ABSTRACT
When faced with the neuropathological examination of a case of possible CNS infection the main aims are to establish (i) the cause of the infection (Box 8.1); (ii) the route by which the nervous system was reached by the organism; and (iii) the effects the infection has had on the nervous system itself. This may be a relatively straightforward task, for example in a case of classical acute leptomeningitis due to pneumococcal infection with associated pneumonia and bacteremia. On the other hand, in another case, infection may not have been considered in the differential diagnosis, the naked-eye appearances at post mortem examination may be unremarkable, and the organism may be a relatively uncommon one. The pathologist needs to be particularly alert for infection when examining material from patients who, for one reason or another, may be suspected of being immuno - deficient. For example, the leptomeninges may appear uninflamed despite the presence of organisms in the subarachnoid space in such patients.
