A patient in their 60s with a history of hypertension, diabetes, and vascular disease underwent deceased donor kidney transplant (DDKT) addressing end-stage renal disease (ESRD). Prior to transplant, the patient received two doses of the BNT162b2 vaccine. Initially treated with induction immunosuppression including basiliximab and methylprednisolone, an elevated anti-A titer in the blood type B recipient prompted a transition from basiliximab to anti-thymocyte globulin (ATG). Cytopenias and delayed graft function (DGF) requiring hemodialysis increased suspicion for calcineurin inhibitor (CNI) toxicity, tacrolimus was discontinued, and the patient received an augmented corticosteroid regimen. Ongoing DGF and cytopenias prompted a biopsy of the graft on postoperative day seven, which suggested acute cellular rejection and antibody-mediated rejection. The patient was treated with another dose of ATG, a course of plasmapheresis, and was ultimately transitioned to maintenance immunosuppression including prednisone, mycophenolate, and belatacept. The early postoperative course was further complicated by donor-derived hepatitis C virus (HCV) infection, an intra-abdominal urine leak requiring drainage and nephrostomy tube placement, and pyelonephritis.
Six months after transplant, the patient developed the new onset of malaise, fatigue, cough, and fever. On admission, nasopharyngeal RT-PCR was positive for SARS-CoV-2 with a cycle threshold (Ct) of 27.1. Genomic sequencing identified the B.1.529 (Omicron) subvariant BA.1.1. Not requiring oxygen at that time, the patient received a five-day course of remdesivir, experienced improvement in symptomatology including defervescence, and was discharged.
24 days after the diagnosis of COVID-19, the patient was readmitted with worsening fatigue, cough, dyspnea, abdominal discomfort, and fever. Nasopharyngeal SARS-CoV-2 RT-PCR was again positive with a Ct of 24.4, and genomic sequencing identified Omicron BA.1.1. In the setting of a substantial oxygen requirement, the patient was treated with another five-day course of remdesivir and a ten-day course of dexamethasone. Genomic sequencing 38 days after COVID-19 diagnosis identified the de novo RdRp mutation V792I (G15814A) (Fig. 1). Figure 2A outlines the identification of this mutation in relation to prior remdesivir exposure.
In the setting of new abdominal swelling, computed tomography (CT) performed shortly after admission demonstrated a moderate right pleural effusion and mass-like soft tissue infiltration along the renal graft, contiguous with the abdominal wall (Fig. 2B). Further diagnostic evaluation yielded a serum Epstein Barr virus (EBV) viral load of 645,000 IU/mL as cytology from pleural fluid, flow cytometry from pleural fluid, and a retroperitoneal lymph node biopsy demonstrated cells suggesting EBV-positive diffuse large B-cell lymphoma (DLBCL) consistent with monomorphic post-transplant lymphoproliferative disorder (PTLD). The patient was treated with multiple cycles of anti-neoplastic therapy that included rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone. Three weeks after the initiation of chemotherapy, the patient developed new ulcerative, bullous, and necrotic cutaneous findings overlying the renal graft (Fig. 2C). Biopsy of these changes yielded EBV-positive lymphocytes consistent with PTLD. During the course of chemotherapy, the patient experienced severe cytopenias, gastrointestinal bleeding, and hemorrhagic shock. The patient progressed to ESRD, and belatacept and mycophenolate were discontinued. Encountering multiple other complications including cytomegalovirus viremia and bacterial infections over the course of an admission spanning three months, the patient’s cough, fever, and hypoxemia all resolved, their skin findings improved, EBV viremia decreased dramatically, and interval reimaging demonstrated decreased size of the patient’s renal graft and associated lymphadenopathy. Three months after the initial diagnosis of COVID-19, IgGs to SARS-CoV-2 nucleoprotein and spike were detectable, the Ct increased to 29.3, and the patient remained free of any symptoms suggesting active respiratory infection.
110 days after COVID-19 diagnosis, the patient developed a new onset of dry cough and rhinorrhea. Nasopharyngeal RT-PCR was positive for SARS-CoV-2 with a Ct of 23.3 (Omicron BA.1.1). RT-PCR for other respiratory pathogens was negative. Repeat RT-PCR one week later yielded a Ct of 22.6, and genomic sequencing at that time identified a de novo synonymous mutation in RdRp at K890 (Fig. 1). Providers monitored the patient’s mild symptoms, which gradually improved over the course of weeks. Ct 153 days after COVID-19 diagnosis performed when the patient was asymptomatic was 34.1. During the patient’s prolonged course of infection, two additional de novo non synonymous mutations were also identified in nsp6 and orf3 (Supplemental Table 1).