title: Chronic diarrhea associated with persistent norovirus excretion in patients with chronic lymphocytic leukemia: report of two cases.
abstract: BACKGROUND
  Chronic diarrhea in patients treated with immunosuppressive agents or suffering from immunosuppressive disease can represent a diagnostic and therapeutic challenge to the clinician. Norovirus infection, a major cause of acute epidemic diarrhea, has been described as a cause of chronic diarrhea in patients who are immunosuppressed, including transplant recipients and the very young.
  
  
  METHODS
  We describe two patients, a 64 year-old man and a 59 year-old woman, both suffering from chronic lymphocytic leukemia and hypogammaglobulinemia, who developed chronic diarrhea resistant to therapy. In both cases, after months of symptoms, persistent norovirus infection--documented by repeatedly-positive high-sensitivity stool enzyme immunoassay--was found to be the cause. Both patients died with active diarrheal symptoms.
  
  
  CONCLUSIONS
  We describe the first cases of advanced chronic lymphocytic leukemia to suffer from chronic symptomatic norovirus infection. Clinicians caring for such patients, particularly those with concomitant hypogammaglobulinema, who have chronic unexplained diarrhea, should consider norovirus infection in the differential diagnosis.
authors.affiliation: Baystate Regional Cancer Program/Tufts University School of Medicine, Springfield, MA 01107, USA.
authors.forename: Todd
authors.initials: T
authors.lastname: Capizzi
authors.forename: Grace
authors.initials: G
authors.lastname: Makari-Judson
authors.forename: Richard
authors.initials: R
authors.lastname: Steingart
authors.forename: Wilson C
authors.initials: WC
authors.lastname: Mertens
mesh_terms: D003967:Diarrhea / Q000209:etiology / Q000276:immunology / Q000821:virology*; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000627:therapeutic use; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000150:complications* / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D029322:Norovirus / Q000302:isolation & purification / Q000502:physiology*; D017201:Virus Shedding
chemical_list: D007166:Immunosuppressive Agents