What is the diagnosis and treatment of Toxoplasmosis (Toxoplasma gondii infection)?

From the Guidelines

Toxoplasmosis should be treated with a combination of pyrimethamine, sulfadiazine, and folinic acid for 12 months in infants with confirmed congenital toxoplasmosis, as this regimen has been shown to reduce the risk of severe neurologic sequelae and symptomatic disease. The treatment regimen typically consists of pyrimethamine (1 mg/kg per day) and sulfadiazine (100 mg/kg per day) for the first 2 months, followed by pyrimethamine (1 mg/kg per day) and sulfadiazine (100 mg/kg per day) three times a week for the remaining 10 months, along with folinic acid (10 mg three times a week) to prevent bone marrow suppression 1. This treatment approach is supported by studies from the National Reference Laboratory for Toxoplasmosis and the Toxoplasmosis Center, which have demonstrated the efficacy of this regimen in reducing the risk of severe disease and improving outcomes in infants with congenital toxoplasmosis.

Some key points to consider in the management of toxoplasmosis include:

• The importance of early diagnosis and treatment to prevent severe neurologic sequelae and symptomatic disease
• The use of spiramycin (1 g three times daily) in pregnant women to reduce the risk of maternal-fetal transmission
• The need for regular follow-up and monitoring of infants with congenital toxoplasmosis to detect any signs of disease or treatment failure
• The importance of preventive measures, such as thoroughly cooking meat, washing fruits and vegetables, avoiding cat feces, and wearing gloves when gardening, to reduce the risk of toxoplasmosis infection.

It is also important to note that the treatment regimen may vary depending on the severity of the disease and the patient's individual factors, and that alternative treatments, such as clindamycin or trimethoprim-sulfamethoxazole, may be considered in certain cases 1. However, the combination of pyrimethamine, sulfadiazine, and folinic acid remains the first-line treatment for congenital toxoplasmosis, and its use has been associated with improved outcomes and reduced morbidity and mortality.

From the FDA Drug Label

Pyrimethamine is indicated for the treatment of toxoplasmosis when used conjointly with a sulfonamide, since synergism exists with this combination. Concurrent administration of folinic acid is strongly recommended when used for the treatment of toxoplasmosis in all patients.

Pyrimethamine is used for the treatment of toxoplasmosis, and it is recommended to be used in combination with a sulfonamide. Additionally, folinic acid should be administered concurrently to prevent potential adverse effects. 2 2

From the Research

Definition and Prevalence of Toxoplasmosis

• Toxoplasmosis is a disease caused by the protozoan parasite Toxoplasma gondii, which infects up to a third of the world's population 3.
• The infection is mainly acquired by ingestion of food or water contaminated with oocysts shed by cats or by eating undercooked or raw meat containing tissue cysts 3.

Clinical Manifestations

• Primary infection is usually subclinical, but in some patients, cervical lymphadenopathy or ocular disease can be present 3.
• Infection acquired during pregnancy may cause severe damage to the fetus 4, 3.
• In immunocompromised patients, reactivation of latent disease can cause life-threatening encephalitis 5, 3.

Diagnosis

• Diagnosis of toxoplasmosis can be established by direct detection of the parasite or by serological techniques 3.
• Serologic screening should be offered only to pregnant women considered to be at risk for primary Toxoplasma gondii infection 4.

Treatment

• The most commonly used therapeutic regimen, and probably the most effective, is the combination of pyrimethamine with sulfadiazine and folinic acid 6, 5, 3.
• Spiramycin, a macrolide antibiotic, is frequently used alone or alternately with pyrimethamine and sulphonamide for pregnant women with the acute acquired infection to prevent congenital toxoplasmosis 6, 4.
• Clindamycin is used frequently to treat acute flares of toxoplasmic chorioretinitis and as second-line therapy for toxoplasmic encephalitis in patients with the acquired immunodeficiency syndrome (AIDS) 6, 5.
• Trimethoprim/sulfamethoxazole (TMP/SMX) appears to be useful for prophylaxis against toxoplasmosis in patients with AIDS 5.
• Dapsone in combination with pyrimethamine therapy may be an effective alternative for toxoplasmosis prophylaxis 5.

Prevention

• Information on prevention of Toxoplasma gondii infection in pregnancy should be made available to all women who are pregnant or planning a pregnancy 4.
• Prenatal care must include education about prevention of toxoplasmosis 4.
• Routine universal screening should not be performed for pregnant women at low risk 4.