).

  • Pyrimethamine: High doses can cause hemolytic anemia, necessitating close monitoring.

    • Pyrimethamine Dosage: 50-75 mg once daily orally (OD PO) for 2-3 weeks, then reduced to 25-37.5 mg OD PO for 4-5 weeks.

  • Corticosteroids: Prednisolone (1 mg/kg/day) used when cerebrospinal fluid protein is elevated or vision is threatened by chorioretinitis, continued until resolution.

  • Trimethoprim/Sulfamethoxazole: Antibiotic combination, 40 mg/kg/day divided twice daily (2DD).

  • Dapsone (with Pyrimethamine): 100 mg/kg/day orally for 1-3 weeks.

  • Clindamycin (with Pyrimethamine): For sulfadiazine sensitivity, 10-12 mg/kg twice daily orally for 4 weeks.

  • Folic Acid: Vitamin supplementation to mitigate bone marrow suppression from pyrimethamine.

    • Folic Acid Dosage: 10 mg three times weekly.

Prevention

Preventing toxoplasmosis is critical, especially for pregnant women and immunocompromised individuals. Key measures include:

• Avoidance of Undercooked Foods: Refrain from consuming raw or undercooked meat, unpasteurized milk, and raw eggs.

• Hygiene After Raw Food Handling: Thoroughly wash hands after handling raw meat, gardening, or soil contact.

• Cat Feces Precautions: Avoid contact with cat feces.

• Litter Box Disinfection: Disinfect cat litter boxes with boiling water for at least 5 minutes.

• Safe Cooking Temperatures: Cook food to recommended safe internal temperatures.

• Fruit and Vegetable Washing: Wash and peel all fruits and vegetables before eating.

• Frequent Handwashing: Wash hands often, especially after food handling, and clean meat/produce cutting boards.

• Gardening Gloves: Wear gloves when gardening, or consider avoiding it, to prevent soil contact.

• Litter Box Avoidance During Pregnancy: If possible, avoid cleaning cat litter boxes during pregnancy.

Complications

Congenital toxoplasmosis can lead to various complications:

• Intrauterine Growth Restriction (IUGR): Reduced fetal growth within the uterus.

• Chorioretinitis: Inflammation of the retina and choroid, causing blurred vision, photophobia, and epiphora.

• Cerebral Calcifications: Calcium deposits in brain tissue.

• Toxoplasmic Encephalitis: Brain inflammation due to toxoplasmosis.

• Intellectual Disability: Impaired cognitive function.

• Seizures: Recurrent, uncontrolled brain electrical disturbances.

Nursing Diagnoses for Toxoplasmosis

Common nursing diagnoses for toxoplasmosis patients include:

• Hyperthermia: Related to parasitic infection secondary to toxoplasmosis, as evidenced by temperature of 38.5°C, rapid shallow breathing, flushed skin, diaphoresis, and weak pulse.

• Knowledge Deficit: Related to new diagnosis of toxoplasmosis, as verbalized by the patient expressing a desire for more information about their condition, cause, and treatment.