Background: Parvovirus B19-associated pure red cell aplasia (PVB19-PRCA) is an uncommon but serious complication after kidney transplantation. Currently, intravenous immunoglobulin (IVIG) is preferred as the first-line treatment for PVB19-PRCA, but presents with disadvantages of disease recurrence and expensive cost. In this context, we propose that foscarnet therapy for kidney transplantation recipients (KTR) with PVB19-PRCA may be an alternative scenario. No related study has been reported, and we performed this study to assess the efficacy and safety of foscarnet for PVB19-associated PRCA in KTR.
Methods: We conducted a retrospective review of PVB19-PRCA in KTR at our center over 9-year period. The data on therapy and outcomes in all cases treated with foscarnet are detailed records and summarized.
Results: Among our 68 patients, PVB19-PRCA was confirmed in 50 based on inclusion/exclusion criteria. All patients presented with refractory anemia and low reticulocyte percentage (< 0.5%), the mean hemoglobin of patients was 79.8± 12.6g/L at the time of PVB19-PRCA was identified. The median serum genome copy number of parvovirus B19 at diagnosis was 9.6 log₁₀ copies per milliliter. A total of 11 patients received foscarnet therapy, of 10 patients responded well to the treatment and maintained no recurrence. But 1 patient had a poor response to foscarnet therapy. Except for this patient, the mean hemoglobin level gradually increased from 68.5± 9.3 g/L to 73.2± 8.8 g/L, and the mean percentage of reticulocytes steadily increased from 0.1± 0.0% to 7.6± 2.9% after foscarnet therapy. The median serum genome copy number of parvovirus B19 decreased from 9.8 log₁₀ to 6.1 log₁₀ copies per milliliter. There was no significant difference (P=0.61, 0.60) in serum creatinine and glomerular filtration rate before and after foscarnet treatment. At the latest follow-up, the mean hemoglobin was 131.5± 12.5 g/L and the hemoglobin correction occurred in all patients.
Conclusion: Foscarnet therapy doesn’t seem to be worse than IVIG for PVB19-PRCA in KTR, and it can be an alternative option.
Keywords: human parvovirus B19, pure red cell aplasia, foscarnet therapy, kidney transplantation