Cerebral Toxoplasmosis in a Diffuse Large B Cell Lymphoma Patient

Abstract

Disclosure: No potential conflicts of interest were disclosed.Background. Toxoplasmosis is an opportunistic protozoal infection that has, until now, probably been an underestimated cause of encephalitis in patients with hematological malignancies, independent of stem cell or bone marrow transplant. T and B cell depleting regimens are probably an important risk factor for reactivation of a latent toxoplasma infection in these patients.Case report. We describe a 62-year-old HIV-negative right-handed Caucasian female with systemic diffuse large B cell lymphoma who presented with sudden onset of high fever, headache, altered mental status, ataxia and findings of pancytopenia, a few days after receiving her final, 8 th cycle of rituximab, cyclophosphamide, vincristine, doxorubicin, prednisolone (R-CHOP) chemotherapy regimen. A progression of lymphoma to the central nervous system was suspected. MRI of the head revealed multiple on T2 and fluid attenuated inversion recovery (FLAIR) hyperintense parenchymal lesions with mild surrounding edema, located in both cerebral and cerebellar hemispheres that demonstrated moderate gadolinium enhancement. The polymerase chain reaction on cerebrospinal fluid (CSF PCR) was positive for Toxoplasma gondii. The patient was diagnosed with toxoplasmic encephalitis and successfully treated with sulfadiazine, pyrimethamine and folic acid. Due to the need for maintenance therapy with rituximab for lymphoma remission, the patient now continues with secondary prophylaxis of toxoplasmosis.Conclusions. With this case report, we wish to emphasize the need to consider cerebral toxoplasmosis in patients with hematological malignancies on immunosuppressive therapy when presenting with new neurologic deficits. In such patients, there are numerous differential diagnoses for cerebral toxoplasmosis, and the CNS lymphoma is the most difficult among all to distinguish it from. If left untreated, cerebral toxoplasmosis has a high mortality rate; therefore early recognition and treatment are of essential importance.

Neurotoxoplasmosis in a Patient with Chronic Lymphocytic Leukemia

“…Neurotoxoplasmosis remains a common cerebral opportunistic infection in patients with acquired immune deficiency syndrome. This case emphasizes the need to consider toxoplasmosis in immunocompromised patients with hematological malignancies, representing an emerging group at risk [ 2 3 4 5 ]. Early diagnosis is essential to ensure early treatment, but clinical presentation of cerebral toxoplasmosis is unspecific [ 4 ].…”

Toxoplasma Gondii Encephalitis from Mycophenolate Mofetil: A Case Report and Review

“…Diagnosis is typically made indirectly, with serology, or directly, with techniques such as polymerase chain reaction looking for T. gondii DNA [9]. Immunosuppressant implicated in the development of cerebral toxoplasmosis includes cyclosporine, azathioprine, tacrolimus, and methylprednisolone [13][14][15][16] as well as rituximab [17,18], infliximab [19], fingolimod [20] and adalimumab [21]. First-line treatment includes a combination of pyrimethamine, leucovorin and sulfadiazine.…”

Cerebral Toxoplasmosis: A Case Report with Correlation of Radiographic Imaging, Surgical Pathology, and Autopsy Findings

“…An eccentric (asymmetric) target sign may be seen on contrast T1-weighted images, which exhibits a small enhancing nodule along the wall of the enhancing ring. This is highly specific for cerebral toxoplasmosis, but is seen in less than 30% of cases (6, 7). Additionally, lesions in lymphoma tend to be more locally infiltrative and a butterfly-pattern of spread and enhancement is more suggestive of lymphoma.…”

“…In addition to HIV-infected patients, cerebral toxoplasmosis also occurs in other immunosuppressed individuals, such as those who have undergone bone marrow transplant (BMT). There are only rare case reports of toxoplasmosis in patients with hematologic malignancies independent of BMT (7). Our patient fell into this category as she completed her sixth and last round of chemotherapy for DLBCL approximately four months before she started developing neurological symptoms.…”

“…Rituximab does have a good safety profile; however, concerns of increasing risk of infection are being raised. It does cause a rapid depletion of B-cells, but may also influence T-cell immunity and predispose patients to opportunistic infections (7). This exact mechanism of T-cell immunity impairment is not entirely understood at the present time.…”