Primary cytomegalovirus infection in immunocompetent adults in the United States - A case series.

Primary Cytomegalovirus (CMV) infection is often not suspected as a cause of fever of unknown origin (FUO) in immune-competent adults. We present a case-series of symptomatic primary CMV infection in immunocompetent adults presenting as fever of unknown origin (FUO). All patients with CMV serology tested between November 2008 and June 2016 underwent chart review. Cases were defined as those between 18 and 65 years of age with documented fever and elevated serum anti-CMV IgM. Exclusion criteria were organ specific CMV disease, positive serum anti-EBV IgM, or presence of any immunocompromising condition. Sixteen patients (69% male, mean age 42.2 ± 11.7 years) met criteria. Mean duration of illness was 4.6 ± 3.3 weeks. Common symptoms other than fever included fatigue (94%), night sweats (81%), malaise (75%), myalgias (63%), and headache (56%). Eleven patients (68.8%) had contact with young children; six (35.3%) patients had children in daycare. Twelve (75%) patients had extensive testing and multiple visits or hospitalizations prior to consulting with an infectious disease specialist. Peripheral smear was done in twelve (75%) patients and all had atypical lymphocytes. Five patients (31.3%) had a leukocytosis. Peak serum transaminases were: AST 115.25 ± 50.5 IU/L and ALT 168.38 ± 92.0 IU/L. One patient had splenic infarcts. In addition, two cases of hydrops fetalis were attributed to primary CMV infection. In summary, primary CMV infection can present as FUO in immunocompetent adults. Contact with young children in daycare may be a risk factor. Heightened clinical suspicion will promote earlier diagnosis and avoid unnecessary testing.