Fenómeno de Raynaud por exposición a cloruro de vinilo / Raynaud's phenomenon secondary to vinyl chloride exposure

El policloruro de vinilo (PVC) es el polímero que ocupa el tercer puesto en el mercado de producción de plásticos a nivel mundial. Como consecuencia de la exposición crónica, los operarios pueden desarrollar cambios óseos degenerativos, Raynaud, trastornos circulatorios en extremidades, trombocitopenia y lesiones cutáneas semejantes a esclerodermia; esto se conoce como “enfermedad por cloruro de vinilo”. Presentamos un paciente masculino de 24 años de edad que presenta fenómeno de Raynaud, cefaleas, malestar en manos y pies, sensación de frío, fatiga y pérdida de apetito asociado a exposición a policloruro de vinilo. El estudio de la microcirculación cutánea periungueal por videocapilaroscopía muestra alteraciones estructurales y funcionales características. Se recomienda un seguimiento multidisciplinario estricto de los trabajadores expuestos a PVC.

Childhood systemic lupus erythematosus in Latin America. The GLADEL experience in 230 children.

To evaluate disease characteristics of childhood onset SLE in Latin America and to compare this information with an adult population in the same cohort of GLADEL. A protocol was designed as a multicenter, multinational, inception cohort of lupus patients to evaluate demographic, clinical, laboratory and serological variables, as well as classification criteria, disease activity, organ damage and mortality. Descriptive statistics, chi square, Fisher's exact test, Student's t test and multiple logistic regression were used to compare childhood and adult onset SLE. 230 patients were <18 years and 884 were adult SLE patients. Malar rash, fever, oral ulcers, thrombocytopenia and hemolytic anemia and some neurologic manifestations were more prevalent in children (p<0.05). On the other hand, myalgias, Sjögren's syndrome and cranial nerve involvement were more frequently seen in adults (p<0.05). Afro-Latin-American children had a higher prevalence of fever, thrombocytopenia and hemolytic anemia. White and mestizo children had a higher prevalence of malar rash. Mestizo children had a higher prevalence of cerebrovascular disease and cranial nerve involvement. Children met SLE ACR criteria earlier with higher mean values than adults (p: 0.001). They also had higher disease activity scores (p: 0.01), whereas adults had greater disease damage (p: 0.02). In Latin America, childhood onset SLE seems to be a more severe disease than adults. Some differences can be detected among ethnic groups.

Argentine population genetic structure: large variance in Amerindian contribution.

Argentine population genetic structure was examined using a set of 78 ancestry informative markers (AIMs) to assess the contributions of European, Amerindian, and African ancestry in 94 individuals members of this population. Using the Bayesian clustering algorithm STRUCTURE, the mean European contribution was 78%, the Amerindian contribution was 19.4%, and the African contribution was 2.5%. Similar results were found using weighted least mean square method: European, 80.2%; Amerindian, 18.1%; and African, 1.7%. Consistent with previous studies the current results showed very few individuals (four of 94) with greater than 10% African admixture. Notably, when individual admixture was examined, the Amerindian and European admixture showed a very large variance and individual Amerindian contribution ranged from 1.5 to 84.5% in the 94 individual Argentine subjects. These results indicate that admixture must be considered when clinical epidemiology or case control genetic analyses are studied in this population. Moreover, the current study provides a set of informative SNPs that can be used to ascertain or control for this potentially hidden stratification. In addition, the large variance in admixture proportions in individual Argentine subjects shown by this study suggests that this population is appropriate for future admixture mapping studies.

Chromosome 17p12-q11 harbors susceptibility loci for systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the presence of autoantibodies against intracellular components, the formation of immune complexes, and inflammation in various organs, typically the skin and kidney glomeruli. The etiology of the disease is not well understood but is most likely the result of the interaction between genetic and environmental factors. In order to identify susceptibility loci for SLE, we have performed genome scans with microsatellite markers covering the whole genome in families from Argentina, Italy, and Europe. The results reveal a heterogeneous disease with different susceptibility loci in different family sets. We have found significant linkage to chromosome 17p12-q11 in the Argentine set of families. The maximum LOD score was given by marker D17S1294 in combination with D17S1293, when assuming a dominant inheritance model (Z = 3.88). We also analyzed a repeat in the promoter region of the NOS2A gene, a strong candidate gene in the region, but no association was found. The locus on chromosome 17 has previously been identified in genetic studies of multiple sclerosis families. Several other interesting regions were found at 1p35, 1q31, 3q26, 5p15, 11q23 and 19q13, confirming previously identified loci for SLE or other autoimmune diseases.

Raynaud primario y secundario a síndromes esclerodermiformes: comunicación de 97 pacientes estudiados por capilaroscopía periungueal / Primary Raynaud and secondary to sclerodermoform syndromes: a communication of 97 patients studies with periungueal capilaroscopy

La detección temprana de síndromes esclerodermoformes es de gran relevancia para el pronóstico del paciente. Nuestro objetivo es determinar la utilidad de la capilaroscopía periungueal en el diagnóstico diferencial entre Raynaud primario y secundario a síndromes esclerodermiformes. Se estudian pacientes con Raynaud primario (21), Raynaud secundario a síndromes esclerodermia sistémica (57) y Raynaud secundario a síndromes de superposición con esclerodermia (19). El grupo control de sujetos sin Raynaud estudiados fue de 40 personas. Todos los grupos fueron estudiados por capilaroscopía periungueal de dedos de ambas manos por medio de microscopio esteroscópico de 40 aumentos. La especificidad del método para detección de patrón SD (esclerodermiforme) fue de 100 por ciento y la sensibilidad asciende 82,5 por ciento para esclerodermia sistémica y 57 por ciento para síndromes de superposición (AU)

Raynaud primario y secundario a síndromes esclerodermiformes: comunicación de 97 pacientes estudiados por capilaroscopía periungueal / Primary Raynaud and secondary to sclerodermoform syndromes: a communication of 97 patients studies with periungueal capilaroscopy

La detección temprana de síndromes esclerodermoformes es de gran relevancia para el pronóstico del paciente. Nuestro objetivo es determinar la utilidad de la capilaroscopía periungueal en el diagnóstico diferencial entre Raynaud primario y secundario a síndromes esclerodermiformes. Se estudian pacientes con Raynaud primario (21), Raynaud secundario a síndromes esclerodermia sistémica (57) y Raynaud secundario a síndromes de superposición con esclerodermia (19). El grupo control de sujetos sin Raynaud estudiados fue de 40 personas. Todos los grupos fueron estudiados por capilaroscopía periungueal de dedos de ambas manos por medio de microscopio esteroscópico de 40 aumentos. La especificidad del método para detección de patrón SD (esclerodermiforme) fue de 100 por ciento y la sensibilidad asciende 82,5 por ciento para esclerodermia sistémica y 57 por ciento para síndromes de superposición