Unexpected eosinophilia in children affected by hydrocephalus accompanied with shunt infection

PURPOSE: The aim of the article is to describe an immunological reaction to shunt infection in children with hydrocephalus. The main cause of shunt infection involves methicillin resistant Staphylococcus epidermidis (Bhatia et al. Indian J Med Microbiol 35:120–123, 2017; Hayhurst et al. Childs Nerv Syst 24:557–562, 2008; Martínez-Lage et al. Childs Nerv Syst 26: 1795–1798, 2010; Simon et al. PLoS One, 2014; Snowden et al. PLoS One 8:e84089, 2013; Turgut et al. Pediatr Neurosurg 41:131–136, 2005), a bacterial strain which is responsible for the formation of biofilm on contaminated catheters (Snowden et al. PLoS One 8:e84089, 2013; Stevens et al. Br J of Neurosurg 26: 792–797, 2012). METHODS: The study group involved 30 children with congenital hydrocephalus after shunt system implantation, whose procedures were complicated by S. epidermidis implant infection. Thirty children with congenital hydrocephalus awaiting their first-time shunt implantation formed the control group. The level of eosinophils in peripheral blood was assessed in both groups. Cerebrospinal fluid (CSF) was examined for protein level, pleocytosis, interleukins, CCL26/Eotaxin-3, IL-5, IL-6, CCL11/Eotaxin-1, CCL3/MIP-1a, and MBP. Three measurements were performed in the study group. The first measurement was obtained at the time of shunt infection diagnosis, the second one at the time of the first sterile shunt, and the third one at the time of shunt reimplantation. In the control group, blood and CSF samples were taken once, at the time of shunt implantation. RESULTS: In the clinical material, the highest values of eosinophils in peripheral blood and CSF pleocytosis were observed in the second measurement. It was accompanied by an increase in the majority of analyzed CSF interleukins. CONCLUSION: CSF pleocytosis observed in the study group shortly after CSF sterilization is presumably related to an allergic reaction to Staphylococcus epidermidis, the causative agent of ventriculoperitoneal shunt infection.