Uncertainties in the Diagnosis of Brain

Recent advances in brain imaging present new challenges for the diagnosis of brain cysticercosis, as illustrated by the following case. A 32-year-old woman was admitted to the neurology department with intracranial hypertension of 9 months duration, mild left hemiparesis (4/5), and a left babinski sign. Cerebrospinal fluid opening pressure was 300 mm H2O. The fluid contained 25 cells, 120 mg of protein, and 93 mg of glucose/ml. ELISA (enzyme-linked immunosorbent assay) test for cysticercus was positive. Plain and contrast-enhanced computed tomography (CT) findings were normal (Fig 1). Magnetic resonance (MR) study showed multiple parenchymatous and subarachnoid nodular lesions with diffuse inflammation around lesions, clearly suggestive of cysticercosis (Fig 2). The advantages of MR over CT for diagnosis of cerebral and subarachnoid cysticercosis have been reported (1–3). In our patient the CT scan was normal, although the MR showed multiple lesions of cysticercotic encephalitis. These findings have implications in regard not only to imaging studies but also to immunologic studies such as ELISA to detect antibodies against cysticerci. Until now CT has been used as the standard diagnostic test to determine sensitivity, specitivity, and predictive values for ELISA test for cysticercosis (4–5). If CT has limitations, the figures obtained by these have to be reassessed according to advances in MR imaging.