Anti-Borrelia IgG Seropositivity Among Hemodialysis Patients with Chronic Kidney Disease of Unknown Etiology: A Preliminary Case–Control Study from Northern Türkiye

Background: Lyme borreliosis is a multisystemic tick-borne infection caused by Borrelia burgdorferi sensu lato complex. Renal involvement is well documented in dogs with Lyme nephritis, whereas human renal manifestations have been reported only rarely, mainly as isolated case reports of glomerular disease. Because a proportion of chronic kidney disease (CKD) cases remain unexplained, we aimed to determine the possible contribution of previous exposure to idiopathic CKD. Methods: The study included 45 patients and 45 age and sex matched controls. Serum samples were tested for anti-Borrelia IgG using enzyme-linked immunosorbent assay (ELISA). Positive or borderline ELISA results were further evaluated by Western blot (WB) analysis. Results: Overall, anti-Borrelia IgG seropositivity was 5.55% with WB. In the CKD group, ELISA positivity was 11.1% and WB-confirmed positivity was 8.9%. In the control group, ELISA positivity was 4.4% and WB-confirmed positivity was 2.2%. (p > 0.05). All confirmed patients were living in rural areas, engaged in farming and/or animal husbandry, and reported repeated tick exposure. Conclusions: IgG seropositivity was numerically higher among patients with CKD of unknown etiology than among healthy controls; however, this difference was not statistically significant. Larger, risk-factor-adjusted studies are needed to clarify whether Borrelia exposure may be associated with unexplained CKD.