Caracterización clínico epidemiológica del acné conglobata en las provincias de Holguín y Granma / Clinical Epidemiological Description of Conglobate Acne in Holguin and Granma Provinces

Introducción: el acné es una de las afecciones dermatológicas más frecuentes en la práctica médica, de ellas, el acné conglobata se caracteriza por ser poco común. La génesis del acné conglobata es compleja y depende de la interacción de varios factores, entre ellos, los genéticos. Objetivo: caracterizar de forma clínica, epidemiológica e histopatológica el acné conglobata en familiares de la región Holguín -Granma. Método: se realizó un estudio de serie de casos en el período comprendido de enero 2000 a diciembre 2014. Se describió el contexto medioambiental donde se desarrollaron los enfermos. Los enfermos fueron examinados para confeccionar el árbol genealógico, se le realizó seguimiento clínico de las lesiones y biopsia para estudio histopatológico. Resultados: la enfermedad afectó a mujeres y hombres en edad antes de 21 años. Las primeras lesiones generalmente fueron noduloquísticas. Los quistes, los nódulos, los macrocomedones, los conglomerados fistulizados, las bridas cicatriciales tuvieron poca capacidad de resolución con el tratamiento convencional y alcanzaron grandes tamaños a medida que avanzó el tiempo de evolución. Las lesiones se distribuyeron con predilección en la espalda, las axilas y los glúteos. Los cambios histopatológicos fueron la hiperqueratosis con tapones córneos, las alteraciones foliculares y la presencia de los quistes de inclusión epidérmica con trayectos fistulosos. La herencia se comportó autonómico dominante. Las zonas con mayor número de casos fueron las dispuestas en las márgenes del río Cauto y en lugares aledaños. Conclusiones: se definieron los elementos diagnósticos de la enfermedad, tanto clínico y epidemiológicos, como histopatológicos.

Introduction: acne is one of the most frequent dermatology affections in medical practices, and conglobate acne is characterized as uncommon. The genesis of this illness is complicated and depends on the interaction of many factors, for example the genetic factors. Objective: to describe histopatological, epidemiological and clinically the conglobate acne incidence in some families from Holguín - Granma regions. Method: a case series study was carried out for the period from January 2000 to December 2014. The environmental context where the patients were developed was described. The patients were examined to make the family tree, clinical follow-up of lesions and biopsy for histopathological study. Results: the disease affected women and men before the age of 21. The nodule cystic lesions were the first ones. Nodules, macrocomedones, fistulized conglomerates, scar flanges had little resolution capacity with conventional treatment and reached large sizes as the evolution time advanced. The lesions were distributed with a preference in the back, underarms and glutes. Histopathological changes were hyperkeratosis with corneal plugs, follicular alterations and the presence of epidermal inclusion cysts with fistulous pathways. The inheritance behaved autonomously dominant. The areas with the highest number of cases were those located on the banks of the Cauto River and in surrounding areas. Conclusions: the diagnostic elements of the disease, both clinical and epidemiological, as well as histopathological, were defined.

Unexpanded and intermediate CAG polymorphisms at the SCA2 locus (ATXN2) in the Cuban population: evidence about the origin of expanded SCA2 alleles.

The role of short, large or intermediate normal alleles (ANs) of the ataxin-2 gene in generating expanded alleles (EAs) causing spinocerebellar ataxia type 2 (SCA2) is poorly understood. It has been postulated that SCA2 prevalence is related to the frequency of large ANs. SCA2 shows the highest worldwide prevalence in Cuban population, which is therefore a unique source for studying the relationship between the frequency of large and intermediate alleles and the frequency of SCA2 mutation. Through genetic polymorphism analyses in a comprehensive sample (~3000 chromosomes), we show that the frequency of large ANs in the ataxin-2 gene is the highest worldwide, although short ANs are also frequent. This highly polymorphic population displayed also high variability in the CAG sequence, featured by loss of the anchor CAA interruption(s). In addition, large ANs showed germinal and somatic instability. Our study also includes related genotypic, genealogical and haplotypic data and provides substantial evidence with regard to the role of large and intermediate alleles in the generation of pathological EAs.

Molecular epidemiology of spinocerebellar ataxias in Cuba: insights into SCA2 founder effect in Holguin.

The objective of this study was to determine the prevalence of hereditary ataxias in Cuba, with a special focus on the clinical and molecular features of SCA2. Clinical assessments were performed by neurological examinations and application of the SARA scale. Molecular analyses of genes SCA1-3, SCA6, SCA17 and DRPLA identified 753 patients with SCA and 7173 asymptomatic relatives, belonging to 200 unrelated families. 86.79% of all SCA patients were affected with SCA2. In the Holguin province, the average population prevalence of SCA2 is 40.18x10(5) inhabitants, with the remarkable figure of 141.66x10(5) in the Baguanos municipality. The high prevalence of the SCA2 mutation in Holguin reflects most likely a founder effect. The stabilization of the prevalence along time suggests the existence of premutated chromosomes with pure CAG, acting as reservoir for further expansions. CAG repeat length correlated inversely with age at onset, accounting for 80% of the variability. Genetic anticipation was observed in the 80% of transmissions. Repeat instability was greater in paternal transmissions whereas CAG expansions without anticipation was observed in 10.97% suggesting the effect of CAA interruptions in the CAG segment, which decrease the toxicity of the abnormal ataxin-2, and/or other protective factors.

Saccade velocity is controlled by polyglutamine size in spinocerebellar ataxia 2.

We assessed maximal saccade velocity (MSV) in 82 spinocerebellar ataxia type 2 (SCA2) patients and 80 controls, correlating it to disease duration, polyglutamine expansion size, age at onset, ataxia score, age, and sex. Little overlap with normal values was found even at earliest stages. Stepwise linear regression analysis showed that 60-degree MSV was strongly influenced by polyglutamine size and less by disease duration, whereas the reverse was found for ataxia score. Saccade velocity thus is a sensitive, quite specific, and objective endophenotype, useful to search polyglutamine modifier genes.