Haemophilus influenzae Meningitis in Infant Rats: Role of Bacteremia in Pathogenesis of Age-Dependent Inflammatory Responses in Cerebrospinal Fluid

Abstract

Abnormalities in cerebrospinal fluid associated with meningitis due to Haemophilus injluenzae type b were characterized in infant rats. After intranasal inoculation of bacteria, the development of intense bacteremia (> 10⁴ colony-forming unitsjml) correlated with cultures of cerebrospinal fluid positive for H. infiuenzae, with pleocytosis, and with histologic evidence of meningitis. The degree of pleocytosis was related to the age of the animal, the amount of time since inoculation, and the severity of the meningitis.