Toxoplasma gondii Encephalitis

Encephalitis caused by Toxoplasma gondii

Primary Prophylaxis

Start: if CD4 count < 200 cells/μL, or CD4 percentage < 14%, oral thrush, or relevant concomitant immunosuppression, see Primary prophylaxis of OIs
Stop: if CD4 count > 100 cells/μL and HIV-VL undetectable over 3 months

  Drug / Dose Comments
Preferred prophylaxis TMP-SMX
800/160 mg 3/week po
or 400/80 mg qd po
or 800/160 mg qd po
All regimens are also effective against PcP
Alternative prophylaxis atovaquone suspension
1500 mg qd po (with food)
 
dapsone
200 mg/week po
+ pyrimethamine
75 mg/week po
+ folinic acid
25-30 mg/week po
Check for G6PD-deficiency
atovaquone suspension
1500 mg qd po (with food)
+ pyrimethamine
75 mg/week po
+ folinic acid
25-30 mg/week po
 

Treatment

Treat 6 weeks, then secondary prophylaxis until CD4 count > 200 cells/μL and HIV-VL undetectable over 6 months
Diagnosis:

    • Definitive diagnosis: clinical symptoms, typical radiology of the cerebrum AND cytological / histological detection of organism in tissue
    • Presumptive diagnosis: clinical symptoms, typical radiology AND response to empirical treatment. It is the standard in most clinical settings
  Drug / Dose Comments
Preferred therapy

pyrimethamine
Day 1: 200 mg qd po,
then
If ≥ 60 kg: 75 mg qd po;
If < 60 kg: 50 mg qd po

+ sulfadiazine
If ≥ 60 kg: 3000 mg bid po/iv;
If < 60 kg: 2000 mg bid po/iv

+ folinic acid
10-15 mg/day po

Monitor for myelotoxicity of pyrimethamine, mostly neutropenia

Sulfadiazine is associated with crystalluria and may lead to renal failure and urolithiasis. Good hydration is essential. Check renal function and urine sediment for microhematuria and crystalluria

Alternative therapy

pyrimethamine
Day 1: 200 mg qd po,
then
If ≥ 60 kg: 75 mg qd po;
If < 60 kg: 50 mg qd po

+ clindamycin
600-900 mg qid po/iv

+ folinic acid
10-15 mg qd po

Monitor for myelotoxicity of pyrimethamine, mostly neutropenia

Additional PcP prophylaxis is necessary, where required

  OR TMP-SMX
5 mg TMP/kg bid iv/po,
25 mg SMX/kg bid iv/po
Preferred intravenous regimen if oral route not possible
 

OR pyrimethamine
Day 1: 200 mg qd po,
then

If ≥ 60 kg: 75 mg qd po;
If < 60 kg: 50 mg qd po

+ atovaquone
1500 mg bid po (with food)

+ folinic acid
10-15 mg qd po

Monitor for myelotoxicity of pyrimethamine, mostly neutropenia
 

OR sulfadiazine
If ≥ 60 kg: 3000 mg bid po/iv;
If < 60 kg: 2000 mg bid po/iv

+ atovaquone
1500 mg bid po (with food)

Sulfadiazine is associated with crystalluria and may lead to renal failure and urolithiasis. Good hydration is essential. Check renal function and urine sediment for microhematuria and crystalluria

 

OR pyrimethamine
Day 1: 200 mg qd po,
then
If ≥ 60 kg: 75 mg qd po;
If < 60 kg: 50 mg qd po

+ azitromycin
900-1200 mg qd po

+ folinic acid
10-15 mg qd po

Monitor for myelotoxicity of pyrimethamine, mostly neutropenia

Secondary Prophylaxis, Maintenance Therapy

Stop: if CD4 count > 200 cells/μL and HIV-VL undetectable over 6 months

Regimens listed are alternatives

Drug / Dose Comments
sulfadiazine
2000-3000 mg bid - qid po
+ pyrimethamine
25-50 mg qd po
+ folinic acid
10-15 mg qd po
 
OR clindamycin
600 mg tid po
+ pyrimethamine
25-50 mg qd po
+ folinic acid
10-15 mg qd po
Additional PCP prophylaxis is necessary
OR atovaquone suspension
750-1500 mg bid po (with food)
+ pyrimethamine
25-50 mg qd po
+ folinic acid
10-15 mg qd po
 
OR atovaquone suspension
750-1500 mg bid po (with food)
 
OR TMP-SMX
800/160 mg bid po