“Stealth mode”: cytomegalovirus in unlikely hosts—a report of two cases

Cytomegalovirus (CMV) infection is asymptomatic in healthy individuals but can cause life-threatening infections in immunocompromised patients.CMV disease in the non-transplant setting is very rare.Owing to the high seroprevalence of CMV infection, routine screening is not recommended; however, CMV should be considered as a diagnosis of exclusion in non-transplant immunocompromised patients who present with multisystem involvement and refractory cytopenia.In this case series, we describe two patientsone with B-cell acute lymphoblastic leukemia and the other with Langerhans cell histiocytosis-both complicated by CMV infection, underscoring the importance of considering CMV infection in the differential diagnosis.