[Recurrent chronic Vogt-Koyanagi-Harada syndrome or sarcoidosis? A Gloomy diagnosis]. / ¿Síndrome de Vogt-Koyanagi-Harada crónico o sarcoidosis? Un diagnóstico sombrío.

Background: Vogt-Koyanagi-Harada syndrome (VKH) is a systemic disease that affects organs profuse in melanocytes, presenting with a chronic and diffuse bilateral granulomatous panuveitis, as well as neurological, auditory, and cutaneous manifestations. In this article, a systematic approach is presented for the diagnostic management of VKH syndrome, considering relevant diagnostic possibilities to rule out other entities that manifest similar symptoms. Clinical case: 71-year-old man with a long-standing history of vitiligo, who experienced visual loss in his right eye 6 months before his admission, along with bilateral hearing loss predominantly in the right ear. During his hospitalization, he presented with chronic headache, fever, and significant involuntary weight loss. Ophthalmological examination revealed that his right eye only perceived light and had hyperemic bulbar conjunctiva, while the left eye had a visual acuity of 20/200. The right fundus had scattered pigmentation, while the left had an edematous optic disc and right optic atrophy. Conclusions: The diagnosis of VKH syndrome is established by the presence of the 5 diagnostic criteria for complete disease, including retinal depigmentation, neurological alterations, and dermatological manifestations. Since patients can present with a wide variety of symptoms, initial differential diagnosis should be considered, which represents a diagnostic challenge.

Introducción: el síndrome de Vogt-Koyanagi-Harada (VKH) es una enfermedad sistémica que afecta a órganos ricos en melanocitos y se manifiesta con una panuveítis granulomatosa bilateral, crónica y difusa, así como con manifestaciones neurológicas, auditivas y cutáneas. En este artículo se presenta un enfoque sistemático para el abordaje diagnóstico del síndrome de VKH y se consideran las posibilidades diagnósticas relevantes para descartar otras entidades que se presentan con síntomas similares. Caso clínico: hombre de 71 años con antecedentes de vitiligo de larga data, quien experimentó una pérdida visual en su ojo derecho seis meses antes de su ingreso, junto con hipoacusia bilateral, predominantemente en el oído derecho. Durante su hospitalización, presentó cefalea crónica, fiebre y una significativa pérdida involuntaria de peso. En la exploración oftalmológica, el ojo derecho solo percibía luz y presentaba conjuntiva bulbar hiperémica, mientras que el ojo izquierdo tenía una agudeza visual de 20/200. El fondo del ojo derecho presentaba pigmentación dispersa, mientras que el izquierdo tenía una papila edematosa y atrofia óptica derecha. Conclusiones: el diagnóstico del síndrome de VKH se establece mediante la presencia de los 5 criterios diagnósticos para la enfermedad completa, incluida la hipopigmentación retiniana, las alteraciones neurológicas y las manifestaciones dermatológicas. Dado que los pacientes pueden presentar una amplia variedad de síntomas, el diagnóstico diferencial debe considerarse inicialmente, lo que representa un desafío diagnóstico.

Immunization with neural-derived antigens inhibits lipid peroxidation after spinal cord injury.

Lipid peroxidation (LP) is one of the most harmful mechanisms developed after spinal cord (SC) injury. Several strategies have been explored in order to control this phenomenon. Protective autoimmunity is a physiological process based on the modulation of inflammatory cells that can be boosted by immunizing with neural-derived peptides, such as A91. Since inflammatory cells are among the main contributors to lipid peroxidation, we hypothesized that protective autoimmunity could reduce LP after SC injury. In order to test this hypothesis, we designed two experiments in SC contused rats. First, animals were immunized with a neural-derived peptide seven days before injury. With the aim of inducing the functional elimination of CNS-specific T cells, for the second experiment, animals were tolerized against SC-protein extract and thereafter subjected to a SC injury. The lipid-soluble fluorescent products were used as an index of lipid peroxidation and were assessed after injury. Immunization with neural-derived peptides reduced lipid peroxidation after SC injury. Functional elimination of CNS-specific T cells avoided the beneficial effect induced by protective autoimmunity. The present study demonstrates the beneficial effect of immunizing with neural-derived peptides on lipid peroxidation inhibition; besides this, it also provides evidence on the neuroprotective mechanisms exerted by protective autoimmunity.

Cyclosporin-A enhances non-functional axonal growing after complete spinal cord transection.

Therapeutic approaches that promote both neuroprotection and neuroregeneration would be valuable for spinal cord (SC) injury therapies. Cyclosporin-A (CsA) is an immunosuppressant that, due to its mechanism of action, could both protect and regenerate the neural tissue after injury. Previous studies have already demonstrated that intraperitoneal administration of CsA at a dose of 2.5 mg/kg/12 h during the first 2 days after SC contusion, followed by 5 mg/kg/12 h orally, diminishes tissue damage and improves motor recovery. In order to evaluate the effect of this CsA dosing regimen on axonal growth, we assessed motor recovery, presence of axons establishing functional connections and expression of GAP-43 in rats subjected to a complete SC transection. The Basso-Beattie-Bresnahan rating scale did not show difference in motor recovery of CsA or vehicle-treated rats. Moreover, somato-sensorial evoked potentials demonstrated no functional connections in the SC of these animals. Nevertheless, histological studies showed that: i) a significant number of CsA-treated rats presented growing axons, although they deviated perpendicularly at the edge of the stumps, surrounding them, ii) the expression of GAP-43 in animals treated with CsA was higher than that observed in the control group. Finally, anterograde tracing of the corticospinal tract of rats subjected to an incomplete SC transection showed no axonal fibers reaching the caudal stump. In summary, CsA administered at the dosing-regimen that promotes neuroprotection in SC contused rats induces both GAP-43 expression and axonal growth; however, it failed to generate functional connections in SC transected animals.