Toxoplasmosis

Last reviewed: 7 Jun 2022
Last updated: 07 Jun 2022

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • chorioretinitis
  • focal neurological deficit
More key diagnostic factors

Other diagnostic factors

  • blurry vision
  • slurred speech
  • headache
  • unsteady gait
  • confusion
  • fever
  • lymphadenopathy
  • fetal microcephaly
  • fetal intracranial calcification
  • fetal hydrocephalus
  • fetal intrauterine growth retardation
  • seizure
  • malaise
  • hepatitis
  • pneumonitis
  • myocarditis
Other diagnostic factors

Risk factors

  • immunosuppression
  • exposure during pregnancy
  • residence in a high-risk area
  • ingestion of undercooked or raw meat
  • exposure to cat faeces
  • heavy exposure to soil
  • ingestion of unwashed unpeeled raw fruits and vegetables
  • occupational exposure
More risk factors

Diagnostic investigations

1st investigations to order

  • anti-Toxoplasma IgG (serum)
  • anti-Toxoplasma IgM (serum)
  • CT (with intravenous contrast) or MRI of brain
More 1st investigations to order

Investigations to consider

  • anti-Toxoplasma IgA (serum)
  • anti-Toxoplasma IgE (serum)
  • Toxoplasma-specific IgG avidity index (serum)
  • differential agglutination test (AC/HS)
  • polymerase chain reaction (body fluids and tissue)
  • biopsy
More investigations to consider

Emerging tests

  • IgG or IgM Immunoblot (serum)
  • enzyme-linked immunosorbent spot assay
  • interferon-gamma release assay

Treatment algorithm

INITIAL

occupational exposure

HIV-positive with CD4+ T lymphocyte count <100

seronegative recipients of solid organs from seropositive donors; seropositive recipients of allogeneic haematopoietic stem cell transplant

ACUTE

newborns: confirmed or highly suspected congenital disease

non-pregnant adults and children: confirmed or suspected disease

pregnant: with seroconversion

ONGOING

immunocompromised: following symptomatic disease

Contributors

Authors

Sarah Hochman, MD

Assistant Professor

Department of Medicine

Division of Infectious Diseases and Immunology

New York University School of Medicine

New York

NY

Disclosures

SH declares that she has no competing interests.

Kami Kim, MD

Professor of Medicine (Infectious Diseases) and Microbiology and Immunology

Albert Einstein College of Medicine

Bronx

NY

Disclosures

KK is on the advisory board for the Sanford Guide for Antibiotic Therapy. KK is the author of a reference cited in this topic.

Peer reviewers

Fabrizio Bruschi, MD

Professor of Parasitology

University of Pisa

School of Medicine

Pisa

Italy

Disclosures

FB declares that he has no competing interests.

Srikrishna Nagri, MD

Gastroenterologist

Dartmouth-Hitchcock Nashua

Nashua

NH

Disclosures

SN declares that he has no competing interests.

George Y. Wu, MD, PhD

Professor of Medicine

University of Connecticut Health Center

Farmington

CT

Disclosures

GYW is on the medical advisory boards of the following: Gilead Sciences, Bristol-Myers Squibb, AbbVie, and Intercept.

  • Toxoplasmosis images
  • Differentials

    • Central nervous system lymphoma
    • Metastatic brain lesions from primary malignancy
    • Mycobacterial central nervous system disease
    More Differentials
  • Guidelines

    • Guidelines for the prevention and treatment of opportunistic infections in adults and adolescents with HIV
    • Guidelines for the prevention and treatment of opportunistic infections in HIV-exposed and HIV-infected children
    More Guidelines
  • Patient leaflets

    Toxoplasmosis in pregnancy: what is it?

    Toxoplasmosis in pregnancy: what treatments work?

    More Patient leaflets
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