Diagnosis of Toxoplasma meningoencephalitis in a non-AIDS patient using PCR

Incidence, immunological and clinical characteristics of reactivation of latent Toxoplasma gondii infection in HIV-infected patients

To determine changes in incidence of reactivation of Toxoplasma gondii infection, manifesting as toxoplasmic encephalitis, and to assess the immunological mechanisms controlling reactivation in HIV-infected patients, a Czech cohort of 502 HIV/T. gondii co-infected patients was followed for 2909·3 person-years. The incidence of toxoplasmic encephalitis between the periods before and after the introduction of combination antiretroviral therapy (cART) was compared. Toxoplasmic encephalitis was diagnosed in 21 patients. In those patients the geometric mean value of CD4+ T lymphocytes was 12·6 times lower than in patients with non-reactivated T. gondii infection but an additionally significant decline in CD8+ T lymphocytes (3·3-fold) and natural killer cells (4·3-fold) was observed. This confirms the significance of these parameters. A twelvefold decrease in Toxoplasma reactivation incidence (40·2 vs. 3·4/1000 person-years) between monitored periods was seen. In the cART era, Toxoplasma reactivation was observed only in patients with unrecognized HIV infection or refusing therapy.

Cerebral toxoplasmosis combined with disseminated tuberculosis

A 24-year-old man presented with mental change, fever, abdominal pain, tenderness and palpable mass on the lower abdomen. He was a non-Korean engineer and did not accompany a legal guardian, so medical history taking was difficult due to his mental status. Brain magnetic resonance imaging showed multiple rim-enhanced lesions of the brain, and abdominal computed tomography showed huge paraspinal abscess. Chest X-ray and computed tomography showed poorly defined nodular opacities. We initially thought that this patient was infected with toxoplasmosis with typical cerebral image finding and immunoglobulin laboratory finding of cerebrospinal fluid and serum study. The abdominal abscess was confirmed as tuberculosis through the pathologic finding of caseous necrosis. We used anti-tuberculosis medication and anti-toxoplasmosis medication for almost 4 months, and then his clinical state and radiological findings were considerably improved.

Utility of molecular and serodiagnostic tools in cerebral toxoplasmosis with and without tuberculous meningitis in AIDS patients: A study from South India

Background:

Antemortem diagnosis of cerebral toxoplasmosis, the second most common opportunistic infection (OI) in HIV-infected individuals in developing countries is a challenge.

Materials and Methods:

Toxoplasma gondii (T.gondii) -specific serology and nested polymerase chain reaction (nPCR) were evaluated in sera and ventricular/lumbar cerebrospinal fluid (CSF) of 22 autopsy confirmed cases of cerebral toxoplasmosis with HIV and 17 controls. Frequency of concomitant T.gondii infection was investigated in 17 cases of HIV-associated tuberculous meningitis (TBM).

Results:

The sensitivity, specificity, and positive and negative predictive values of T. gondii IgG on CSF (ventricular and lumbar) and sera was 100% in histology proven cerebral toxoplasmosis (concentrations: 258 ± 50, 231 ± 36, and 646 ± 243 IU/mL, respectively); majority (94%) being high avidity type, suggesting reactivation/reinfection. The sensitivity of B1 nPCR was 100% on ventricular CSF, whereas it was only 77% on lumbar CSF. Based on histology, nPCR, and IgG serology, T. gondii co-infection with TBM was observed in 65% (11/17) of cases.

Discussion and Conclusion:

CSF IgG serology and nPCR are tests with high sensitivity and specificity for the diagnosis of cerebral toxoplasmosis. TBM and cerebral toxoplasmosis can coexist and should be considered in the background of HIV infection in developing countries.

[Toxoplasmic encephalitis and cytomegaloviral retinitis in a non-AIDS patient with chronic renal failure undergoing corticosteroid therapy]

We report a rare case of toxoplasmic encephalitis in a non-AIDS patient A 62-year-old man undergoing hemodialysis for seven months and corticosteroid therapy for rapidly progressive glomerulonephritis and admitted for generalized convulsions was found in cranial magnetic resonance imaging (MRI) to have multiple ring-enhanced lesions. Antibodies against Toxoplasma gondii, and in Sabin-Feldman dye test were extremely high, yielding a diagnosis of toxoplasmic encephalitis. He was also diagnosed as having cytomegaloviral retinitis. Anti-HIV antibody was negative. Treatment with pyrimethamine and clindamycin was effective and intracerebral lesions disappeared. Physicians encounting a similar situation should consider toxoplasmic encephalitis as a differential diagnosis, even in non-HIV patients, and implement confirmational examination.