Eosinophil activation in the cerebrospinal fluid of children with shunt obstruction

Objective: To determine if eosinophils are activated to release the cationic proteins, eosinophil cationic protein (ECP) and eosinophil-derived neurotoxin (EDN) in shunt obstruction, and to find out if these proteins are associated with ventriculoperitoneal shunt failure. Patients and Methods: This was a prospective observational study carried out in a 20-bed tertiary pediatric intensive care unit. Patients studied were children aged 0-18 years with suspected ventriculoperitoneal shunt malfunction requiring shunt revision. No interventions were performed. Cerebrospinal fluid (CSF) was analyzed for cell count and EDN and ECP concentrations. Patients were prospectively followed for 6 months to evaluate shunt failure. Results: In a 2-month period, 56 shunt revisions were performed on 56 children. Three children had culture-proven infection. Eosinophilia, defined as ≥5% eosinophils in the CSF, was present in 9 out of 53 children (17%). The 3 patients with infection did not have eosinophilia and were excluded from further analysis. Patients with CSF eosinophilia had higher concentrations of ECP (1.38 ± 0.66 vs. 0.41 ± 0.15 ng/ml; p = 0.013) and EDN (16.94 ± 5.83 vs. 4.69 ± 1.33 ng/ml; p = 0.011). Patients with CSF eosinophilia did not have more ventriculoperitoneal shunt revisions within 6 months (6 of 9) compared to those who did not have eosinophilia (21 of 44; p = 0.50). However, patients with higher levels of ECP in the CSF required more shunt revisions within 6 months of their surgeries (p < 0.05). Conclusions: In patients with malfunctioning ventriculoperitoneal shunts, CSF eosinophils are activated and release ECP and EDN. The presence of ECP is associated with a shorter shunt life.