SpringerLink
Log in

Adult-onset of mild encephalitis/encephalopathy with reversible splenial lesion (MERS): case report and systematic review

  • Review Article
  • Published:
Neurological Sciences Aims and scope Submit manuscript

Abstract

Background

Mild encephalitis/encephalopathy with reversible splenial lesion (MERS) is a clinical-radiological syndrome characterized by transient central nervous system symptoms and a reversible lesion in the splenium of the corpus callosum (SCC) on magnetic resonance (MR). We reported a case of adult-onset MERS with uncommon presentation and reviewed the existing literature.

Methods

We described a case of adult-onset MERS with uncommon symptoms and signs and performed a systematic review of case series including more than four patients of adult-onset (> 14 years old) MERS, from January 2000 to December 2022. We summarized the clinical, laboratory, imaging and therapy data.

Results

We included seven eligible studies for a total of 51 adult-onset MERS patients. Neurological manifestations were preceded by prodromal symptoms in most of the patients (88%), mainly with fever (78%). Headache was the most common symptom (50%), followed by seizures (22%) and disturbance of consciousness (22%). Inflammatory changes on cerebrospinal fluid were present in a half of patient, so defining encephalitis cases. Clinal recovery, was achieved in all patients but two with severe disturbance of consciousness who required ventilator support in the acute phase. MR showed isolated lesion in the SCC in 92% of patients, while 8% of patients showed also extracallosal lesions, all the lesions resolved or improved on follow-up imaging.

Conclusions

MERS is a form of encephalitis/encephalopathy with a broad range of central nervous system manifestation, often with mild symptoms, such as headache alone, that can lead to overlooked some cases, with an excellent prognosis in most patient.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price includes VAT (Germany)

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2

Similar content being viewed by others

Data availability

Data supporting the results of the study are available upon reasonable request at the corresponding author.

References

  1. Tada H et al (2004) Clinically mild encephalitis/encephalopathy with a reversible splenial lesion. Neurology 63(10):1854–1858

    Article  CAS  PubMed  Google Scholar 

  2. Takanashi J (2009) Two newly proposed infectious encephalitis/encephalopathy syndromes. Brain Dev 31(7):521–528

    Article  PubMed  Google Scholar 

  3. Fang Q et al (2017) Clinically mild encephalitis/encephalopathy with a reversible splenial lesion of corpus callosum in Chinese children. Brain Dev 39(4):321–326

    Article  PubMed  Google Scholar 

  4. Chen WX et al (2016) Reversible splenial lesion syndrome in children: Retrospective study and summary of case series. Brain Dev 38(10):915–927

    Article  PubMed  Google Scholar 

  5. Hoshino A et al (2012) Epidemiology of acute encephalopathy in Japan, with emphasis on the association of viruses and syndromes. Brain Dev 34(5):337–343

    Article  PubMed  Google Scholar 

  6. Takanashi J et al (2006) Widening spectrum of a reversible splenial lesion with transiently reduced diffusion. AJNR Am J Neuroradiol 27(4):836–838

    CAS  PubMed  PubMed Central  Google Scholar 

  7. Takanashi J, Hirasawa K, Tada H (2006) Reversible restricted diffusion of entire corpus callosum. J Neurol Sci 247(1):101–104

    Article  PubMed  Google Scholar 

  8. Takanashi J et al (2010) Differences in the time course of splenial and white matter lesions in clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS). J Neurol Sci 292(1–2):24–27

    Article  PubMed  Google Scholar 

  9. Yuan J et al (2017) Mild encephalitis/encephalopathy with reversible splenial lesion (MERS) in adults-a case report and literature review. BMC Neurol 17(1):103

    Article  PubMed  PubMed Central  Google Scholar 

  10. Thabet M et al (2022) Rituximab-induced mild encephalopathy with a reversible splenial lesion syndrome (MERS): An adverse effect to add to the list. Br J Clin Pharmacol 88(6):2969–2972

    Article  CAS  PubMed  Google Scholar 

  11. Heraud C et al (2022) Glial Fibrillary Acidic Protein (GFAP) Astrocytopathy Presenting as Mild Encephalopathy with Reversible Splenium Lesion. Neurol Ther 11(1):499–505

    Article  PubMed  Google Scholar 

  12. Saghir K., et al (2022) Anti-MDA5 antibody-positive dermatomyositis with mild encephalopathy with reversible splenial lesion: a possible rare association? Wien Med Wochenschr, 1–4

  13. Mogi T et al (2017) Clinically mild encephalopathy with a reversible splenial lesion and nonconvulsive status epilepticus in a schizophrenic patient with neuroleptic malignant syndrome. Psychiatry Clin Neurosci 71(3):212

    Article  PubMed  Google Scholar 

  14. Ono R, Nishiguchi S, Kitagawa I (2022) Lithium intoxication-associated mild encephalitis/encephalopathy with a reversible splenial lesion: A case report. Bipolar Disord 24(5):551–552

    Article  PubMed  Google Scholar 

  15. Mawatari M et al (2018) Mild encephalitis/encephalopathy with a reversible splenial lesion due to Plasmodium falciparum malaria: a case report. Trop Med Health 46:37

    Article  PubMed  PubMed Central  Google Scholar 

  16. Chopra P, Bhatia RS, Chopra R (2019) Mild Encephalopathy/Encephalitis with Reversible Splenial Lesion in a Patient with Salmonella typhi Infection: An Unusual Presentation with Excellent Prognosis. Indian J Crit Care Med 23(12):584–586

    Article  PubMed  PubMed Central  Google Scholar 

  17. Nagpal K et al (2017) Chikungunya infection presenting as mild encephalitis with a reversible lesion in the splenium: a case report. J Neurovirol 23(3):501–503

    Article  PubMed  Google Scholar 

  18. Fu ML, Han N, Wang W (2021) Cytomegalovirus-Associated Mild Encephalopathy/Encephalitis With Reversible Splenial Lesion. Neurologist 26(5):172–174

    Article  PubMed  Google Scholar 

  19. Takahashi I, Yano H, Kinjo M (2020) Mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) following influenza virus infection. BMJ Case Rep. 13(5):e235461

    Article  PubMed  PubMed Central  Google Scholar 

  20. Zhang X et al (2020) Reversible splenial lesion syndrome in children: clinical analysis and summary of a case series. J Int Med Res 48(4):300060520914202

    Article  PubMed  Google Scholar 

  21. Yildiz AE et al (2018) Mild encephalitis/encephalopathy with a reversible splenial lesion in children. Diagn Interv Radiol 24(2):108–112

    PubMed  PubMed Central  Google Scholar 

  22. Hayashi M et al (2020) COVID-19-associated mild encephalitis/encephalopathy with a reversible splenial lesion. J Neurol Sci 415:116941

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. De Oliveira FA, De Melo TF, Rocha-Filho PA (2020) Transient lesion in the splenium of the corpus callosum associated with COVID-19. Arq Neuropsiquiatr 78(11):738

    Article  PubMed  Google Scholar 

  24. Liberati A et al (2009) The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. PLoS Med 6(7):e1000100

    Article  PubMed  PubMed Central  Google Scholar 

  25. Pan JJ et al (2015) Mild encephalitis/encephalopathy with a reversible splenial lesion: five cases and a literature review. Neurol Sci 36(11):2043–2051

    Article  PubMed  Google Scholar 

  26. Zhu Y et al (2016) Reversible splenial lesion syndrome associated with encephalitis/encephalopathy presenting with great clinical heterogeneity. BMC Neurol 16:49

    Article  PubMed  PubMed Central  Google Scholar 

  27. Zhang Z et al (2020) Mild Encephalitis/Encephalopathy with a Reversible Isolated Splenial Lesion (MERS) in Adult Patients: A Small Case Series. Eur Neurol 83(3):279–286

    Article  CAS  PubMed  Google Scholar 

  28. Grosset L et al (2021) Mild encephalopathy with reversible splenial lesion: Description of nine cases and review of the literature. Seizure 88:83–86

    Article  PubMed  Google Scholar 

  29. Gao X et al (2020) Clinical analysis of reversible splenial lesion syndrome in Chinese adults: A retrospective study of 11 cases. Medicine (Baltimore) 99(36):e22052

    Article  PubMed  Google Scholar 

  30. Xu W et al (2019) Clinical and Magnetic Resonance Imaging Features of Reversible Splenial Lesion Syndrome in Adults: A Small Case Series. Eur Neurol 82(4–6):86–92

    Article  CAS  PubMed  Google Scholar 

  31. Garcia-Monco JC et al (2011) Reversible splenial lesion syndrome (RESLES): what’s in a name? J Neuroimaging 21(2):e1-14

    Article  PubMed  Google Scholar 

  32. Kim SS et al (1999) Focal lesion in the splenium of the corpus callosum in epileptic patients: antiepileptic drug toxicity? AJNR Am J Neuroradiol 20(1):125–129

    CAS  PubMed  Google Scholar 

  33. Maeda M et al (2003) Transient splenial lesion of the corpus callosum associated with antiepileptic drugs: evaluation by diffusion-weighted MR imaging. Eur Radiol 13(8):1902–1906

    Article  PubMed  Google Scholar 

  34. Mirsattari SM et al (2003) Transient lesion in the splenium of the corpus callosum in an epileptic patient. Neurology 60(11):1838–1841

    Article  PubMed  Google Scholar 

  35. Tascilar N et al (2009) Unusual combination of reversible splenial lesion and meningitis-retention syndrome in aseptic meningomyelitis. Clinics (Sao Paulo) 64(9):932–937

    Article  PubMed  Google Scholar 

  36. Kitami M et al (2011) Acute urinary retention in a 23-year-old woman with mild encephalopathy with a reversible splenial lesion: a case report. J Med Case Rep 5:159

    Article  PubMed  PubMed Central  Google Scholar 

  37. Hidaka M et al (2021) (2021) Meningitis retention syndrome associated with complicated mild encephalitis/encephalopathy with reversible splenial lesion in a young adult patient: a case report. Oxf Med Case Reports 10:omab092

    Article  Google Scholar 

  38. Mizuguchi M et al (2021) Guidelines for the diagnosis and treatment of acute encephalopathy in childhood. Brain Dev 43(1):2–31

    Article  PubMed  Google Scholar 

  39. Ka A et al (2015) Mild encephalopathy with reversible splenial lesion: an important differential of encephalitis. Eur J Paediatr Neurol 19(3):377–382

    Article  PubMed  Google Scholar 

  40. Takanashi J et al (2009) Encephalopathy with a reversible splenial lesion is associated with hyponatremia. Brain Dev 31(3):217–220

    Article  PubMed  Google Scholar 

  41. Kashiwagi M et al (2014) Clinico-radiological spectrum of reversible splenial lesions in children. Brain Dev 36(4):330–336

    Article  PubMed  Google Scholar 

  42. Tetsuka S (2019) Reversible lesion in the splenium of the corpus callosum. Brain Behav 9(11):e01440

    Article  PubMed  PubMed Central  Google Scholar 

  43. Kakou M, Velut S, Destrieux C (1998) Arterial and venous vascularization of the corpus callosum. Neurochirurgie 44(1 Suppl):31–37

    CAS  PubMed  Google Scholar 

  44. Kahilogullari G et al (2013) Arterial vascularization patterns of the splenium: An anatomical study. Clin Anat 26(6):675–681

    Article  CAS  PubMed  Google Scholar 

  45. Hassel B et al (2003) Glutamate transport, glutamine synthetase and phosphate-activated glutaminase in rat CNS white matter. A quantitative study J Neurochem 87(1):230–237

    Article  CAS  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Neurology Unit, Nuovo Ospedale Santo Stefano, Prato, Italy

    Rinaldi Chiara

  2. Stroke Unit, AOU Careggi, Florence, Italy

    Palumbo Vanessa & Arba Francesco

  3. Department of Critical Care Medicine and Surgery, Careggi University Hospital, Florence, Italy

    Peyman Nazerian & Viviani Gabriele

  4. NEUROFARBA Department, University of Florence, Florence, Italy

    Farina Antonio & Massacesi Luca

  5. Department of Neurology 2, AOU Careggi, Florence, Italy

    Farina Antonio & Massacesi Luca

Authors
  1. Rinaldi Chiara
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Palumbo Vanessa
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Peyman Nazerian
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Viviani Gabriele
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Farina Antonio
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Massacesi Luca
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Arba Francesco
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Rinaldi Chiara.

Ethics declarations

All authors read and approved the manuscript, and the manuscript has not been submitted elsewhere nor published elsewhere in whole or in part.

Conflict of interest

All authors declare that they have no conflicts of interest. 

Ethical approval

Given the nature of the article, a case report and systematic review, no ethical approval was required.

Informed consent

Written informed consent was obtained from the participant of the study.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Chiara, R., Vanessa, P., Nazerian, P. et al. Adult-onset of mild encephalitis/encephalopathy with reversible splenial lesion (MERS): case report and systematic review. Neurol Sci (2024). https://doi.org/10.1007/s10072-024-07627-0

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s10072-024-07627-0

Keywords

Search

Navigation