Factors contributing to delay in diagnosis of Guillain-Barré syndrome and impact on clinical outcome.

INTRODUCTION: Heterogeneity of presenting symptoms makes the initial clinical diagnosis of Guillain-Barré syndrome (GBS) challenging. METHODS: Observational retrospective study from 2 teaching hospitals (Parkland Memorial Hospital and University of Texas Southwestern University Hospital) between 2008 and 2013. RESULTS: Sixty-nine GBS patients were identified. GBS was suspected on initial emergency department visit in only 49%. During first hospital encounter, 58% were evaluated by a neurologist. Neuropathic pain and presence of intact deep tendon reflexes were associated with delayed GBS diagnosis (P < 0.05). There was significantly better clinical outcome among patients who were evaluated by a neurologist during the initial visit (P < 0.005). Among these patients there was also significant difference in discharge destination; 71.2% of patients evaluated by a neurologist were discharged home (P < 0.01). Patients in whom GBS was not suspected at the time of initial Neurology evaluation were more likely to require intubation and to have residual weakness at the time of discharge (P < 0.05). CONCLUSIONS: Atypical clinical signs and symptoms may lead to delayed diagnosis of GBS. Early neurological evaluation is associated with improved clinical diagnosis and discharge disposition.

The spectrum of autoimmune encephalopathies.

Despite being a potentially reversible neurological condition, no clear guidelines for diagnosis or management of autoimmune encephalitis exist. In this study we analyzed clinical presentation, laboratory and imaging characteristics, and outcome of autoimmune encephalitis from three teaching hospitals. Non-paraneoplastic autoimmune encephalitis associated with antibodies against membrane antigens was the most common syndrome, especially in the pediatric population. Clinical outcome was better for patients with shorter latency from symptom onset to diagnosis and initiation of immunomodulation. Patients with underlying malignancy were less likely to respond well to immunomodulatory therapy. The clinical spectrum of autoimmune encephalitis is fairly broad, but prompt recognition and treatment often leads to excellent outcome.

Herpes simplex encephalitis as a potential cause of anti-N-methyl-D-aspartate receptor antibody encephalitis: report of 2 cases.

IMPORTANCE: Encephalitis mediated by anti-N-methyl-D-aspartate (NMDA) receptor antibodies and herpes simplex (HS) encephalitis are seemingly separate causes of encephalopathy in adults and children. Herpes simplex encephalitis is infectious, and anti-NMDA receptor antibody encephalitis is autoimmune in origin. Both can cause seizures and encephalopathy, although the latter can also cause psychiatric symptoms and movement disorders. Owing to the rarity of these 2 diseases, patients with co-occurrence are important because they alert clinicians to possible links between 2 seemingly separate processes. OBSERVATIONS: In a case series of 2 patients observed at our center, we describe an infant and an adult who had confirmed HS encephalitis and then developed confirmed anti-NMDA receptor antibody encephalitis. Polymerase chain reaction testing for HS virus was performed. Testing for NMDA receptor antibodies was performed by Associated Regional and University Pathologists Laboratory in Salt Lake City, Utah. CONCLUSIONS AND RELEVANCE: We conclude that atypical cases of HS or other viral encephalitides should be investigated for concomitance of an autoimmune encephalitis. We suspect that the pathophysiologic mechanisms by which HS virus infects neurons produce a higher likelihood of contracting anti-NMDA receptor antibody encephalitis.

Clinical Reasoning: a woman with recurrent aphasia and visual field defects.

A 73-year-old woman with a history of hypertension and a recent stroke presented with recurrent nonsensical speech and visual problems. One month prior, she had been diagnosed with a stroke, after sudden-onset speech and visual difficulties that resolved after a few hours. Thirteen days before, she had had a second episode of similar symptoms. She was seen in our institution after a few hours of sudden-onset unintelligible speech. Her vital signs were within normal limits. She was not in distress, but appeared frustrated. Her general physical examination was unremarkable. She had no carotid, ophthalmic, or cranial bruits. Her neurologic examination was notable for fluent aphasia, with paraphasic errors and inability to name, read, or write. She also had right homonymous hemianopia, right-sided sensory loss, and generalized brisk deep tendon reflexes. The rest of her neurologic examination showed no abnormalities.

Multifocal paraneoplastic cortical encephalitis associated with myasthenia gravis and thymoma.

OBJECTIVES: To report a case of multifocal cortical encephalitis associated with thymoma and to establish an association of this thymoma-related paraneoplastic syndrome with voltage-gated potassium channel antibodies. DESIGN: Case report. SETTING: University hospital. PATIENT: A 43-year-old woman with a history of seropositive myasthenia gravis and successfully treated invasive thymoma. Four years after thymectomy, she presented with seizure and rapidly progressive confusion and aphasia. Myasthenia gravis remained in pharmacological remission. Magnetic resonance imaging of the brain showed innumerable cortically based signal abnormalities as well as extensive left mesial temporal lobe abnormality with minimal enhancement. RESULTS: Chest computed tomography showed abnormal pleural thickening of the left lung, which proved to be recurrent metastatic thymoma. Results of serological evaluation were positive for acetylcholine receptor, striational, and voltage-gated potassium channel antibodies. She showed partial improvement in response to immunotherapy and chemotherapy but ultimately died 2 months later of tumor complications. CONCLUSIONS: Thymoma and myasthenia gravis may be associated with other autoimmune neurological disorders including paraneoplastic encephalitis. This second case of thymoma-associated multifocal cortical encephalitis demonstrates that autoimmune encephalitis can extend to cortical regions outside the limbic system. Autoimmune encephalitis should be considered in the differential diagnosis of patients with myasthenia gravis or thymoma who develop new cognitive symptoms.

Optic neuritis presenting with amaurosis fugax.

Optic neuritis usually presents with rapid and gradual loss of vision that is either complete or incomplete, and typically associated with retro-orbital pain. To our knowledge there have been no documented reports of optic neuritis presenting with multiple episodes of amaurosis fugax, the sudden and transient loss of vision lasting seconds to minutes. We report here the case of a young woman with a possible diagnosis of demyelinating left optic neuritis that presented solely with multiple episodes of brief and transient sudden loss of vision. Ophthalmological exams were normal between episodes of vision loss. The patient's magnetic resonance imaging of the brain showed a subtle enhancement of the left optic nerve along with multiple periventricular lesions, highly suggestive of a demyelinating disease. The frequent episodes of visual loss resolved completely with high dose parenteral steroids. Neurologists and other clinicians should be aware of this unusual presentation of optic neuritis as treatment modalities differ greatly from other causes of amaurosis fugax.