Diagnostic Approach and Management Algorithm for Human Immunodeficiency Virus (HIV)-Infected Patients with Central Nervous System (CNS) Symptoms or Signs that Might Potentially be Toxoplasmic Encephalitis (TE) - Flowchart
Diagnostic Approach and Management Algorithm for Human Immunodeficiency Virus (HIV)-Infected Patients with Central Nervous System (CNS) Symptoms or Signs that Might Potentially be Toxoplasmic Encephalitis (TE) - Flowchart Acquired Immunodeficiency Syndrome Acquired Immunodeficiency Syndrome
«Flowchart»

CNS signs/symptoms in HIV-positive patients

CNS signs/symptoms in HIV-positive patients

CNS signs/symptoms in HIV-positive patients

Request serology and proceed with algorithm that favors empirical treatment until results are known

Request serology and proceed with algorithm that favors empirical treatment until results are known

Request serology and proceed with algorithm that favors empirical treatment until results are known

End

End

End

Toxoplasma IgG antibody

Toxoplasma IgG antibody

Toxoplasma IgG antibody

Toxoplasma

Unknown

Unknown

Unknown

Positive

Positive

Positive

Negative

Negative

Negative

Diagnosis of TE unlikely

Diagnosis of TE unlikely

Diagnosis of TE unlikely

MRI if CT was initially performed

MRI if CT was initially performed

MRI if CT was initially performed

Workup for causes other than TE. Repeat MRI in 42-78 hours if all investigations negative.

Workup for causes other than TE. Repeat MRI in 42-78 hours if all investigations negative.

Workup for causes other than TE. Repeat MRI in 42-78 hours if all investigations negative.

Consider lumbar puncture (if the risk for herniation is judged to be low)


PCR for:


T. gondii
Epstein-Barr virus
JC virus


Cytology

Consider brain biopsy


Isolation, PCR
Histopathology
Immunoperoxidase
AFB, Giemsa, Gram stains

Consider lumbar puncture (if the risk for herniation is judged to be low)


PCR for:


T. gondii
Epstein-Barr virus
JC virus


Cytology

Consider brain biopsy


Isolation, PCR
Histopathology
Immunoperoxidase
AFB, Giemsa, Gram stains

Consider lumbar puncture (if the risk for herniation is judged to be low)


PCR for:


T. gondii
Epstein-Barr virus
JC virus


Cytology


PCR for:


T. gondii
Epstein-Barr virus
JC virus


T. gondii T. gondii
Epstein-Barr virus
JC virus
Cytology

Consider brain biopsy


Isolation, PCR
Histopathology
Immunoperoxidase
AFB, Giemsa, Gram stains


Isolation, PCR
Histopathology
Immunoperoxidase
AFB, Giemsa, Gram stains

Presumptive diagnosis of TE. Continue treatment for 3-6 wk followed by maintenance therapy.

Presumptive diagnosis of TE. Continue treatment for 3-6 wk followed by maintenance therapy.

Presumptive diagnosis of TE. Continue treatment for 3-6 wk followed by maintenance therapy.

Definitive diagnosis

Definitive diagnosis

Definitive diagnosis

Long list of possibilities if other symptoms, signs, or laboratory investigations are unrevealing

Long list of possibilities if other symptoms, signs, or laboratory investigations are unrevealing

Long list of possibilities if other symptoms, signs, or laboratory investigations are unrevealing

Consider lumbar puncture (if the risk for herniation is judged to be low)


PCR for:


T. gondii
Epstein-Barr virus
JC virus


Cytology

Consider brain biopsy


Isolation, PCR
Histopathology
Immunoperoxidase
AFB, Giemsa, Gram stains

Consider lumbar puncture (if the risk for herniation is judged to be low)


PCR for:


T. gondii
Epstein-Barr virus
JC virus


Cytology


PCR for:


T. gondii
Epstein-Barr virus
JC virus


T. gondii T. gondii
Epstein-Barr virus
JC virus
Cytology

Consider brain biopsy


Isolation, PCR
Histopathology
Immunoperoxidase
AFB, Giemsa, Gram stains


Isolation, PCR
Histopathology
Immunoperoxidase
AFB, Giemsa, Gram stains Consider lumbar puncture

Brain biopsy not available

Brain biopsy not available

Brain biopsy not available

Single lesion

Single lesion

Single lesion

Multiple lesions

Multiple lesions

Multiple lesions

If MRI not available

If MRI not available

If MRI not available

CT/MRI with contrast (MRI preferable) (Fig. E1)

CT/MRI with contrast (MRI preferable) (Fig. E1)

CT/MRI with contrast (MRI preferable) (Fig. E1)

Single lesion

Single lesion

Single lesion

Multiple lesions on CT/MRI

Multiple lesions on CT/MRI

Multiple lesions on CT/MRI

No lesions (if CT is negative, MRI is advised)

No lesions (if CT is negative, MRI is advised)

No lesions

Treat empirically for TE

Treat empirically for TE

Treat empirically for TE

No improvement clinically by 10-14 days or clinically deterioration by day 3

No improvement clinically by 10-14 days or clinically deterioration by day 3

No improvement

Improved clinically by 7 days

Improved clinically by 7 days

Improved clinically by 7 days