62 year old male from Arizona was admitted at an outside hospital with a 3 week history of headaches, fever and arthralgias. Patient was exposed to desert flora and surrounded by wild life, but there is no history of overseas travel in several years. Physical exam was normal, except for fever of 100 – 101 F. Labs showed mildly elevated liver enzymes with a normal hepatitis profile. CT Head, lumbar puncture with CSF analysis and temporal arterial biopsy were all normal. CT Chest showed right lower lobe infiltrate. Ultrasound revealed splenomegaly. Patient was subsequently transferred to our hospital for further evaluation of fever of unknown origin (FUO). All antibiotics were discontinued and the fever pattern was closely monitored. Mild pericardial effusion was noted on echocardiogram. Repeat blood and urine cultures did not show any growth. Serum Immunoglobulins(Ig) G and M titers for toxoplasma, coxiella, anaplasma, ehrlichia, rickettsiae, west nile and epstein barr virus were all normal. Human immunodeficiency virus 1 and 2 antibodies, blood tuberculosis screen and fungal battery were negative. CMV DNA was detected by polymerase chain reaction, and both IgM and IgG antibody titers were elevated. CMV gene mutation studies were negative for ganciclovir resistance. The patient was severely symptomatic and was started on ganciclovir. With treatment he started feeling better but developed bone marrow toxicity. The absolute neutrophil count (ANC) decreased and ganciclovir had to be stopped after 5 days of therapy. Subsequently, CMV IgG avidity index, which was sent earlier, was low — 0.12, indicating recent infection. Patient’s ANC improved, he remained afebrile with resolution of symptoms and was discharged home.
Primary CMV infection in immunocompetent individuals is most often seen in young adults and less common latter in life. It is difficult to distinguish primary infection versus reactivation as CMV viral DNA and IgM and IgG antibodies can be present in both conditions. IgG avidity index is used to differentiate the two conditions and low avidity index makes primary infection most likely. Ganciclovir/valganciclovir is the drug of choice for treating CMV infection and myelosuppression is the principal dose‐limiting toxicity. Neutropenia occurs in 15‐40% of patients and thrombocytopenia in 5‐20%. It is usually reversible within 1 week of drug cessation however at times it can be fatal.
Evaluation of FUO with headache can be challenging and a broad differential diagnosis should always be entertained including CMV infection. IgG avidity index can be used to differentiate primary infection from reactivation of CMV. Antiviral therapy might be considered in select cases of severe primary CMV infection in immunocompetent individuals but ganciclovir can cause bone marrow toxicity, blood counts especially neutrophil and platelet count should be closely monitored.
To cite this abstract:Veeraraghavan G, Anumandla A, Gopireddy A. Headache and Fever of Unknown Origin — a Case of Primary Cytomegalovirus (Cmv) Infection. Abstract published at Hospital Medicine 2014, March 24-27, Las Vegas, Nev. Abstract 666. Journal of Hospital Medicine. 2014; 9 (suppl 2). https://www.shmabstracts.com/abstract/headache-and-fever-of-unknown-origin-a-case-of-primary-cytomegalovirus-cmv-infection/. Accessed September 16, 2019.