Acute optic neuritis: What do complementary tests add to diagnosis?

INTRODUCTION: Optic neuritis (ON) is the inflammation of the optic nerve due in many cases, to a pathological immune response. Since its symptoms can be subtle, diagnosis is sometimes challenging. The value of complementary tests for diagnosis and prognosis of ON was demonstrated in retrospective analysis, but their utility in the acute period of ON has been scarcely studied. The aim of this study is to determine the usefulness of clinical assessment, optical coherence tomography (OCT), visual evoked potentials (VEP) and orbit magnetic resonance imaging (MRI) for making diagnosis and prognosis of acute ON (AON). MATERIALS AND METHODS: A cross-sectional study was conducted including patients with ON within 90 days of symptom onset. A complete neuro-ophthalmological evaluation, OCT, VEP and MRI were carried out, determining in each case its sensitivity, specificity and predictive values in the diagnosis of ON and the assessment of its severity. RESULTS: 75 eyes of 34 patients with ON were included. Regarding diagnosis, low contrast visual acuity (LCVA) displayed the highest sensitivity (100%), being superior than the sensitivity of all complementary tools, always below 80%. Orbit MRI abnormal findings has a Specificity of 100% to confirm diagnosis. Regarding severity assessment and prognosis, Ganglion cell +inner plexiform layer (GCIP) thickness, but not retinal nerve fibre layer (RNFL), correlates significantly with patients' visual acuity (VA) (p < 0.05). Furthermore, both P100latency and VEP's amplitude showed to be significantly associated with VA (p < 0.05) in the acute period. The combination of two predictors (measurement of RNFL and GCIP) are capable of explaining 60% of the variation of the patient's visual acuity, with statistical significance (p = 0.02) CONCLUSIONS: In depth neuro-ophthalmological assessment during the acute phase of ON, including contrast sensitivity measurement, proved to be superior to complementary tests for diagnosis, surpassing the performance of OCT and VEP. However, these tools can add to prognosis, as GCIP thickness and VEP's amplitude correlate with disease severity and its findings could encourage prompt aggressive treatments in AON.

[Early Clinical Diagnosis of Anti-NMDA Receptor Encephalitis: Case Series and Literature Review]. / Diagnóstico clínico temprano de la Encefalitis Anti-Receptor NMDA: Serie de casos y revisión bibliográfica.

Autoimmune encephalitis refers to a group of pathologies described in the last two decades, characterized by neuropsychiatric symptoms of subacute presentation, mediated by antibodies directed against neuronal membrane proteins. Within this group, encephalitis mediated by antibodies against the NMDA receptor of glutamate is a particular clinical entity, given that its expression is dominated by psychiatric symptoms that usually occur at the onset of the disease. In this paper we describe five cases of NMDA encephalitis in adult patients followed up in the last four years in a public hospital in the City of Buenos Aires, Argentina. We also include a review of the current literature. We emphasize the clinical description of the psychiatric symptoms of presentation, since these lead to the patient's first contact with the health system. Given the difficulty in our environment to implement the determination of autoantibodies, the ability to clinically recognize this pathology becomes paramount to establish an early preliminary diagnosis and not to delay immunosuppressive therapy, thus allowing for a better prognosis.