Aetiology of fever in patients with acute stroke.

OBJECTIVE: Fever in patients with acute stroke is usually related to infectious complications. In some cases, a focus of infection cannot be identified, fever does not respond to empirical antibiotic treatment and is thought to be due to the central nervous system lesion. The aim of this study was to determine the frequency and origin of fever in patients with acute stroke and the characteristics associated with the presence of fever.
DESIGN: A retrospective study of 36 months' duration.
SETTING: The study was carried out at 'Alexandra' Hospital, a tertiary care teaching centre in Athens, Greece.
SUBJECTS: A total of 330 patients hospitalized for acute stroke from June 1992 until July 1994.
RESULTS: In 37.6% of 330 patients, fever was noted; 22.7% had a documented infection and 14.8% had fever without a documented infection. In univariate analysis, older age was associated with the presence of fever (P = 0.001). The development of fever was associated with intracerebral haemorrhage versus ischaemic infarct (P < 0.001) and with the presence of mass effect (P < 0.001), transtentorial herniation (P < 0.001), intraventricular blood (P < 0. 001), and larger size of ischaemic infarct (P = 0.0001) and of haemorrhage (P = 0.0002). Patients with fever had lower scores on admission on the Glasgow Coma Scale (P = 0.0001) and the Scandinavian Stroke Scale (P = 0.0001). The development of fever was associated with prior use of an invasive technique (P < 0.001) and more specifically with urinary catheterization (P < 0.001), but not with the presence of risk factors for infection. Patients with fever had a worse outcome assessed by the Modified Rankin Scale (P = 0. 0001) and the Barthel Index (P = 0.0001). In multivariate analysis, age, Scandinavian Stroke Scale score and mass effect were found to be significantly associated with fever (P = 0.035, P = 0.0001 and P = 0.0004, respectively). Patients with fever without documented infection had an earlier onset of fever than those with infection (P = 0.0061). In a logistic regression analysis, the only factor predictive of fever without documented infection versus infection was earlier onset of fever (P = 0.029).
CONCLUSION: Patients with acute stroke who develop fever are older, suffer severe stroke, their fever is associated with the use of invasive techniques, and they have a poor outcome. In patients with fever without a focus of infection, the only characteristic that is different from patients with known infection is earlier onset of fever.