Central nervous system complications in patients with bacteremia.

The occurrence of central nervous system (CNS) complications was studied retrospectively in 150 patients with bacteremia caused by Staphylococcus aureus, Streptococcus pneumoniae, beta-hemolytic streptococci or Escherichia coli. The incidence and clinical manifestations of different CNS complications were noted during 1 month after the bacteremia. Special attention was paid to vascular complications (infarction or hemorrhage), infections (meningitis or brain abscess) and mental changes when they were the only signs of CNS origin (lowered level of consciousness, confusion or delirium). The risk of cerebral infarction was elevated in the patients with bacteremia during the first month after the positive blood culture as compared with the overall risk of stroke in the general population. 10/150 patients (7%) developed cerebral infarction during that month. Two of these cases were associated with bacterial meningitis and 1 with endocarditis. Mental changes as a main symptom of CNS origin occurred in 27% of patients with bacteremia. Increasing patient age predisposed to this complication. Mental changes were not associated with any bacterial species studied. Altogether 40% of the patients developed CNS complications, which were a significant risk factor for death during the first month after the bacteremia.