Stroke Severity, and Not Cerebral Infarct Location, Increases the Risk of Infection

  • Raymond Shim
  • Shu Wen Wen
  • Brooke J. Wanrooy
  • Michelle Rank
  • Tharani Thirugnanachandran
  • Luke Ho
  • Tara Sepehrizadeh
  • Michael de Veer
  • Velandai K. Srikanth
  • Henry Ma
  • Thanh G. Phan
  • Christopher G. Sobey
  • Connie H. Y. WongEmail author
Original Article


Infection is a leading cause of death in patients with stroke; however, the impact of cerebral infarct size or location on infectious outcome is unclear. To examine the effect of infarct size on post-stroke infection, we utilised the intraluminal middle-cerebral artery occlusion (MCAO) mouse model of ischemic stroke and adjusted the duration of arterial occlusion. At 1 day following stroke onset, the proportion of mice with infection was significantly greater in mice that had larger infarct sizes. Additionally, the presence of lung infection in these mice with severe strokes extended past 2 days, suggestive of long-term immune impairment. At the acute phase, our data demonstrated an inverse relationship between infarct volume and the number of circulating leukocytes, indicating the elevated risk of infection in more severe stroke is associated with reduced cellularity in peripheral blood, owing predominately to markedly decreased lymphocyte numbers. In addition, the stroke-induced reduction of lymphocyte-to-neutrophil ratio was also evident in the lung of all post-stroke animals. To investigate the effect of infarct location on post-stroke infection, we additionally performed a photothrombotic (PT) model of stroke and using an innovative systematic approach of analysis, we found the location of cerebral infarct does not impact on the susceptibility of post-stroke infection, confirming the greater role of infarct volume over infarct location in the susceptibility to infection. Our experimental findings were validated in a clinical setting and reinforced that stroke severity, and not infarct location, influences the risk of infection after stroke.


Stroke Infection Infarct volume Infarct location 



The authors acknowledge the facilities and scientific and technical assistance of the National Imaging Facility, a National Collaborative Research Infrastructure Strategy (NCRIS) capability, at the Monash Biomedical Imaging, Monash University. The authors acknowledge the facilities and technical assistance of Monash Histology Platform, at the Department of Anatomy and Developmental Biology, Monash University.

Funding Information

This work is supported by the National Heart Foundation (NHF, Australia; 100,863), CSL Centenary Fellowship and the National Health and Medical Research Council (NHMRC, Australia: APP1104036). The financial supports have no role in conducting the research and/or preparation of the article.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Supplementary material

12975_2019_738_MOESM1_ESM.docx (83 kb)
ESM 1 (DOCX 83 kb)


  1. 1.
    Heuschmann PU, Kolominsky-Rabas PL, Misselwitz B, Hermanek P, Leffmann C, Janzen R, et al. Predictors of in-hospital mortality and attributable risks of death after ischemic stroke: the German Stroke Registers Study Group. Arch Intern Med. 2004;164(16):1761–8.PubMedCrossRefPubMedCentralGoogle Scholar
  2. 2.
    Langhorne P, Stott D, Robertson L, MacDonald J, Jones L, McAlpine C, et al. Medical complications after stroke a multicenter study. Stroke. 2000;31(6):1223–9.PubMedCrossRefPubMedCentralGoogle Scholar
  3. 3.
    Vermeij FH, op Reimer WJS, De Man P, Van Oostenbrugge RJ, Franke CL, De Jong G, et al. Stroke-associated infection is an independent risk factor for poor outcome after acute ischemic stroke: data from the Netherlands Stroke Survey. Cerebrovasc Dis. 2009;27(5):465–71.PubMedCrossRefPubMedCentralGoogle Scholar
  4. 4.
    Hetze S, Engel O, Römer C, Mueller S, Dirnagl U, Meisel C, et al. Superiority of preventive antibiotic treatment compared with standard treatment of poststroke pneumonia in experimental stroke: a bed to bench approach. J Cereb Blood Flow Metab. 2013;33(6):846–54.PubMedPubMedCentralCrossRefGoogle Scholar
  5. 5.
    Kalra L, Irshad S, Hodsoll J, Simpson M, Gulliford M, Smithard D, et al. Prophylactic antibiotics after acute stroke for reducing pneumonia in patients with dysphagia (STROKE-INF): a prospective, cluster-randomised, open-label, masked endpoint, controlled clinical trial. Lancet. 2015;386(10006):1835–44.PubMedCrossRefPubMedCentralGoogle Scholar
  6. 6.
    Westendorp WF, Vermeij J-D, Zock E, Hooijenga IJ, Kruyt ND, Bosboom HJ, et al. The Preventive Antibiotics in Stroke Study (PASS): a pragmatic randomised open-label masked endpoint clinical trial. Lancet. 2015;385:1519–26.PubMedCrossRefPubMedCentralGoogle Scholar
  7. 7.
    Ulm L, Hoffmann S, Nabavi D, Hermans M, Mackert B-M, Hamilton F, et al. The randomized controlled STraWinSKi trial: procalcitonin-guided antibiotic therapy after stroke. Front Neurol. 2017;8.Google Scholar
  8. 8.
    van de Beek D, Wijdicks EF, Vermeij FH, de Haan RJ, Prins JM, Spanjaard L, et al. Preventive antibiotics for infections in acute stroke: a systematic review and meta-analysis. Arch Neurol. 2009;66(9):1076–81.PubMedPubMedCentralGoogle Scholar
  9. 9.
    Vermeij JD, Westendorp WF, Dippel DW, van de Beek D, Nederkoorn PJ. Antibiotic therapy for preventing infections in people with acute stroke. Cochrane Database Syst Rev. 2018;1:CD008530. Scholar
  10. 10.
    Offner H, Subramanian S, Parker SM, Wang C, Afentoulis ME, Lewis A, et al. Splenic atrophy in experimental stroke is accompanied by increased regulatory T cells and circulating macrophages. J Immunol. 2006;176(11):6523–31.PubMedCrossRefPubMedCentralGoogle Scholar
  11. 11.
    Prass K, Meisel C, Höflich C, Braun J, Halle E, Wolf T, et al. Stroke-induced immunodeficiency promotes spontaneous bacterial infections and is mediated by sympathetic activation reversal by poststroke T helper cell type 1–like immunostimulation. J Exp Med. 2003;198(5):725–36.PubMedPubMedCentralCrossRefGoogle Scholar
  12. 12.
    Wong CH, Jenne CN, Tam PP, Léger C, Venegas A, Ryckborst K, et al. Prolonged activation of invariant natural killer T cells and TH2-skewed immunity in stroke patients. Front Neurol. 2017;8.Google Scholar
  13. 13.
    Hug A, Liesz A, Muerle B, Zhou W, Ehrenheim J, Lorenz A, et al. Reduced efficacy of circulating costimulatory cells after focal cerebral ischemia. Stroke. 2011;42(12):3580–6.PubMedCrossRefPubMedCentralGoogle Scholar
  14. 14.
    Mracsko E, Liesz A, Karcher S, Zorn M, Bari F, Veltkamp R. Differential effects of sympathetic nervous system and hypothalamic–pituitary–adrenal axis on systemic immune cells after severe experimental stroke. Brain Behav Immun. 2014;41:200–9.PubMedCrossRefPubMedCentralGoogle Scholar
  15. 15.
    Haeusler KG, Schmidt WU, Föhring F, Meisel C, Helms T, Jungehulsing GJ, et al. Cellular immunodepression preceding infectious complications after acute ischemic stroke in humans. Cerebrovasc Dis. 2008;25(1–2):50–8.PubMedCrossRefPubMedCentralGoogle Scholar
  16. 16.
    Hug A, Dalpke A, Wieczorek N, Giese T, Lorenz A, Auffarth G, et al. Infarct volume is a major determiner of post-stroke immune cell function and susceptibility to infection. Stroke. 2009;40(10):3226–32.PubMedCrossRefPubMedCentralGoogle Scholar
  17. 17.
    Urra X, Laredo C, Zhao Y, Amaro S, Rudilosso S, Renú A, et al. Neuroanatomical correlates of stroke-associated infection and stroke-induced immunodepression. Brain Behav Immun. 2017;60:142–50.PubMedCrossRefPubMedCentralGoogle Scholar
  18. 18.
    Broadley S, Croser D, Cottrell J, Creevy M, Teo E, Yiu D, et al. Predictors of prolonged dysphagia following acute stroke. J Clin Neurosci. 2003;10(3):300–5.PubMedCrossRefPubMedCentralGoogle Scholar
  19. 19.
    Hoffmann S, Harms H, Ulm L, Nabavi DG, Mackert B-M, Schmehl I, et al. Stroke-induced immunodepression and dysphagia independently predict stroke-associated pneumonia–the PREDICT study. J Cereb Blood Flow Metab. 2017;37(12):3671–82.PubMedCrossRefPubMedCentralGoogle Scholar
  20. 20.
    Nakajoh K, Nakagawa T, Sekizawa K, Matsui T, Arai H, Sasaki H. Relation between incidence of pneumonia and protective reflexes in post-stroke patients with oral or tube feeding. J Intern Med. 2000;247(1):39–42.PubMedCrossRefPubMedCentralGoogle Scholar
  21. 21.
    Steinhagen V, Grossmann A, Benecke R, Walter U. Swallowing disturbance pattern relates to brain lesion location in acute stroke patients. Stroke. 2009;40(5):1903–6.PubMedCrossRefPubMedCentralGoogle Scholar
  22. 22.
    Harms H, Reimnitz P, Bohner G, Werich T, Klingebiel R, Meisel C, et al. Influence of stroke localization on autonomic activation, immunodepression, and post-stroke infection. Cerebrovasc Dis. 2011;32(6):552–60.PubMedCrossRefPubMedCentralGoogle Scholar
  23. 23.
    Sposato LA, Cohen G, Wardlaw JM, Sandercock P, Lindley RI, Hachinski V, et al. Effect of right insular involvement on death and functional outcome after acute ischemic stroke in the IST-3 trial (Third International Stroke Trial). Stroke. 2016;47(12):2959–65.PubMedCrossRefPubMedCentralGoogle Scholar
  24. 24.
    Walter U, Knoblich R, Steinhagen V, Donat M, Benecke R, Kloth A. Predictors of pneumonia in acute stroke patients admitted to a neurological intensive care unit. J Neurol. 2007;254(10):1323–9.PubMedCrossRefPubMedCentralGoogle Scholar
  25. 25.
    Phan TG, Donnan GA, Wright PM, Reutens DC. A digital map of middle cerebral artery infarcts associated with middle cerebral artery trunk and branch occlusion. Stroke. 2005;36(5):986–91.PubMedCrossRefPubMedCentralGoogle Scholar
  26. 26.
    Laredo C, Zhao Y, Rudilosso S, Renú A, Pariente JC, Chamorro Á, et al. Prognostic significance of infarct size and location: the case of insular stroke. Sci Rep. 2018;8(1):9498.PubMedPubMedCentralCrossRefGoogle Scholar
  27. 27.
    Minnerup J, Wersching H, Brokinkel B, Dziewas R, Heuschmann PU, Nabavi DG, et al. The impact of lesion location and lesion size on poststroke infection frequency. J Neurol Neurosurg Psychiatry. 2010;81(2):198–202.PubMedCrossRefPubMedCentralGoogle Scholar
  28. 28.
    Borsody M, Gargano JW, Reeves M, Jacobs B. Infarction involving the insula and risk of mortality after stroke. Cerebrovasc Dis. 2009;27(6):564–71.PubMedCrossRefPubMedCentralGoogle Scholar
  29. 29.
    Connolly ES, Winfree CJ, Stern DM, Stern DM, Solomon RA, Pinsky DJ. Procedural and strain-related variables significantly affect outcome in a murine model of focal cerebral ischemia. Neurosurgery. 1996;38(3):523–32.PubMedPubMedCentralGoogle Scholar
  30. 30.
    Paxinos G, Franklin KB. Paxinos and Franklin’s the mouse brain in stereotaxic coordinates: Academic Press; 2019.Google Scholar
  31. 31.
    Zhang SR, Piepke M, Chu HX, Broughton BR, Shim R, Wong CH, et al. IL-33 modulates inflammatory brain injury but exacerbates systemic immunosuppression following ischemic stroke. JCI Insight. 2018;3(18).Google Scholar
  32. 32.
    Phan TG, Kooblal T, Matley C, Singhal S, Clissold B, Ly J, et al. Stroke severity versus dysphagia screen as driver for post-stroke pneumonia. Front Neurol. 2019;10.Google Scholar
  33. 33.
    Friedman JH. Multivariate adaptive regression splines. Ann Stat. 1991;19(1):1–67.CrossRefGoogle Scholar
  34. 34.
    Chamorro Á, Urra X, Planas AM. Infection after acute ischemic stroke a manifestation of brain-induced immunodepression. Stroke. 2007;38(3):1097–103.PubMedCrossRefPubMedCentralGoogle Scholar
  35. 35.
    Curbelo J, Bueno SL, Galván-Román JM, Ortega-Gómez M, Rajas O, Fernández-Jiménez G, et al. Inflammation biomarkers in blood as mortality predictors in community-acquired pneumonia admitted patients: importance of comparison with neutrophil count percentage or neutrophil-lymphocyte ratio. PLoS One. 2017;12(3):e0173947.PubMedPubMedCentralCrossRefGoogle Scholar
  36. 36.
    de Jager CP, Wever PC, Gemen EF, Kusters R, van Gageldonk-Lafeber AB, van der Poll T, et al. The neutrophil-lymphocyte count ratio in patients with community-acquired pneumonia. PLoS One. 2012;7(10):e46561.PubMedPubMedCentralCrossRefGoogle Scholar
  37. 37.
    Nam K-W, Kim TJ, Lee JS, Kwon H-M, Lee Y-S, Ko S-B, et al. High neutrophil-to-lymphocyte ratio predicts stroke-associated pneumonia. Stroke. 2018;49(8):1886–92.PubMedCrossRefPubMedCentralGoogle Scholar
  38. 38.
    Longa EZ, Weinstein PR, Carlson S, Cummins R. Reversible middle cerebral artery occlusion without craniectomy in rats. Stroke. 1989;20(1):84–91.PubMedCrossRefPubMedCentralGoogle Scholar
  39. 39.
    Liesz A, Hagmann S, Zschoche C, Adamek J, Zhou W, Sun L, et al. The spectrum of systemic immune alterations after murine focal ischemia: immunodepression versus immunomodulation. Stroke. 2009;40(8):2849–58.PubMedCrossRefPubMedCentralGoogle Scholar
  40. 40.
    Nicholls AJ, Wen SW, Hall P, Hickey MJ, Wong CH. Activation of the sympathetic nervous system modulates neutrophil function. J Leukoc Biol. 2018;103(2):295–309.PubMedCrossRefPubMedCentralGoogle Scholar
  41. 41.
    Ruhnau J, Schulze K, Gaida B, Langner S, Kessler C, Bröker B, et al. Stroke alters respiratory burst in neutrophils and monocytes. Stroke. 2014;45(3):794–800.PubMedCrossRefPubMedCentralGoogle Scholar
  42. 42.
    Theodorou G, Marousi S, Ellul J, Mougiou A, Theodori E, Mouzaki A, et al. T helper 1 (Th1)/Th2 cytokine expression shift of peripheral blood CD4+ and CD8+ T cells in patients at the post-acute phase of stroke. Clin Exp Immunol. 2008;152(3):456–63.PubMedPubMedCentralCrossRefGoogle Scholar
  43. 43.
    Rohweder G, Salvesen Ø, Ellekjær H, Indredavik B. Hospital readmission within 10 years post stroke: frequency, type and timing. BMC Neurol. 2017;17(1):116.PubMedPubMedCentralCrossRefGoogle Scholar
  44. 44.
    Tziomalos K, Ntaios G, Miyakis S, Papanas N, Xanthis A, Agapakis D, et al. Prophylactic antibiotic treatment in severe acute ischemic stroke: the Antimicrobial chemopRrophylaxis for Ischemic STrokEIn MaceDonIa–Thrace Study (ARISTEIDIS). Intern Emerg Med. 2016;11(7):953–8.PubMedCrossRefPubMedCentralGoogle Scholar
  45. 45.
    Manwani B, Liu F, Xu Y, Persky R, Li J, McCullough LD. Functional recovery in aging mice after experimental stroke. Brain Behav Immun. 2011;25(8):1689–700.PubMedPubMedCentralCrossRefGoogle Scholar
  46. 46.
    Ritzel RM, Lai Y-J, Crapser JD, Patel AR, Schrecengost A, Grenier JM, et al. Aging alters the immunological response to ischemic stroke. Acta Neuropathol. 2018;136(1):89–110.PubMedPubMedCentralCrossRefGoogle Scholar
  47. 47.
    Yager JY, Wright S, Armstrong EA, Jahraus CM, Saucier DM. The influence of aging on recovery following ischemic brain damage. Behav Brain Res. 2006;173(2):171–80.PubMedCrossRefPubMedCentralGoogle Scholar
  48. 48.
    Licastro F, Candore G, Lio D, Porcellini E, Colonna-Romano G, Franceschi C, et al. Innate immunity and inflammation in ageing: a key for understanding age-related diseases. Immun Ageing. 2005;2(1):8.PubMedPubMedCentralCrossRefGoogle Scholar
  49. 49.
    Wen SW, Wong CH. Aging-and vascular-related pathologies. Microcirculation. 2019;26(2):e12463.PubMedCrossRefPubMedCentralGoogle Scholar
  50. 50.
    Stanley D, Mason LJ, Mackin KE, Srikhanta YN, Lyras D, Prakash MD, et al. Translocation and dissemination of commensal bacteria in post-stroke infection. Nat Med. 2016;22(11):1277–84.PubMedCrossRefPubMedCentralGoogle Scholar
  51. 51.
    Wen SW, Shim R, Ho L, Wanrooy BJ, Srikhanta YN, Prame Kumar K, et al. Advanced age promotes colonic dysfunction and gut-derived lung infection after stroke. Aging Cell. 2019:e12980.Google Scholar
  52. 52.
    Kemmling A, Lev MH, Payabvash S, Betensky RA, Qian J, Masrur S, et al. Hospital acquired pneumonia is linked to right hemispheric peri-insular stroke. PLoS One. 2013;8(8):e71141.PubMedPubMedCentralCrossRefGoogle Scholar
  53. 53.
    Walter U, Kolbaske S, Patejdl R, Steinhagen V, Abu-Mugheisib M, Grossmann A, et al. Insular stroke is associated with acute sympathetic hyperactivation and immunodepression. Eur J Neurol. 2013;20(1):153–9.PubMedCrossRefPubMedCentralGoogle Scholar
  54. 54.
    Kodumuri N, Sebastian R, Davis C, Posner J, Kim EH, Tippett DC, et al. The association of insular stroke with lesion volume. Neuroimage Clin. 2016;11:41–5.PubMedPubMedCentralCrossRefGoogle Scholar
  55. 55.
    Türe U, Yaşargil MG, Al-Mefty O, Yaşargil DC. Arteries of the insula. J Neurosurg. 2000;92(4):676–87.PubMedCrossRefPubMedCentralGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Raymond Shim
    • 1
  • Shu Wen Wen
    • 1
  • Brooke J. Wanrooy
    • 1
  • Michelle Rank
    • 2
    • 3
  • Tharani Thirugnanachandran
    • 4
  • Luke Ho
    • 1
    • 5
  • Tara Sepehrizadeh
    • 6
  • Michael de Veer
    • 6
  • Velandai K. Srikanth
    • 5
  • Henry Ma
    • 4
  • Thanh G. Phan
    • 4
  • Christopher G. Sobey
    • 7
  • Connie H. Y. Wong
    • 1
    Email author
  1. 1.Centre for Inflammatory Diseases, Department of Medicine at Monash Health, School of Clinical Sciences, Monash Medical CentreMonash UniversityClaytonAustralia
  2. 2.Department of Anatomy and Neuroscience, School of Biomedical SciencesThe University of MelbourneParkvilleAustralia
  3. 3.School of Health and Biomedical SciencesRMIT UniversityBundooraAustralia
  4. 4.Stroke and Ageing Research Group, Department of Medicine at Monash Health, School of Clinical Sciences, Monash Medical CentreMonash UniversityClaytonAustralia
  5. 5.Department of Medicine (Academic Unit), Peninsula Clinical School, Central Clinical SchoolMonash UniversityFrankstonAustralia
  6. 6.Monash Biomedical ImagingMonash UniversityClaytonAustralia
  7. 7.Department of Physiology, Anatomy and Microbiology, School of Life SciencesLa Trobe UniversityBundooraAustralia

Personalised recommendations