Miller Fisher Syndrome presenting as unilateral abducens nerve palsy: A case report

Background : Miller Fisher Syndrome usually presents with complete ophthalmoplegia, areflexia and ataxia. We present an unusual case which presented with unilateral abducens nerve palsy. Case presentation : A 51 year old female patient presented with a history of difficulty in walking and double vision for 1 week which started 2 weeks following an episode of acute gastroenteritis. She didn’t have any bladder bowel incontinence or difficulty in breathing. On examination there was left side abducens nerve palsy and bilateral significant dysmetria. Upper limb and lower limb power was 4/5 with global areflexia. There was no fatigability or sensory deficit. Higher cortical functions were intact with Glasgow Coma Scale of 15/15. Brain stem cerebro vascular accident, alcohol, toxin or drug mediated disease, myasthenia gravis, Bickerstaff encephalitis and Miller-Fisher syndrome were considered as possible differential diagnosis. There was no history of alcohol consumption or any exposure to drugs or toxins. Her Non contrast brain and MRI brain were normal. Nerve conduction study showed asymmetrical sensory motor and F wave abnormalities consistent with a Guillen-Barre Sydrome variant. Cerebro Spinal Fluid analysis showed albumino-cytological dissociation. These findings suggested the diagnosis of Miller-Fisher Syndrome. She was started on plasmaphareis. Her vital parameters, vital capacity and neurological deficit were closely monitored. With 5 cycles of plasmapharesis she made a complete neurological recovery and she was discharged on 16th day of admission. Conclusion: Miller Fisher Syndrome can present as unilateral abducens nerve palsy and early diagnosis and treatment leads to excellent functional outcome.


Abstract
Background : Miller Fisher Syndrome usually presents with complete ophthalmoplegia, areflexia and ataxia. We present an unusual case which presented with unilateral abducens nerve palsy. Case presentation : A 51 year old female patient presented with a history of difficulty in walking and double vision for 1 week which started 2 weeks following an episode of acute gastroenteritis. She didn't have any bladder bowel incontinence or difficulty in breathing. On examination there was left side abducens nerve palsy and bilateral significant dysmetria. Upper limb and lower limb power was 4/5 with global areflexia. There was no fatigability or sensory deficit. Higher cortical functions were intact with Glasgow Coma Scale of 15/15. Brain stem cerebro vascular accident, alcohol, toxin or drug mediated disease, myasthenia gravis, Bickerstaff encephalitis and Miller-Fisher syndrome were considered as possible differential diagnosis. There was no history of alcohol consumption or any exposure to drugs or toxins. Her Non contrast brain and MRI brain were normal. Nerve conduction study showed asymmetrical sensory motor and F wave abnormalities consistent with a Guillen-Barre

Case Presentation
A 51 year old lady presented to us with a history of difficulty in walking and double vision for 1 week duration. She had an acute gastroenteritis episode 2 weeks prior to her symptoms. Initially she noted imbalance of her body associated with difficulty in walking. On second day she also developed double 3 vision specially when looking to left side. She initially consulted her family doctor who referred to her to our ward for further investigation and management. There was no history of headache or falls. She didn't complain of worsening of symptoms with activity. Also there was no bladder bowel incontinence or difficulty in breathing. Past medical and surgical history was not significant and she was not on any regular medication. Family history was non contributory. She was a housewife and mother of 2 children. There was no occupational exposure to neuro toxins. We couldn't elicit a history of alcohol or substance abuse.
On examination she was not febrile, not pale and anicteric. There was no neck stiffness and Kernig's sign was negative. She was conscious, rational and oriented in time, place and person. Mini mental state examination was normal. Her Glasgow coma score was 15/15. Pupils were symmetrical and equally reacted to light. There was left sided Abducens nerve palsy but there was no ptosis and rest of the cranial nerve examination was normal. Power of all four limbs was 4 but she had global areflexia. Plantar response was flexor. Fatigability of muscle power was not elicited. There was no objective sensory deficit. Romberg's sign was negative. Unsteady gait was noted with impaired fingernose test and heel-knee-shin test. Her vital parameters, single breath count and vital capacity were normal. Fundoscopy didn't show papilloedema or any other changes. Ethics approval and consent to participate: Informed written consent was obtained from the patient to use her data for this case report. Ethics approval not applicable as this is a case report. Consent for publication : Informed written consent was obtained from the patient to publish data regarding her disease.
Availability of data and materials : The data used for this case report are available from the corresponding author on reasonable request.
Competing interests: The authors declare that they have no competing interests.
Funding: There is no source of funding.
Authors' contributions: SDNDS collected data and wrote the manuscript. SS contributed in literature survey and manuscript writing. CEDS provided advice and edited the manuscript. All authors read and approved the final manuscript.
Acknowledgements: Not applicable