Primary cerebral abscess due to nocardia presenting as 'ghost tumor'. Clinical and pathological study.

We report a case of a primary cerebral abscess due to Nocardia asteroides in a nonimmunocompromised patient with a particular clinical course. The first symptom (right subacute brachial palsy) and the lesion in a computed tomographic (CT) scan (left parietofrontal edema suggestive of brain tumor) disappeared after corticosteroid treatment and the patient was discharged with total recovery. After 2 months she complained of headache and visual disturbance. A new CT scan showed an annular lesion in the left occipital lobe. A cerebral biopsy was diagnosed of nocardia infection. The patient died 2 weeks after this biopsy. A postmortem study showed an occipital brain abscess but not structural abnormalities were seen in the left parietofrontal area. We believe that the first episode could be a local inflammatory response to cerebral implantation of nocardia which disappeared clinically in the CT scan and in the postmortem study after corticosteroid treatment. Then the nocardia could have displaced by the hematological route to the second and definitive cerebral lesion.

Contralateral trigeminal neuralgia as a false localizing sign in intracranial tumors.

Three cases of contralateral trigeminal neuralgia as a false localizing sign in intracranial tumors are reported. In each patient (meningioma, 2 cases; cholesteatoma, 1 case) the tumor was asymptomatic, so that intracranial tumor had not been suspected preoperatively. In all cases, tumors were large and firm. The tumor was supratentorial in two cases. In one case, a cortically mediated mechanism may have caused the neuralgia, whereas in the remaining two cases distortion and displacement of the brain stem and compression of the contralateral Meckel's cave would explain the trigeminal nerve signs.