The multiple autoimmune syndromes. A clue for the autoimmune tautology

The multiple autoimmune syndromes (MAS) consist on the presence of three or more well-defined autoimmune diseases (ADs) in a single patient. The aim of this study was to analyze the clinical and genetic characteristics of a large series of patients with MAS. A cluster analysis and familial aggregation analysis of ADs was performed in 84 patients. A genome-wide microsatellite screen was performed in MAS families, and associated loci were investigated through the pedigree disequilibrium test. Systemic lupus erythematosus (SLE), autoimmune thyroid disease (AITD), and Sjögren's syndrome together were the most frequent ADs encountered. Three main clusters were established. Aggregation for type 1 diabetes, AITD, SLE, and all ADs as a trait was found. Eight loci associated with MAS were observed harboring autoimmunity genes. The MAS represent the best example of polyautoimmunity as well as the effect of a single genotype on diverse phenotypes. Its study provides important clues to elucidate the common mechanisms of ADs (i.e., autoimmune tautology). © Springer Science+Business Media, LLC 2012.

Plasmapheresis vs. immunoglobulin in autoimmune neurologic diseases: a meta-analysis

Objectives: to evaluate the efficacy and safety of human immunoglobulin versus plasmapheresis in the management of autoimmune neurologic diseases. Likewise, length of hospital stay and duration of ventilator support were compared. Methods: Randomized controlled trials and analytical observational studies of more than 10 cases, were reviewed. Cochrane Neuromuscular Disease Group trials, MEDLINE, EMBASE, HINARI Ovid, the Database of abstracts of reviews of effectiveness and the Economic evaluation Database were searched as data source. Reference lists were examined for further relevant articles. A random-effect model was used to derive a pooled risk ratio. Results: 725 articles were found and 27 met the criteria for a population studied of 4717 cases: 14 articles were about Guillain Barré syndrome, 10 of Myasthenia Gravis, one of Sydenham Chorea, one of Chronic inflammatory demyelinating polyneuropathy, and one of PANDAS. No evidence was found in favor of any of the two treatments as regards effectiveness (OR 0.94, IC 0.63 – 1.41, p= 0.77) or ventilator support time; IGIV had a significant better safety profile than plasmapheresis (OR 0.70, IC 0.51 – 0.96, p= 0.03) and patients needed less time of hospital stay (p=0.03). Conclusions: There is no evidence for superiority in the effectiveness of immunoglobulin or plasmapheresis in the management of autoimmune neurologic diseases. Nevertheless, patients treated with immunoglobulin have statistically significant less adverse effects, a shorter hospital stay and a tendency of less ventilator support time. These premises could lead to fewer costs for health services but an economic study should be done.

Infección por virus sincitial respiratorio y su relación con valores de IGG en niños críticos

Antecedente: La infección por el virus sincitial respiratorio (VSR) representa una elevada morbimortalidad, y en algunos casos necesidad de manejo en unidades de cuidado intensivo pediátrico (UCIP). La respuesta inmunológica influye de manera directa en la expresión de la severidad y pronóstico de los pacientes con infección respiratoria. Metodología: Estudio de una cohorte retrospectiva de pacientes con infección respiratoria grave secundaria a VSR, sin historia de inmunodeficiencia, atendidos en la UCIP del Hospital Universitario Clínica San Rafael. Se realizó análisis descriptivoglobaly de acuerdo a la categorización de las prueba de IgG. Resultados: De 188 pacientes que ingresaron a la UCIP, 13% presentaron infección por VSR (24), con una edad promedio de 7,3 (DE=3,6) meses. Pertenecían al sexo masculino79,83%. Se encontró que 12,5% tenían un valor de IgGbajo para su edad, 58,33% tenían valores en límite inferior y el 29,17% dentro de rangos normales para su edad. En los pacientes con IgG baja, fue mayor la presentación de choque séptico que no responde a líquidos (100 vs 92 vs 86%), la mediana de días de ventilación mecánica fue mayor (8 vs 6 vs 5 respectivamente), así como la mortalidad (67 vs 7,1 vs 0%). Conclusión: Nuestra serie encontró que aquellos pacientes con niveles bajos o valores en el límite inferior de IgG sérica tuvieron mayor compromiso sistémico, mayor duración de ventilación mecánica y mayor mortalidad. Se necesitan estudios prospectivos que relaciones niveles bajos de IgG con severidad y pronostico en estos pacientes con infección grave por VSR.