2821 Bilateral dysgeusia secondary to post-coital unilateral thalamic ischaemic stroke

Introduction This case report describes a twenty-five-year-old female with bilateral loss of taste secondary to right anterior ischaemic thalamic stroke.

Methods A single case report of a patient admitted to Mater Hospital, Australia with review of related published case reports.

Results A right-handed twenty-five-year-old female presented with post-coital acute onset headache, dizziness, dysarthria & left-sided facial droop. Initial symptoms resolved & the patient became aware of bilateral loss of taste. She described limited ability identifying foods previously enjoyed & subsequent dissatisfaction with oral intake.

Dysgeusia was evident on examination bilaterally with all tested food stimuli.

MRI revealed a focus of restricted diffusion in the right hemi-thalamus consistent with acute ischaemic stroke. CT head and neck angiogram were unremarkable with no evidence of vasospasm. Trans-oesophageal echocardiogram reported a positive agitated saline contrast study suggestive of patent foramen ovale & referred for closure.

Discussion The dorsomedial thalamic nucleus is involved in both intensity of taste perception and the hedonic nature of oral intake.¹ Both thalami provide bilateral taste perception, however there is marked variability in innervation, with rare reports of unilateral thalamic strokes resulting in bilateral loss of taste.²

The reward pathways associated with pleasant taste sensations are important for motivating oral intake and maintaining nutrition. Gustatory dysfunction generally improves, but is important to address in the acute stroke period including nutritional assessment, diet modifications & associated mood disorder.¹

Conclusions Bilateral dysgeusia secondary to unilateral thalamic stroke is a very rare stroke complication with associated serious patient consequences including malnutrition.

References

1. Uider FM, Sivagnanaratnam A. Bilateral loss of taste from a unilateral thalamic infarct. Practical Neurology. 2021;0:1–4.

2. Kogawa S, Yamakawa I, Nakajima A, et al. Bilateral ageusia caused by right thalamic infarction. Rinsho Shinkeigaku. 2013;53:24–8.