Late Cytomegalovirus Primoinfection in a Heart Transplant Recipient After COVID-19 Vaccine

INTRODUCTION: Cytomegalovirus [CMV] is a frequent infection in solid organ transplant recipients and the mRNA COVID-19 vaccine has been associated with transient lymphopenia, which could be a risk factor to consider for CMV replication. CASE REPORT: A 51-year-old man with arterial hypertension and a history of repaired complex congenital heart disease, which required a heart transplant [HT] in 2019. He had a high risk CMV missmatch (D+/R-). Routine HT follow up tests after the first year were normal, with neither signs of rejection nor allograft vascular disease. His immunosuppressive treatment consisted in Tacrolimus 5 mg once a day, Mycophelonate 500 mg twice a day, and Prednisone 5 mg a day. 77 weeks after his heart transplant, two doses of mRNA COVID-19 vaccine were inoculated separated by 28 days. After 4 days of the second dose, he developed fever, diarrhea, and general malaise. The physical findings were abdominal pain, slight hepatomegaly and several painful gum lesions. Laboratory tests showed severe lymphopenia; and elevated C-reactive protein. CMV by polymerase chain reaction was tested positive with 228.356 copies/ml. The decision was to admit him and to initiate intravenous ganciclovir 5 mg/kg twice a day and to reduce the immunosuppressive treatment. He completed a course of 15 days with ganciclovir, and then continued with valganciclovir 900 mg twice a day. Early after ganciclovir start, clinical manifestations gradually disappeared. Due to persistent lymphopenia, mycophenolate was switched to everolimus. After 60 days of antiviral treatment, CMV loading was below detection range (Image 1). SUMMARY: The probability of favoring CMV replicability after mRNA COVID-19 vaccine has not been yet described. We here present a case of CMV primoinfection closely related in time with a full mRNA COVID-19 vaccine administration. We hypothesize that lymphopenia and a high risk CMV could be factors to consider at the time of mRNA COVID-19 vaccine administration. A close CMV monitoring should be advised in this scenario.