A 33‐year‐old man with multiple ring‐enhancing lesions in the brain

Abstract

A 33-year-old male presented with inability to think clearly and not recalling the death of his younger brother who had unexpectedly died a few days earlier. Prior to this episode the patient had enjoyed his usual good state of health and worked as a correctional officer with negative HIV history. His memory continued to decline and he had increased lethargy.On physical examination the patient was afebrile without lymphadenopathy, organomegaly or skin lesions. A neurological examination revealed no focal deficits. Laboratory studies were all within normal limits, including a normal complete blood count (CBC) without lymphocytosis or abnormal circulating lymphoid cells. MRI revealed several hemorrhagic ring-enhancing lesions in the brain: one in the right temporal lobe and two in the left temporal lobe, and one in the right occipital lobe (Fig. 1). No other lesions were found in the chest, abdominal or the pelvic regions. NEUROPATHOLOGICAL FINDINGSHematoxylin and eosin-stained sections of the stereotactic biopsy tissue showed a perivascular mononuclear cell infiltrate consisting of small lymphoid cells with round to oval hyperchromatic nuclei, inconspicuous nucleoli and scant cytoplasm ( Fig. 2A). Mitotic figures as well as apoptotic nuclei were also seen (Fig. 2B).Immunohistochemistry showed that a majority of the lymphoid cells were positive for leukocyte common antigen CD45, T-cell markers CD3 (Fig. 3A), CD8, and focally positive for CD7. Rare CD4 positive cells were present. Most lymphoid cells were negative for CD20 (Fig. 3B), CD79a, CD56, CD30, ALK and cytokeratin.

A 64-year-old woman with rapid neurologic decline diagnosed with Toxoplasma encephalitis after presumed metastatic cancer

“…While in the hospital, she completed an initial contrast MRI study, and when the finer details of the report are reviewed, one can see mention of an irregular ring of enhancement. A broad differential should be considered for any patient who presents with a ring-enhancing brain lesion 8 – 14 ( Table 2 ). Toxoplasmosis commonly presents with ring-enhancing lesions, although there are typically multiple lesions present rather than one solitary mass.…”