We present a case of cytomegalovirus (CMV) retinitis with UL97 resistance in a patient undergoing treatment for acute myeloid leukemia (AML), highlighting the complex interplay between hematological malignancies and CMV management. A 49-year-old female patient with myelodysplastic syndromes (MDS) with 4.5% blasts and TP53 mutations ((variant allele frequency (VAF)) 5.2%) underwent an allogeneic stem cell transplant complicated by acute graft versus host disease (GvHD) and subsequent CMV viremia. The gene discussed is TP53; the disease is graft versus host disease.