title: Young male patients are at elevated risk of developing serious central nervous system complications during acute Puumala hantavirus infection.
abstract: BACKGROUND
  Our aim was to characterize clinical properties and laboratory parameters in patients with or without cerebrospinal fluid (CSF) findings suggestive of central nervous system (CNS) involvement, and especially those who developed serious CNS complications during acute nephropathia epidemica (NE) caused by Puumala hantavirus (PUUV) infection.
  
  
  METHODS
  A prospective cohort of 40 patients with acute NE and no signs of major CNS complications was analyzed. In addition, 8 patients with major CNS complications associated with NE were characterized. We collected data of CNS symptoms, CSF analysis, brain magnetic resonance imaging (MRI) results, electroencephalography (EEG) recordings, kidney function, and a number of laboratory parameters. Selected patients were evaluated by an ophthalmologist.
  
  
  RESULTS
  Patients with a positive CSF PUUV IgM finding or major CNS complications were more often males (p < 0.05) and they had higher plasma creatinine values (p < 0.001) compared to those with negative CSF PUUV IgM. The degree of tissue edema did not explain the CSF findings. Patients with major CNS complications were younger than those with negative CSF PUUV IgM finding (52.9 vs. 38.5 years, p < 0.05). Some patients developed permanent neurological and ophthalmological impairments.
  
  
  CONCLUSIONS
  CNS and ocular involvement during and after acute NE can cause permanent damage and these symptoms seem to be attributable to true infection of the CNS rather than increased tissue permeability. The possibility of this condition should be borne in mind especially in young male patients.
authors.affiliation: Department of Internal Medicine, Oulu University Hospital, Oulu, Finland. timo.hautala@oulu.fi
authors.forename: Timo
authors.initials: T
authors.lastname: Hautala
authors.forename: Nina
authors.initials: N
authors.lastname: Hautala
authors.forename: Saara-Mari
authors.initials: SM
authors.lastname: Mähönen
authors.forename: Tarja
authors.initials: T
authors.lastname: Sironen
authors.forename: Eija
authors.initials: E
authors.lastname: Pääkkö
authors.forename: Ari
authors.initials: A
authors.lastname: Karttunen
authors.forename: Pasi I
authors.initials: PI
authors.lastname: Salmela
authors.forename: Olli
authors.initials: O
authors.lastname: Vainio
authors.forename: Seppo
authors.initials: S
authors.lastname: Rytky
authors.forename: Alexander
authors.initials: A
authors.lastname: Plyusnin
authors.forename: Antti
authors.initials: A
authors.lastname: Vaheri
authors.forename: Olli
authors.initials: O
authors.lastname: Vapalahti
authors.forename: Heikki
authors.initials: H
authors.lastname: Kauma
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002493:Central Nervous System Diseases / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D015331:Cohort Studies; D005260:Female; D018778:Hantavirus Infections / Q000150:complications* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D029262:Puumala virus / Q000472:pathogenicity*; D012307:Risk Factors