Objective: Cerebrospinal fluid (CSF) white blood cell (WBC) count, neutrophil percentage, protein concentration, and glucose level are typically measured at diagnosis and serially during the treatment of CSF shunt infections. The objective of this retrospective cohort study was to describe the longitudinal profile of CSF parameters in children with CSF shunt infections and assess their association with treatment and outcome.
Methods: Participants were children treated at 11 tertiary pediatric hospitals in Canada and the United States for CSF shunt infection, from July 1, 2013, through June 30, 2019, with hardware removal, external ventricular drain placement, intravenous antibiotics, and subsequent permanent shunt reinsertion. The relationship between CSF parameters and a complicated course (a composite outcome representing children with at least one of the following: contiguous soft-tissue infection, worsening hydrocephalus, CSF leak, intracranial bleed, brain abscess, venous thrombosis, reinfection after insertion of the new shunt, other complication, ICU admission, or death) was analyzed.
Results: A total of 109 children (median age 2.8 years, 44% female) were included in this study. CSF pleocytosis, elevated protein, and hypoglycorrhachia had sensitivities of 69%, 47%, and 38% for the diagnosis of culture-confirmed CSF shunt infection, respectively. The longitudinal profile of the neutrophil percentage followed a monotonic trend, decreasing by 1.5% (95% CI 1.0%-2.0%, p < 0.0001) per day over the course of treatment. The initial WBC count differed significantly between pathogens (p = 0.011), but the proportion of neutrophils, protein concentration, and glucose level did not, and was lowest with Cutibacterium acnes. The duration of antibiotic treatment and the time to shunt reinsertion were longer in patients with a higher initial neutrophil percentage. Fifty-eight patients (53%) had one or more complications during their admission. A neutrophil percentage > 44% (Youden index) in the initial CSF sample was associated with a 1.8-fold (95% CI 1.2- to 2.8-fold) higher relative risk of a complicated course. In a random-intercept, random-slope linear mixed-effects model, the longitudinal neutrophil trajectory differed significantly between patients with and without complications (p = 0.030).
Conclusions: A higher proportion of neutrophils in the CSF at diagnosis was associated with a complicated clinical course. Other CSF parameters were associated with treatment and outcome; however, wide variability in values may limit their clinical utility.
Keywords: CSF shunt infection; antibiotic duration; hydrocephalus; shunt reimplantation.