ABSTRACT
Background: Cytomegalovirus (CMV) retinitis is an uncommon presentation post allogeneic transplant and can be vision-threatening. Our case demonstrates the occurrence of polymerase chain reaction proven mixed viral retinitis (cytomegalovirus and varicella zoster virus) post allogeneic stem cell transplant despite multiple prophylactic antiviral therapies, and features CMV retinitis in the absence of CMV DNAemia. This case highlights the emerging challenge of late CMV disease occurring during secondary prophylaxis with Letermovir.
Case presentation: A 21-year-old female with acute myeloid leukemia presented with mixed viral retinitis (cytomegalovirus and varicella zoster virus) post allogenic transplant. This presentation occurred despite ongoing prophylaxis for both of these viruses, as well as following two courses of treatment for CMV viremia, with a documented negative CMV PCR in the blood prior to the presentation with retinitis. The patient was treated with intravenous Ganciclovir and subsequently transitioned to oral Valganciclovir with resolution of the retinitis.
Conclusions: We report a rare case of polyviral retinitis in a post-allogeneic stem cell transplant patient, with polymerase chain reaction of the aqueous fluid demonstrating two viral populations. With very little existing literature on either mixed viral retinitis or CMV retinitis during Letermovir prophylaxis, this case expands the literature on both topics.