title: Neuroanatomical correlates of stroke-associated infection and stroke-induced immunodepression.
abstract: BACKGROUND
  Infections represent the most frequent medical complications in stroke patients. Their main determinants are dysphagia and a transient state of immunodepression. We analyzed whether distinct anatomical brain regions were associated with the occurrence of stroke-associated infections or immunodepression.
  
  
  METHODS
  In 106 patients with acute ischemic stroke, we evaluated the incidence of pneumonia, urinary tract infection, or other infections together with the characterization of biomarkers of immunodepression. Twenty control subjects served to provide reference values. Using voxel-based lesion-symptom mapping, the involvement of gray and white matter structures was correlated with clinical and laboratory findings in crude analyses and in volume adjusted models to rule out associations reflecting differences in the size of the infarction.
  
  
  RESULTS
  Stroke-associated infection occurred in 22 (21%) patients and prevailed in patients with larger infarcts. Volume adjusted voxel-based lesion-symptom mapping revealed the involvement of the superior and middle temporal gyri, the orbitofrontal cortex, the superior longitudinal fasciculus and the inferior fronto-occipital fasciculus amongst infected patients. These associations were similar for pneumonia but not for urinary tract infections. Lymphopenia was associated with lesions of the superior and middle temporal gyri. Laterality did not influence stroke-associated infections or the presence of immunodepressive traits after volume control. The greatest overlap in the neuroanatomical correlates occurred between pneumonia and dysphagia.
  
  
  CONCLUSIONS
  Infarct volume plays a relevant role in the occurrence of stroke-associated infections, but lesions in specific brain locations such as the superior and lateral temporal lobe and the orbitofrontal cortex are also associated with increased infectious risk, especially pneumonia.
authors.affiliation: Functional Unit of Cerebrovascular Diseases, Hospital Clinic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain. Electronic address: xurra@clinic.cat.
authors.forename: Xabier
authors.initials: X
authors.lastname: Urra
authors.affiliation: Functional Unit of Cerebrovascular Diseases, Hospital Clinic, Barcelona, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Laredo
authors.affiliation: Functional Unit of Cerebrovascular Diseases, Hospital Clinic, Barcelona, Spain.
authors.forename: Yashu
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Functional Unit of Cerebrovascular Diseases, Hospital Clinic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Amaro
authors.affiliation: Functional Unit of Cerebrovascular Diseases, Hospital Clinic, Barcelona, Spain.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Rudilosso
authors.affiliation: Functional Unit of Cerebrovascular Diseases, Hospital Clinic, Barcelona, Spain.
authors.forename: Arturo
authors.initials: A
authors.lastname: Renú
authors.affiliation: Laboratory of Surgical NeuroAnatomy, School of Medicine, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Prats-Galino
authors.affiliation: Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas, Barcelona, Spain.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Planas
authors.affiliation: Functional Unit of Cerebrovascular Diseases, Hospital Clinic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Oleaga
authors.affiliation: Functional Unit of Cerebrovascular Diseases, Hospital Clinic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain; Medicine Department, School of Medicine, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Ángel
authors.initials: Á
authors.lastname: Chamorro
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007108:Immune Tolerance / Q000276:immunology*; D007165:Immunosuppression Therapy / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D020521:Stroke / Q000150:complications / Q000473:pathology*
keywords: Immunodepression; MRI; Stroke; Stroke-associated infection; Voxel-based lesion-symptom mapping