Parvovirus B19 IgG-Defined Prior Exposure and Its Association with Anemia in Maintenance Hemodialysis Patients: A...

Background: Parvovirus B19 (B19V) has a well-established tropism for erythroid progenitor cells and is a recognized cause of anemia in immunocompromised individuals. Patients with end-stage renal disease (ESRD) receiving maintenance hemodialysis are predisposed to anemia due to multiple mechanisms and are frequently exposed to healthcare settings, raising concern that prior B19V infection may contribute to anemia severity or resistance to erythropoiesis-stimulating agents (ESAs). However, data regarding the clinical relevance of B19V seroprevalence in hemodialysis patients remain limited. Methods: We conducted a single-center, observational cross-sectional study including 131 adult patients on maintenance hemodialysis and 50 healthy controls. Parvovirus B19 IgG serostatus was assessed by enzyme-linked immunosorbent assay (ELISA) and used exclusively as a marker of prior (past) exposure rather than active infection; our aim was to determine whether IgG-defined prior exposure leaves a measurable long-term imprint on erythropoiesis. None of the participants had clinical features suggestive of acute parvovirus infection or an unexplained aplastic episode at enrollment. Demographic data, comorbidities, dialysis characteristics, ESA use, and laboratory parameters (hemoglobin, hematocrit, mean corpuscular volume, inflammatory markers, and albumin) were collected. Between-group and within-cohort comparisons used non-parametric tests, and multivariable logistic and linear regression models were used to adjust for age, sex, and other relevant covariates. Results: Parvovirus B19 IgG seropositivity was common in both groups (64.9% of hemodialysis patients vs. 48% of controls; crude odds ratio [OR] 2.00, 95% confidence interval [CI] 1.03-3.88, p = 0.043). However, hemodialysis patients were substantially older and more often male; after adjustment for age and sex, dialysis status was no longer independently associated with seropositivity (adjusted OR 1.4, 95% CI 0.8-2.3, p = 0.20), and within the hemodialysis cohort seropositivity was not associated with age or sex. Hemodialysis patients exhibited significantly lower hemoglobin and hematocrit and higher inflammatory markers than controls, consistent with ESRD-related anemia. Within the hemodialysis cohort, B19 IgG-positive and IgG-negative patients did not differ in hemoglobin, hematocrit, mean corpuscular volume, C-reactive protein, albumin, or ESA use, and IgG serostatus remained unrelated to hemoglobin in a multivariable model adjusting for age, sex, inflammation, nutrition, dialysis vintage, and ESA use (adjusted β = -0.20 g/dL, 95% CI -0.68 to 0.28, p = 0.42). Past Parvovirus B19 exposure was therefore not associated with anemia severity or treatment requirements. Conclusions: In this cohort of stable maintenance hemodialysis patients, prior Parvovirus B19 exposure, as indicated by IgG seropositivity, was not associated with increased anemia severity, inflammation, or ESA use, and the higher crude seroprevalence in dialysis patients was attributable to their older age rather than to dialysis itself. Because IgG reflects past exposure only and IgM and viral DNA were not assessed, these findings apply strictly to past (IgG-defined) exposure and cannot address active or persistent B19V infection. They suggest that routine Parvovirus B19 IgG screening in asymptomatic hemodialysis patients is unlikely to be useful for anemia management, whereas active or persistent infection-detectable only by molecular testing-remains the more plausible contributor to unexplained or refractory anemia and merits study in selected patients.