Characteristics of Patients with Hypereosinophilia on Peritoneal Dialysis and Haemodialysis

Background: Hypereosinophilia is defined as a persistently raised eosinophil count of >1.5 x 109/L on at least 2 occasions 1 months apart. The prevalence of hypereosinophilia in the haemodialysis (HD) population has been reported to be up to 5% in some studies. The cause is often unclear, but reactions to the dialyser membrane are felt to be a factor. With this in mind, we chose to look at our dialysis programme and to compare the characteristics between patients on HD versus peritoneal dialysis PD who had hypereosinophilia. Methods: We retrospectively reviewed patients on our dialysis programme who had documented episodes of hypereosinophilia between 2007 and 2024. Data were collected from the Renal and Pathology databases, and the parameters of interest included demographic data, mode of dialysis, peak eosinophil count, mortality, diabetes status and whether the hypereosinophilia resolved. Resolution of the hypereosinophilia was defined as a fall below 1.5 x 109/L sustained over at least 3 months. Patients were also stratified according to peak eosinophil count: Group A: 1.5-5 x109/L, Group B: 5.1-10 x109/L and Group C >10 X109/L. Results: There were 211 HD patients and 21 PD patients who met the inclusion criteria. The demographic data are shown in table 1. There was no significant difference in mortality between the two modalities – 56% in the HD group and 57% in the PD group. Resolution of the hypereosinophilia was more common in the HD patients (82%), than patients on PD (67%). The proportion of patients in Group C (>10 X109/L) was lowest in the PD patients. Conclusion: There was no obvious difference in the demographic data between patients on HD and PD with hyperesoinophilia. The patients with more severe eosinophilia however, were more likely to be on haemodialysis. Resolution of the hypereosinophilia was more common in the HD patients, which argues somewhat against switching modality from HD to PD as a potential management strategy.