[Value of magnetic resonance in the diagnostic definition of neurotoxoplasmosis and in the assessment of the response to pharmacological treatment].
OBJECTIVE
We investigated the role of Magnetic Resonance Imaging (MRI) in the diagnosis of neurotoxoplasmosis and in the evaluation of drug treatment response.


METHODS
Twenty-six AIDS patients (22 men and 4 women, mean age 26.7 years) with clinical suspicion of neurotoxoplasmosis were examined. A patient was considered to have neurotoxoplasmosis if there were signs of focal neurologic impairment and a positive/questionable response to the serum test for Toxoplasma gondii. MR images were acquired with T1-weighted spin-echo (SE) and inversion recovery (IR) sequences and with T2-weighted SE sequences. Gd-DTPA was administered in all cases. After the beginning of therapy with sulfadiazine and pyrimethamine all patients were submitted to clinical and neuroradiologic follow-up for 60 days.


RESULTS
MR examinations on admission demonstrated at least one brain lesion in all patients and multifocal involvement in 70% of cases. Enhancing lesions were found in 90% of patients (83% ring enhancement, 4% focal enhancement, 3% mixed patterns). The most frequent lesion sites were the basal ganglia and thalami (70%). The brain lesions were subdivided into 4 groups by their morphology and signal patterns.


CONCLUSIONS
The time course of clinical and neuroradiologic responses demonstrates a rapid improvement after the first week of therapy, which stabilized after the second week. Pearson correlation between clinical and neuroradiologic treatment responses showed a nearly linear correlation (r = .97; p < .001). The diagnosis was then confirmed in all patients based on the positive response to the serum test for Toxoplasma gondii (IgG > 12 UI/mL) and/or clinical and neuroradiologic improvement after therapy.


CONCLUSIONS
This study demonstrates the accuracy of MRI in the detection of toxoplasmosis brain lesions and in the evaluation of treatment response.
Sparacia
G
G
Istituto di Radiologia P. Cignolini, Università degli Studi, Palermo. sparacia@unipa.it
Brancatelli
G
G
Sarno
C
C
De Maria
M
M
Lagalla
R
R
Filosto
L
L
D017088:AIDS-Related Opportunistic Infections / Q000188:drug therapy* / Q000473:pathology*; D000328:Adult; D000981:Antiprotozoal Agents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011739:Pyrimethamine / Q000627:therapeutic use*; D015203:Reproducibility of Results; D013411:Sulfadiazine / Q000627:therapeutic use*; D016781:Toxoplasmosis, Cerebral / Q000188:drug therapy* / Q000473:pathology*
D000981:Antiprotozoal Agents; D013411:Sulfadiazine; D011739:Pyrimethamine
Valore della Risonanza Magnetica nella definizione diagnostica della neurotoxoplasmosi e nella valutazione della risposta al trattamento farmacologico.