title: Diagnostic dilemma: Epstein-Barr virus (EBV) infectious mononucleosis with lung involvement or co-infection with Legionnaire's disease?
abstract: BACKGROUND
  Hospitalized adults with fever and "pneumonia" can be a difficult diagnostic challenge particularly when the clinical findings may be due to different infectious diseases.
  
  
  METHODS
  We recently had an elderly female who presented with fever, fatigue and dry cough with elevated serum transaminases and lung infiltrates. The diagnosis of Epstein-Barr virus (EBV) infectious mononucleosis (IM) was made based on a positive Monospot test, elevated EBV VCA IgM titer, and highly elevated EBV viral load. Her chest infiltrates were not accompanied by hilar adenopathy which may occur with EBV IM. Her dry cough persisted and she developed abdominal pain.
  
  
  RESULTS
  Legionnaire's disease was considered because she had extra-pulmonary findings characteristic of Legionnaire's disease, e.g., relative bradycardia, abdominal pain, hyponatremia, hypophosphatemia, elevated ferritin levels, microscopic hematuria. Legionella titers were negative, but Legionella (serogroup 1) urinary antigen was positive.
  
  
  CONCLUSIONS
  We present a diagnostic dilemma in an elderly female with both Legionnaire's disease and Epstein-Barr virus infectious mononucleosis with pulmonary involvement.
authors.affiliation: Infectious Disease Division, Winthrop-University Hospital, Mineola, NY, USA; State University of New York, School of Medicine, Stony Brook, NY, USA. Electronic address: bacunha@Winthrop.org.
authors.forename: Burke A
authors.initials: BA
authors.lastname: Cunha
authors.affiliation: Infectious Disease Division, Winthrop-University Hospital, Mineola, NY, USA; State University of New York, School of Medicine, Stony Brook, NY, USA.
authors.forename: John
authors.initials: J
authors.lastname: Gian
mesh_terms: D000368:Aged; D000914:Antibodies, Viral / Q000032:analysis*; D060085:Coinfection; D003937:Diagnosis, Differential; D005260:Female; D004854:Herpesvirus 4, Human / Q000276:immunology*; D006801:Humans; D007244:Infectious Mononucleosis / Q000175:diagnosis* / Q000821:virology; D007875:Legionella / Q000302:isolation & purification*; D007877:Legionnaires' Disease / Q000175:diagnosis* / Q000382:microbiology; D013902:Radiography, Thoracic
chemical_list: D000914:Antibodies, Viral
keywords: EBV infectious mononucleosis in the elderly; Ferritin levels; Hypophosphatemia; Laboratory abnormalities in Legionnaire's disease; Legionella; Microscopic hematuria; Pneumonia with nodular opacities; Pulmonary manifestations of EBV infectious mononucleosis; Relative bradycardia; co-infections