Toxoplasmosis - Symptoms, Causes, Images, and Treatment Options

Diseases

Highlights & Basics

Key Highlights

Toxoplasmosis is a protozoan parasite that spreads through food or water contaminated with oocysts, infected meat, or contact with oocysts from feline feces.
Acute infection is usually asymptomatic, and once acquired, parasites remain in human tissues lifelong.
Symptomatic disease can be seen in patients who are immunocompromised with reactivation of latent infection or with acquisition of new infection.
Symptomatic eye disease can be seen in both patients who are immunocompromised and patients who are immunocompetent.
Primary infection during pregnancy is often asymptomatic in the mother but can result in congenital disease in the fetus.

Pre- and post-treatment retinochoroiditis

From the collection of Rima L. McLeod, MD, and published in: Roberts F, McLeod R. Pathogenesis of toxoplasmic retinochoroiditis. Parasitol Today. 1999 Feb;15(2):51-7; used with permission

Quick Reference

History & Exam
- Key Factors
- Other Factors
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Diagnostics Tests
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Treatment Options
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Definition

Epidemiology

Etiology

Pathophysiology

Images

Computed tomography: brain of central nervous system toxoplasmosis
Brain pathology: while this is pathology from mouse tissue, it is quite similar to the appearance in human tissue
Pre- and post-treatment magnetic resonance imaging: brain of central nervous system toxoplasmosis
Pre- and post-treatment retinochoroiditis

Citations

Key Articles

Maldonado YA, Read JS, Committee on Infectious Diseases. Diagnosis, treatment, and prevention of congenital toxoplasmosis in the United States. Pediatrics. 2017 Feb;139(2):e20163860.[Full Text]
Centers for Disease Control and Prevention. CDC Yellow Book 2024: health information for international travel. Section 5: travel-associated infections & diseases - toxoplasmosis. May 2023 [internet publication].[Full Text]
Department of Health and Human Services, Panel on Opportunistic Infections in HIV-Infected Adults and Adolescents. Guidelines for the prevention and treatment of opportunistic infections in adults and adolescents with HIV: recommendations from the Centers for Disease Control and Prevention, the National Institutes of Health, and the HIV Medicine Association of the Infectious Diseases Society of America. May 2024 [internet publication].[Full Text]
Hoz RM La, Morris MI; Infectious Diseases Community of Practice of the American Society of Transplantation. Tissue and blood protozoa including toxoplasmosis, Chagas disease, leishmaniasis, Babesia, Acanthamoeba, Balamuthia, and Naegleria in solid organ transplant recipients - guidelines from the American Society of Transplantation Infectious Diseases Community of Practice. Clin Transplant. 2019 Sep;33(9):e13546.[Abstract]
Desmonts G. Couvreur J. Congenital toxoplasmosis: a prospective study of 378 pregnancies. N Eng J Med. 1974 May 16;290(20):1110-6.[Abstract]
Department of Health and Human Services, Panel on Opportunistic Infections in Children with and Exposed to HIV. Guidelines for the prevention and treatment of opportunistic infections in children with and exposed to HIV. Aug 2023 [internet publication].[Full Text]
McLeod R, Boyer K, Karrison T, et al. Outcome of treatment for congenital toxoplasmosis, 1981-2004: the National Collaborative Chicago-Based, Congenital Toxoplasmosis Study. Clin Infect Dis. 2006 May 15;42(10):1383-94.[Abstract]
Pradhan E, Bhandari S, Gilbert RE, et al. Antibiotics versus no treatment for toxoplasma retinochoroiditis. Cochrane Database Syst Rev. 2016 May 20;(5):CD002218.[Abstract][Full Text]

Other Online Resources

Dr. Jack S. Remington Laboratory for Specialty Diagnostics (Palo Alto, CA)
Toxoplasmosis Research Institute and Center (Chicago, IL)

Referenced Articles

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