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Sudden bilateral blindness in Wernicke's encephalopathy: Case report and review of the literature
Journal of the Neurological Sciences 260 (2007) 261 – 264 www.elsevier.com/locate/jns
Short communication
Sudden bilateral blindness in Wernicke's encephalopathy: Case report and review of the literature Rainer Surges ⁎, Sandra Beck, Wolf-Dirk Niesen, Cornelius Weiller, Michel Rijntjes Department of Neurology, University of Freiburg, Breisacherstr, 64, 79106 Freiburg, Germany Received 5 February 2007; received in revised form 20 March 2007; accepted 3 April 2007 Available online 18 May 2007
Abstract We report on a patient suffering from bilateral sudden blindness as initial symptom of Wernicke's encephalopathy (WE). A 37-year-old male alcoholic was admitted to a psychiatric clinic because of excessive alcohol consumption (3.4‰). 24 h later he developed acute bilateral blindness with no light perception, downbeat nystagmus, bilateral ocular abduction deficits, cerebellar ataxia as well as a slight psychomotor slowing and mild disorientation. MRI including diffusion-weighted imaging and MR-angiography 3 h after symptom onset did not reveal findings suggestive for ischemic stroke. Immediate iv-application of thiamine led to a nearly complete remission of the neuroophthalmologic symptoms within 12 h. Although we critically discuss other potential etiologies, we conclude that the complex clinical picture with initial sudden blindness is an unusual presentation of WE. © 2007 Elsevier B.V. All rights reserved. Keywords: Wernicke's encephalopathy; Acute blindness; Downbeat nystagmus; Stroke; Alcohol; Diffusion-weighted imaging; Metabolic brain disease
1. Introduction
2. Case report
WE is caused by a thiamine deficit leading to disturbances in cerebral glucose metabolism. Typical early symptoms include oculomotor deficits (frequently bilateral abduction deficits due to VI nerve palsies, and vertical/horizontal nystagmus), ataxia and behavioural/mental disturbances [1]. To date, associated loss of vision has been reported in 8 cases only and mainly developed progressively over a couple of days or could be explained by papilledema or retinal hemorrhage [cf. Table 1, [2–8]]. In the present case bilateral blindness occurred suddenly without acute retinal affection and as an initial symptom. This sudden onset raises the question of other underlying etiologies, especially of brain ischemia, revealing the absence of highly sensitive diagnostic tools in WE and the presence of the diagnostic gap between transient ischemic attack and abnormalities in diffusion-weighted imaging (DWI) in MRI.
A 37-year old male with chronic alcohol abuse was admitted to a nearby psychiatric clinic due to alcohol intoxication (blood alcohol level 3.4‰). 24 h later he suffered from acute, stroke-like bilateral blindness with no light perception (“as if somebody has switched off the light”) and was referred to our centre within 2 h. His medical history comprised a perinatal neuroophthalmologic affection of unknown etiology with a residual scotoma within the temporal visual field on the right eye as well as a discrete esotropia (with deviation of the right bulbus). These neuroophthalmologic problems were stable over more than 30 years. There has been a history of heavy alcohol abuse and chronic tobacco abuse since several years. On admission, the malnourished patient (172 cm, 58 kg, body mass index 19.6 kg/m 2 ) was awake, oriented to time and person, co-operative without apparent mnestic deficits, but with a slight psychomotor slowing and disorientation to his own situation. He denied headache and had no history of migraine. The neuroophthalmologic picture was complex: he presented prominent esotropia
⁎ Corresponding author. Tel.: +49 761 2705296; fax: +49 761 2705310. E-mail address: [email protected] (R. Surges). 0022-510X/$ - see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.jns.2007.04.005
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R. Surges et al. / Journal of the Neurological Sciences 260 (2007) 261–264
Table 1 Review of visual loss during Wernicke's encephalopathy Ref. Age/ sex
Clinical course of visual loss
Neuroophthalmology
Acuity/funduscopy/ VEP (visually Presumed site of visual field evoked potentials) action (initial examination)
[2]
2 patients. Blindness on day 28/35 a, onset unclear, both patients died. Incomplete loss of vision. Onset and evolution not specified.
Nystagmus
–/Papilledema on day 21 + 28 a/–
[3]
20/F
[4]
40/ M
Progressive visual loss over a couple of days. Incomplete recovery within 3 months upon thiamine.
Horizontal/vertical gaze palsies; LR+
Perception of light only/ normal/–
Uncooperative patient
Cortical
[5]
64/F
Progressive visual loss over a couple of days. Substantial improvement within 1 month upon thiamine. Blindness, onset unclear. Recovery within 1 month upon thiamine. Progressive visual loss over 10 days to blindness. Substantial improvement within 24 h upon thiamine. Sudden onset blindness (no light perception). Recovery within a couple of days upon thiamine. Sudden onset blindness (no light perception). Recovery within 12 h upon thiamine.
Nystagmus upon horizontal gaze
–/normal/–
Flash VEP not reproducible
Unclear
[6] b 39/ M [7]
21/F
[8]
47/F
⁎
37/ M
Horizontal/vertical Reduced/ nystagmus; Horizontal/ papilledema + vertical gaze palsies peripapillary hemorrhage/–
Cranial imaging/MRI
MRI: symmetrical hyperintensities within the thalamus and midbrain (DWI, T2, FLAIR sequences) MRI: discrete white matter lesions and prominent bilateral hyperintensities in nucleus lentiformis (T2). SPECT: unilateral occipital hypoperfusion and bilaterally in thalamus and cerebellum. MRI: symmetrical hyperintensities within the thalamus, midbrain (T2, FLAIR)
Nystagmus
Horizontal/vertical nystagmus; Incomplete gaze palsies in all directions Vertical nystagmus on upgaze; Incomplete vertical/horizontal gaze palsies; Esotropia, LR-, Downbeat nystagmus; Esotropia (bilateral abduction deficits); Mydriasis, LR+
–/bilateral papilledema + retinal hemorrhages/–
–/atrophy of the right optic disc/–
MRI: normal
Pattern VEP pathologic
Optic nerves
Contrast enhanced CT: normal
Not adequately feasible
Cortical
MRI: normal
⁎: our patient. a Days after first and continued parenteral nutrition incidentally without thiamine. b Only abstract in English. LR: pupillary light reaction.
due to severe bilateral abduction defects, a spontaneous downbeat nystagmus and a mydriasis with positive, relatively slow pupillary light reaction. There was no light perception, the menace reflex (brusk hand movements in front of the patient) as well as the “mirror test” (mirror in front of the patient to test whether there is an ocular pursuit movement) were both negative, arguing against visual loss of non-organic origin. The patient additionally presented cerebellar ataxia with bilateral intention tremor on both arms and legs, whereas there was no tremor at rest. Clinical signs of polyneuropathy were completely absent, since all tendon reflexes (ankle jerks included) were brisk without Babinskis sign and sensation (vibration sensation in both arms and legs included) was entirely preserved. Blood
analysis yielded an elevated Gamma-GT (145 U/l; normal b 66 U/l) only. Other liver enzymes, cholinesterase and alcohol level were normal. Thiamine was not examined. ECG was normal. Blood pressure was in a range between 120–150/70–90 mm Hg during his stay in our hospital. Stroke-MRI within 3 h after symptom onset revealed no particularities (see Fig. 1). Since the symptoms were timely related to excessive alcohol consumption, 100 mg intravenous thiamine was rapidly applied and continued during the next days. Within 12 h, downbeat nystagmus as well as vision had completely recovered, the bilateral abduction deficits were markedly improved (a slight esotropia with deviation of the right eye known since childhood persisted). Ophthalmological examination the next day
R. Surges et al. / Journal of the Neurological Sciences 260 (2007) 261–264
263
Fig. 1. Cranial MRI. A: Axial DWI image without apparent diffusion deficits. B: “Time of Flight” angiography with normal flow signal in all cerebral arteries, especially the basilar artery (asterisk) and posterior cerebral artery (pca). C: Coronal FLAIR sequence that only showed artefacts due to movement. D: Axial T2 image without particularities.
revealed the known visual field defect on the right eye due to an atrophy of the optic disc but most importantly without papilledema or retinal hemorrhage. Due to developing delirium tremens with visual hallucinations after 24 h, visually evoked potentials and Goldman perimetry were not adequately feasible and the patient was re-referred to the psychiatric clinic. The intention tremor and ataxia persisted in a milder form for a further few days. On discharge some weeks later, the patient was completely independent and the neurological examination only yielded the known scotoma and the discrete esotropia. Unfortunately, further examinations (e.g. visually evoked potentials and additional ophthalmologic examination) were not done. 3. Discussion WE is clinically diagnosed, since there are no highly sensitive tools to prove this pathological entity. A low serum level of thiamine and a low erythrocyte transketolase
activity can support the diagnosis but lack sensitivity and may not be available immediately. Suggestive MRI findings (bilateral lesions around the third/fourth ventricle, in the medial parts of the thalamus, corpora mamillaria, mesencephalon, tegmentum and periaqueductal) can strengthen the diagnosis, but sensitivity only amounts to about 50% [9]. Newer works report on DWI abnormalities within the typical localization of WE-associated lesions that might precede lesions detected by other MRI sequences [3,10– 16]. In our patient DWI was performed 3 h after sudden symptom onset and was without particularities, whereas the earliest time scale reporting DWI abnormalities was 29 h so far [12]. The most interesting feature is the sudden bilateral blindness during the initial phase of the disease. Although there are various toxicologic and metabolic etiologies known to cause acute loss of vision [17], the most important differential diagnosis to be ruled out is a transient ischemic attack (TIA) in the vertebrobasilar territory. TIA cannot be excluded completely, due to a diagnostic and methodological gap between DWI abnormalities and the occurrence of
264
R. Surges et al. / Journal of the Neurological Sciences 260 (2007) 261–264
TIA: DWI abnormalities in TIA are reported in 35–44% only with an increasing probability of DWI abnormalities beyond 60 min [18,19]. In view of the normal Stroke-MRI 3 h after acute onset and still in the presence of the full clinical picture, the bilateral pattern of neurological symptoms (especially bilateral abduction deficits and the cerebellar ataxia, which does not fit a top of the basilar syndrome, but rather WE), and the fast clinical recovery following thiamine substitution within a clinical context of chronic alcohol abuse, we suggest an unusual presentation of WE. Thiamine pyrophosphate is an essential coenzyme for cerebral glucose metabolism and involved in the regulation of the osmotic gradient across the cell membranes. Functional loss of cortical cells during lack of thiamine is attributed to disturbances in metabolism of glucose, local accumulation of lactate, pyruvate and alanin leading to local acidosis [20] and extra-/intracellular edema that may lead to demyelinisation, glial proliferation, hemorrhagic lesions and necrosis at the WE-typical lesion sites [21]. Concerning the acute vision loss in our patient, the fast clinical recovery suggests a reversible metabolic dysfunction which is not necessarily detected by the recent DWI techniques, as outlined above. Because of the preserved pupillary light reaction and the absence of acute retinal damages we rather propose a cortical site of action, what has already been reported before [4]. In contrast, e.g. a nutritional (“tobacco–alcohol”) amblyopia is rather unprobable because of the preserved pupillary light reaction as well as the fast clinical onset and recovery. An episode of a relapsing chronic inflammatory demyelinating disease could be suggested by the residual atrophy of the optic disc, but the perinatal onset, the absence of clinical progression over more than 30 years and the recent MRI imaging argue against this hypothesis. 4. Conclusion In summary, we report an unusual presentation of WE with initial and sudden onset of bilateral blindness, oculomotor deficits, cerebellar ataxia and a slight psychomotor slowing in a young male alcoholic. Because of the diagnostic dilemma mentioned above, we suggest immediate application of thiamine as well as diagnostic work-up to detect ischemic strokes in rapidly evolving clinical pictures within the context of chronic alcohol abuse. Acknowledgement We thank PD Dr. Ansgar Berlis from the Section of Neuroradiology at the Department of Neurosurgery for providing us the MRI images.
References [1] Victor M, Adams RD, Collins OH. The Wernicke–Korsakoff syndrome and related disorders due to alcoholism and malnutrition. 2nd edition. Philadelphia: Davis; 1989. p. 1–117. [2] Bleggi-Torres LF, de Medeiros BC, Ogasawara VS, Loddo G, Zanis Neto J, Pasquini R, et al. Iatrogenic Wernicke's encephalopathy in allogeneic bone marrow transplantation: a study of eight cases. Bone Marrow Transplant 1997;20:391–5. [3] Halavaara J, Brander A, Lyytinen J, Setala K, Kallela M. Wernicke's encephalopathy: is diffusion-weighted MRI useful? Neuroradiology 2003;45:519–23. [4] Kraus J, Heckmann G, Sommer JB, Erbguth F, Platsch G, Neundörfer B. SPECT-Befunde bei Wernicke Encephalopathie. Aktuelle Neurol 2001;28:128–31. [5] Kuhn J, Friedel V, Knitelius O, Bewermeyer H. Iatrogenes Wernicke– Korsakoff-Syndrom mit ungewöhnlichen Symptomen und MRTVeränderungen. Nervenarzt 2004;75:795–800. [6] Miyashita H, Saitho T, Nakano N, Ishigaki H, Ikemoto M, Uthumi K, et al. A case of Wernicke's encephalopathy which accompanied a passing blindness. Arukoru Kenkyuto Yakubutsu Ison 1994;29:114–20. [7] Tesfaye S, Achari V, Yang YC, Harding S, Bowden A, Vora JP. Pregnant, vomiting and going blind. Lancet 1998;352:1594. [8] Timmings PL, Carroll GJ, Donaldson IM. Wernicke's encephalopathy presenting with blindness. N Z Med J 1993;106:159–60. [9] Antunez E, Estruch R, Cardenal C, Nicolas JM, Fernandez-Sola J, Urbano-Marquez A. Usefulness of CT and MR imaging in the diagnosis of acute Wernicke's encephalopathy. Am J Roentgenol 1998;171:1131–7. [10] Bergui M, Bradac GB, Zhong JJ, Barbero PA, Durelli L. Diffusionweighted MR in reversible Wernicke encephalopathy. Neuroradiology 2001;43:969–72. [11] Chu K, Kang DW, Kim HJ, Lee YS, Park SH. Diffusion-weighted imaging abnormalities in Wernicke encephalopathy: reversible cytotoxic edema? Arch Neurol 2002;59:123–7. [12] Doherty MJ, Watson NF, Uchino K, Hallam DK, Cramer SC. Diffusion abnormalities in patients with Wernicke encephalopathy. Neurology 2002;58:655–7. [13] Ducreux D, Petit-Lacour MC, Benoudiba F, Castelain V, MarsotDupuch K. Diffusion-weighted imaging in a case of Wernicke encephalopathy. J Neuroradiol 2002;29:39–42. [14] Hashimoto T, Ueda H, Mitui Y, Kihara M, Takahashi M, Kusunoki S. Diffusion-weighted magnetic resonance imaging findings at early stage of acute Wernicke encephalopathy. Rinsho Shinkeigaku 2004;44:422–6. [15] Hong KS, Kang DW, Cho YJ, Hwang YJ, Hur G. Diffusion-weighted magnetic resonance imaging in Wernicke's encephalopathy. Acta Neurol Scand 2002;105:132–4. [16] Unlu E, Cakir B, Asil T. MRI findings of Wernicke encephalopathy revisited due to hunger strike. Eur J Radiol 2006;57:43–53. [17] Purvin V, Kawasaki A. Neuro-ophthalmic emergencies for the neurologist. Neurologist 2005;11:195–233. [18] Inatomi Y, Kimura K, Yonehara T, Fujioka S, Uchino M. DWI abnormalities and clinical characteristics in TIA patients. Neurology 2004;62:376–80. [19] Lamy C, Oppenheim C, Calvet D, Domigo V, Naggara O, Meder JL, et al. Diffusion-weighted MR imaging in transient ischaemic attacks. Eur Radiol 2006;16:1090–5. [20] Hakim AM. The induction and reversibility of cerebral acidosis in thiamine deficiency. Ann Neurol 1984;16:673–9. [21] Harper CG. The incidence of Wernicke's encephalopathy in Australia: a neuropathological study of 131 cases. J Neurol Neurosurg Psychiatry 1983;46:519–23.
Short communication
Sudden bilateral blindness in Wernicke's encephalopathy: Case report and review of the literature Rainer Surges ⁎, Sandra Beck, Wolf-Dirk Niesen, Cornelius Weiller, Michel Rijntjes Department of Neurology, University of Freiburg, Breisacherstr, 64, 79106 Freiburg, Germany Received 5 February 2007; received in revised form 20 March 2007; accepted 3 April 2007 Available online 18 May 2007
Abstract We report on a patient suffering from bilateral sudden blindness as initial symptom of Wernicke's encephalopathy (WE). A 37-year-old male alcoholic was admitted to a psychiatric clinic because of excessive alcohol consumption (3.4‰). 24 h later he developed acute bilateral blindness with no light perception, downbeat nystagmus, bilateral ocular abduction deficits, cerebellar ataxia as well as a slight psychomotor slowing and mild disorientation. MRI including diffusion-weighted imaging and MR-angiography 3 h after symptom onset did not reveal findings suggestive for ischemic stroke. Immediate iv-application of thiamine led to a nearly complete remission of the neuroophthalmologic symptoms within 12 h. Although we critically discuss other potential etiologies, we conclude that the complex clinical picture with initial sudden blindness is an unusual presentation of WE. © 2007 Elsevier B.V. All rights reserved. Keywords: Wernicke's encephalopathy; Acute blindness; Downbeat nystagmus; Stroke; Alcohol; Diffusion-weighted imaging; Metabolic brain disease
1. Introduction
2. Case report
WE is caused by a thiamine deficit leading to disturbances in cerebral glucose metabolism. Typical early symptoms include oculomotor deficits (frequently bilateral abduction deficits due to VI nerve palsies, and vertical/horizontal nystagmus), ataxia and behavioural/mental disturbances [1]. To date, associated loss of vision has been reported in 8 cases only and mainly developed progressively over a couple of days or could be explained by papilledema or retinal hemorrhage [cf. Table 1, [2–8]]. In the present case bilateral blindness occurred suddenly without acute retinal affection and as an initial symptom. This sudden onset raises the question of other underlying etiologies, especially of brain ischemia, revealing the absence of highly sensitive diagnostic tools in WE and the presence of the diagnostic gap between transient ischemic attack and abnormalities in diffusion-weighted imaging (DWI) in MRI.
A 37-year old male with chronic alcohol abuse was admitted to a nearby psychiatric clinic due to alcohol intoxication (blood alcohol level 3.4‰). 24 h later he suffered from acute, stroke-like bilateral blindness with no light perception (“as if somebody has switched off the light”) and was referred to our centre within 2 h. His medical history comprised a perinatal neuroophthalmologic affection of unknown etiology with a residual scotoma within the temporal visual field on the right eye as well as a discrete esotropia (with deviation of the right bulbus). These neuroophthalmologic problems were stable over more than 30 years. There has been a history of heavy alcohol abuse and chronic tobacco abuse since several years. On admission, the malnourished patient (172 cm, 58 kg, body mass index 19.6 kg/m 2 ) was awake, oriented to time and person, co-operative without apparent mnestic deficits, but with a slight psychomotor slowing and disorientation to his own situation. He denied headache and had no history of migraine. The neuroophthalmologic picture was complex: he presented prominent esotropia
⁎ Corresponding author. Tel.: +49 761 2705296; fax: +49 761 2705310. E-mail address: [email protected] (R. Surges). 0022-510X/$ - see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.jns.2007.04.005
262
R. Surges et al. / Journal of the Neurological Sciences 260 (2007) 261–264
Table 1 Review of visual loss during Wernicke's encephalopathy Ref. Age/ sex
Clinical course of visual loss
Neuroophthalmology
Acuity/funduscopy/ VEP (visually Presumed site of visual field evoked potentials) action (initial examination)
[2]
2 patients. Blindness on day 28/35 a, onset unclear, both patients died. Incomplete loss of vision. Onset and evolution not specified.
Nystagmus
–/Papilledema on day 21 + 28 a/–
[3]
20/F
[4]
40/ M
Progressive visual loss over a couple of days. Incomplete recovery within 3 months upon thiamine.
Horizontal/vertical gaze palsies; LR+
Perception of light only/ normal/–
Uncooperative patient
Cortical
[5]
64/F
Progressive visual loss over a couple of days. Substantial improvement within 1 month upon thiamine. Blindness, onset unclear. Recovery within 1 month upon thiamine. Progressive visual loss over 10 days to blindness. Substantial improvement within 24 h upon thiamine. Sudden onset blindness (no light perception). Recovery within a couple of days upon thiamine. Sudden onset blindness (no light perception). Recovery within 12 h upon thiamine.
Nystagmus upon horizontal gaze
–/normal/–
Flash VEP not reproducible
Unclear
[6] b 39/ M [7]
21/F
[8]
47/F
⁎
37/ M
Horizontal/vertical Reduced/ nystagmus; Horizontal/ papilledema + vertical gaze palsies peripapillary hemorrhage/–
Cranial imaging/MRI
MRI: symmetrical hyperintensities within the thalamus and midbrain (DWI, T2, FLAIR sequences) MRI: discrete white matter lesions and prominent bilateral hyperintensities in nucleus lentiformis (T2). SPECT: unilateral occipital hypoperfusion and bilaterally in thalamus and cerebellum. MRI: symmetrical hyperintensities within the thalamus, midbrain (T2, FLAIR)
Nystagmus
Horizontal/vertical nystagmus; Incomplete gaze palsies in all directions Vertical nystagmus on upgaze; Incomplete vertical/horizontal gaze palsies; Esotropia, LR-, Downbeat nystagmus; Esotropia (bilateral abduction deficits); Mydriasis, LR+
–/bilateral papilledema + retinal hemorrhages/–
–/atrophy of the right optic disc/–
MRI: normal
Pattern VEP pathologic
Optic nerves
Contrast enhanced CT: normal
Not adequately feasible
Cortical
MRI: normal
⁎: our patient. a Days after first and continued parenteral nutrition incidentally without thiamine. b Only abstract in English. LR: pupillary light reaction.
due to severe bilateral abduction defects, a spontaneous downbeat nystagmus and a mydriasis with positive, relatively slow pupillary light reaction. There was no light perception, the menace reflex (brusk hand movements in front of the patient) as well as the “mirror test” (mirror in front of the patient to test whether there is an ocular pursuit movement) were both negative, arguing against visual loss of non-organic origin. The patient additionally presented cerebellar ataxia with bilateral intention tremor on both arms and legs, whereas there was no tremor at rest. Clinical signs of polyneuropathy were completely absent, since all tendon reflexes (ankle jerks included) were brisk without Babinskis sign and sensation (vibration sensation in both arms and legs included) was entirely preserved. Blood
analysis yielded an elevated Gamma-GT (145 U/l; normal b 66 U/l) only. Other liver enzymes, cholinesterase and alcohol level were normal. Thiamine was not examined. ECG was normal. Blood pressure was in a range between 120–150/70–90 mm Hg during his stay in our hospital. Stroke-MRI within 3 h after symptom onset revealed no particularities (see Fig. 1). Since the symptoms were timely related to excessive alcohol consumption, 100 mg intravenous thiamine was rapidly applied and continued during the next days. Within 12 h, downbeat nystagmus as well as vision had completely recovered, the bilateral abduction deficits were markedly improved (a slight esotropia with deviation of the right eye known since childhood persisted). Ophthalmological examination the next day
R. Surges et al. / Journal of the Neurological Sciences 260 (2007) 261–264
263
Fig. 1. Cranial MRI. A: Axial DWI image without apparent diffusion deficits. B: “Time of Flight” angiography with normal flow signal in all cerebral arteries, especially the basilar artery (asterisk) and posterior cerebral artery (pca). C: Coronal FLAIR sequence that only showed artefacts due to movement. D: Axial T2 image without particularities.
revealed the known visual field defect on the right eye due to an atrophy of the optic disc but most importantly without papilledema or retinal hemorrhage. Due to developing delirium tremens with visual hallucinations after 24 h, visually evoked potentials and Goldman perimetry were not adequately feasible and the patient was re-referred to the psychiatric clinic. The intention tremor and ataxia persisted in a milder form for a further few days. On discharge some weeks later, the patient was completely independent and the neurological examination only yielded the known scotoma and the discrete esotropia. Unfortunately, further examinations (e.g. visually evoked potentials and additional ophthalmologic examination) were not done. 3. Discussion WE is clinically diagnosed, since there are no highly sensitive tools to prove this pathological entity. A low serum level of thiamine and a low erythrocyte transketolase
activity can support the diagnosis but lack sensitivity and may not be available immediately. Suggestive MRI findings (bilateral lesions around the third/fourth ventricle, in the medial parts of the thalamus, corpora mamillaria, mesencephalon, tegmentum and periaqueductal) can strengthen the diagnosis, but sensitivity only amounts to about 50% [9]. Newer works report on DWI abnormalities within the typical localization of WE-associated lesions that might precede lesions detected by other MRI sequences [3,10– 16]. In our patient DWI was performed 3 h after sudden symptom onset and was without particularities, whereas the earliest time scale reporting DWI abnormalities was 29 h so far [12]. The most interesting feature is the sudden bilateral blindness during the initial phase of the disease. Although there are various toxicologic and metabolic etiologies known to cause acute loss of vision [17], the most important differential diagnosis to be ruled out is a transient ischemic attack (TIA) in the vertebrobasilar territory. TIA cannot be excluded completely, due to a diagnostic and methodological gap between DWI abnormalities and the occurrence of
264
R. Surges et al. / Journal of the Neurological Sciences 260 (2007) 261–264
TIA: DWI abnormalities in TIA are reported in 35–44% only with an increasing probability of DWI abnormalities beyond 60 min [18,19]. In view of the normal Stroke-MRI 3 h after acute onset and still in the presence of the full clinical picture, the bilateral pattern of neurological symptoms (especially bilateral abduction deficits and the cerebellar ataxia, which does not fit a top of the basilar syndrome, but rather WE), and the fast clinical recovery following thiamine substitution within a clinical context of chronic alcohol abuse, we suggest an unusual presentation of WE. Thiamine pyrophosphate is an essential coenzyme for cerebral glucose metabolism and involved in the regulation of the osmotic gradient across the cell membranes. Functional loss of cortical cells during lack of thiamine is attributed to disturbances in metabolism of glucose, local accumulation of lactate, pyruvate and alanin leading to local acidosis [20] and extra-/intracellular edema that may lead to demyelinisation, glial proliferation, hemorrhagic lesions and necrosis at the WE-typical lesion sites [21]. Concerning the acute vision loss in our patient, the fast clinical recovery suggests a reversible metabolic dysfunction which is not necessarily detected by the recent DWI techniques, as outlined above. Because of the preserved pupillary light reaction and the absence of acute retinal damages we rather propose a cortical site of action, what has already been reported before [4]. In contrast, e.g. a nutritional (“tobacco–alcohol”) amblyopia is rather unprobable because of the preserved pupillary light reaction as well as the fast clinical onset and recovery. An episode of a relapsing chronic inflammatory demyelinating disease could be suggested by the residual atrophy of the optic disc, but the perinatal onset, the absence of clinical progression over more than 30 years and the recent MRI imaging argue against this hypothesis. 4. Conclusion In summary, we report an unusual presentation of WE with initial and sudden onset of bilateral blindness, oculomotor deficits, cerebellar ataxia and a slight psychomotor slowing in a young male alcoholic. Because of the diagnostic dilemma mentioned above, we suggest immediate application of thiamine as well as diagnostic work-up to detect ischemic strokes in rapidly evolving clinical pictures within the context of chronic alcohol abuse. Acknowledgement We thank PD Dr. Ansgar Berlis from the Section of Neuroradiology at the Department of Neurosurgery for providing us the MRI images.
References [1] Victor M, Adams RD, Collins OH. The Wernicke–Korsakoff syndrome and related disorders due to alcoholism and malnutrition. 2nd edition. Philadelphia: Davis; 1989. p. 1–117. [2] Bleggi-Torres LF, de Medeiros BC, Ogasawara VS, Loddo G, Zanis Neto J, Pasquini R, et al. Iatrogenic Wernicke's encephalopathy in allogeneic bone marrow transplantation: a study of eight cases. Bone Marrow Transplant 1997;20:391–5. [3] Halavaara J, Brander A, Lyytinen J, Setala K, Kallela M. Wernicke's encephalopathy: is diffusion-weighted MRI useful? Neuroradiology 2003;45:519–23. [4] Kraus J, Heckmann G, Sommer JB, Erbguth F, Platsch G, Neundörfer B. SPECT-Befunde bei Wernicke Encephalopathie. Aktuelle Neurol 2001;28:128–31. [5] Kuhn J, Friedel V, Knitelius O, Bewermeyer H. Iatrogenes Wernicke– Korsakoff-Syndrom mit ungewöhnlichen Symptomen und MRTVeränderungen. Nervenarzt 2004;75:795–800. [6] Miyashita H, Saitho T, Nakano N, Ishigaki H, Ikemoto M, Uthumi K, et al. A case of Wernicke's encephalopathy which accompanied a passing blindness. Arukoru Kenkyuto Yakubutsu Ison 1994;29:114–20. [7] Tesfaye S, Achari V, Yang YC, Harding S, Bowden A, Vora JP. Pregnant, vomiting and going blind. Lancet 1998;352:1594. [8] Timmings PL, Carroll GJ, Donaldson IM. Wernicke's encephalopathy presenting with blindness. N Z Med J 1993;106:159–60. [9] Antunez E, Estruch R, Cardenal C, Nicolas JM, Fernandez-Sola J, Urbano-Marquez A. Usefulness of CT and MR imaging in the diagnosis of acute Wernicke's encephalopathy. Am J Roentgenol 1998;171:1131–7. [10] Bergui M, Bradac GB, Zhong JJ, Barbero PA, Durelli L. Diffusionweighted MR in reversible Wernicke encephalopathy. Neuroradiology 2001;43:969–72. [11] Chu K, Kang DW, Kim HJ, Lee YS, Park SH. Diffusion-weighted imaging abnormalities in Wernicke encephalopathy: reversible cytotoxic edema? Arch Neurol 2002;59:123–7. [12] Doherty MJ, Watson NF, Uchino K, Hallam DK, Cramer SC. Diffusion abnormalities in patients with Wernicke encephalopathy. Neurology 2002;58:655–7. [13] Ducreux D, Petit-Lacour MC, Benoudiba F, Castelain V, MarsotDupuch K. Diffusion-weighted imaging in a case of Wernicke encephalopathy. J Neuroradiol 2002;29:39–42. [14] Hashimoto T, Ueda H, Mitui Y, Kihara M, Takahashi M, Kusunoki S. Diffusion-weighted magnetic resonance imaging findings at early stage of acute Wernicke encephalopathy. Rinsho Shinkeigaku 2004;44:422–6. [15] Hong KS, Kang DW, Cho YJ, Hwang YJ, Hur G. Diffusion-weighted magnetic resonance imaging in Wernicke's encephalopathy. Acta Neurol Scand 2002;105:132–4. [16] Unlu E, Cakir B, Asil T. MRI findings of Wernicke encephalopathy revisited due to hunger strike. Eur J Radiol 2006;57:43–53. [17] Purvin V, Kawasaki A. Neuro-ophthalmic emergencies for the neurologist. Neurologist 2005;11:195–233. [18] Inatomi Y, Kimura K, Yonehara T, Fujioka S, Uchino M. DWI abnormalities and clinical characteristics in TIA patients. Neurology 2004;62:376–80. [19] Lamy C, Oppenheim C, Calvet D, Domigo V, Naggara O, Meder JL, et al. Diffusion-weighted MR imaging in transient ischaemic attacks. Eur Radiol 2006;16:1090–5. [20] Hakim AM. The induction and reversibility of cerebral acidosis in thiamine deficiency. Ann Neurol 1984;16:673–9. [21] Harper CG. The incidence of Wernicke's encephalopathy in Australia: a neuropathological study of 131 cases. J Neurol Neurosurg Psychiatry 1983;46:519–23.