Clinical findings in 9 newborn foals with septic meningoencephalitis

Introduction/Objectives: Bacterial meningoencephalitis is a complication of neonatal septicemia. The objective of this study was to
report clinical, clinicopathological findings, treatment and outcome of a group of septic meningoencephalitic foals.
Methods: Retrospective study. All septic foals admitted to our
hospital (2004–2009) with a diagnosis of bacterial meningoencephalitis were included. Data assessed included signalment,
physical and neurologic examinations, blood work, sepsis score,
CSF analysis, cultures, treatments and outcome.
Results: Nine neonates were diagnosed using 1 of the following criteria: CSF culture (2/9), CSF cytology consistent with bacterial infection (8/9), and/or postmortem confirmation (6/7).
Most common clinical signs were depressed mental status (9/9),
tetraparesis (7/9), abnormal pupillary light reflexes (6/9), altered
suckling-reflex (6/9), seizures and/or nystagmus (4/9), and abnormal respiratory pattern (4/9). Clinicopathological alterations
were leucopenia with neutropenia (5/9), hyperfibrinogenemia (8/
8), and hyperlactatemia (6/6). Blood culture was positive in 6/9
foals. The most frequently cultured agent was Escherichia coli.
Pleocytosis (9/9), increased total protein (5/5) and intracellular
bacteria (4/9) were detected on CSF analysis. Only one animal
survived.
Discussion: Clinical signs reported are common and non-specific
of bacterial meningoencephalitis. Therefore, clinical diagnosis
might be difficult and overlooked. Commonly used antibiotics in
neonatal medicine are not appropriate to treat CNS infections. The
clinical suspicion of bacterial CNS infection is a reason to switch to
appropriate antimicrobial drugs with high blood-brain barrier
penetration. In the future, techniques such as MRI will help to
reach more definitive diagnoses.
Conclusions: Bacterial meningoencephalitis is a disease that may
be misdiagnosed and needs early and specific antibiotic therapy