Secondary prophylaxis for Toxoplasma gondii encephalitis in adults

Adults who have completed primary treatment for T. gondii should receive secondary prophylaxis to suppress infection. Continue secondary prophylaxis while the patient remains immunocompromised. For patients with HIV infection who are responding to antiretroviral therapy, continue secondary prophylaxis until CD4 count is more than 200 cells/microlitre for 6 months or longer.

For T. gondii encephalitis secondary prophylaxis (maintenance therapy) in adults, usePanel on guidelines for the prevention and treatment of opportunistic infections in adults and adolescents:

sulfadiazine 1 g orally, 12-hourly1. For dosage adjustment in adults with kidney impairment, see sulfadiazine dosage adjustmentsulfadiazinesulfadiazinesulfadiazine

PLUS

pyrimethamine 25 mg orally, daily2pyrimethaminepyrimethaminepyrimethamine

PLUS

calcium folinate 15 mg orally, daily3.calcium folinatecalcium folinatecalcium folinate

For adults hypersensitive to sulfonamides, use as a 3-drug regimen:

clindamycin 600 mg orally, 8-hourlyclindamycinclindamycinclindamycin

PLUS

pyrimethamine 25 mg orally, dailypyrimethaminepyrimethaminepyrimethamine

PLUS

calcium folinate 15 mg orally, daily3.calcium folinatecalcium folinatecalcium folinate

If trimethoprim+sulfamethoxazole was used for primary treatment, useInfectious Diseases Society of America (IDSA) 2017:

1trimethoprim+sulfamethoxazole 160+800 mg orally, twice daily. For dosage adjustment in adults with kidney impairment, see trimethoprim+sulfamethoxazole dosage adjustmenttrimethoprim + sulfamethoxazoletrimethoprim+sulfamethoxazoletrimethoprim+sulfamethoxazole

OR

2trimethoprim+sulfamethoxazole 160+800 mg orally, once daily4. For dosage adjustment in adults with kidney impairment, see trimethoprim+sulfamethoxazole dosage adjustment.
1 Sulfadiazine is not marketed in Australia but is available via the Special Access Scheme.Return
2 Pyrimethamine is not marketed in Australia but is available via the Special Access Scheme.Return
3 Calcium folinate reduces the incidence of neutropenia with pyrimethamine.Return
4 The once-daily trimethoprim+sulfamethoxazole regimen may be associated with an increased risk of relapse. If switching from the twice-daily to the once-daily regimen, consider undertaking a gradual transition (eg over 4 to 6 weeks).Infectious Diseases Society of America (IDSA) 2017Return