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Ataxia-telangiectasia (AT) is a rare genetic disorder leading to neurological defects, telangiectasias, and immunodeficiency. We aimed to study the clinical and immunological features of Latin American patients with AT and analyze factors associated with mortality. Referral centers from 9 Latin American countries participated in this retrospective cohort study, and 218 patients were included. Median (IQR) ages at symptom onset and diagnosis were 1.0 (1.0-2.0)  and 5.0 (3.0-8.0) years, respectively. Most patients presented recurrent airway infections, which was significantly associated with IgA deficiency. IgA deficiency was observed in 60.8% of patients and IgG deficiency in 28.6%. T- and B-lymphopenias were also present in most cases. Mean survival was 24.2 years, and Kaplan-Meier 20-year-survival rate was 52.6%, with higher mortality associated with female gender and low IgG levels. These findings suggest that immunologic status should be investigated in all patients with AT.

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Ataxia-telangiectasia (A-T) is a disease caused by mutations in the ATM gene (11q22.3-23.1) that induce neurodegeneration Sasihuseyinoglu AS et al.  Pediatr Allergy Immunol Pulmonol 31(1):9-14, 2018, Teive HAG et al. Parkinsonism Relat Disord 46:3-8, 2018. Clinically, A-T is characterized by ataxia, mucocutaneous telangiectasia, immunodeficiency, and malignancy. Movement disorders have been the most described and well-studied symptoms of A-T. Other studies have reported visuospatial processing disorders, executive function disorders and emotional regulation disorders, which are clinical manifestations that characterize cerebellar cognitive affective syndrome (CCAS) Choy KR et al. Dev Dyn 247(1):33-46, 2018. To describe the neurocognitive and emotional state of pediatric patients with ataxia-telangiectasia and to discuss whether they have cerebellar cognitive affective syndrome. This observational, cross-sectional, and descriptive study included 9 patients with A-T from May 2019 to May 2021. A complete medical history was retrieved, and tests were applied to assess executive functions, visual-motor integration and abilities, language, psychological disorders, and ataxia. Six girls and 3 boys agreed to participate. The age range was 6 to 14 years. The participants included five schoolchildren and four teenagers. Eight patients presented impaired executive functioning. All patients showed some type of error in copying and tracing (distortion) in the performance of visual perceptual abilities. Emotional disorders such as anxiety and depression were observed in six patients. Eight patients presented with dyslalia and impairments in word articulation, all patients presented with ataxia, and seven patients used a wheelchair. All patients presented symptoms consistent with CCAS and had variable cognitive performance.

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Background: The plant immune response to DNA is highly self/nonself-specific. Self-DNA triggered stronger responses by early immune signals such as H2O2 formation than nonself-DNA from closely related plant species. Plants lack known DNA receptors. Therefore, we aimed to investigate whether a differential sensing of self-versus nonself DNA fragments as damage- versus pathogen-associated molecular patterns (DAMPs/PAMPs) or an activation of the DNA-damage response (DDR) represents the more promising framework to understand this phenomenon. Results: We treated Arabidopsis thaliana Col-0 plants with sonicated self-DNA from other individuals of the same ecotype, nonself-DNA from another A. thaliana ecotype, or nonself-DNA from broccoli. We observed a highly self/nonself-DNA-specific induction of H2O2 formation and of jasmonic acid (JA, the hormone controlling the wound response to chewing herbivores) and salicylic acid (SA, the hormone controlling systemic acquired resistance, SAR, to biotrophic pathogens). Mutant lines lacking Ataxia Telangiectasia Mutated (ATM) or ATM AND RAD3-RELATED (ATR) - the two DDR master kinases - retained the differential induction of JA in response to DNA treatments but completely failed to induce H2O2 or SA. Moreover, we observed H2O2 formation in response to in situ-damaged self-DNA from plants that had been treated with bleomycin or SA or infected with virulent bacteria Pseudomonas syringae pv. tomato DC3000 or pv. glycinea carrying effector avrRpt2, but not to DNA from H2O2-treated plants or challenged with non-virulent P. syringae pv. glycinea lacking avrRpt2. Conclusion: We conclude that both ATM and ATR are required for the complete activation of the plant immune response to extracellular DNA whereas an as-yet unknown mechanism allows for the self/nonself-differential activation of the JA-dependent wound response.

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BACKGROUND: Ataxia-telangiectasia (A-T) is a DNA repair disorder characterized by changes in several organs and systems. Advances in clinical protocols have resulted in increased survival of A-T patients, however disease progression is evident, mainly through metabolic and liver changes. OBJECTIVE: To identify the frequency of significant hepatic fibrosis in A-T patients and to verify the association with metabolic alterations and degree of ataxia. METHODS: This is a cross-sectional study that included 25 A-T patients aged 5 to 31 years. Anthropometric data, liver, inflammatory, lipid metabolism and glucose biomarkers (oral glucose tolerance test with insulin curve-OGTT) were collected. The Cooperative Ataxia Rating Scale was applied to assess the degree of ataxia. The following were calculated: Homeostasis Model Assessment-Insulin Resistance, Homeostasis Model Assessment-Adiponectin (HOMA-AD), Matsuda index, aspartate aminotransferase (AST): platelet ratio index, nonalcoholic fatty liver disease fibrosis score and BARD score. Liver ultrasonography and transient liver elastography by FibroScan® were performed. RESULTS: Significant hepatic fibrosis was observed in 5/25 (20%). Patients in the group with significant hepatic fibrosis were older (p < 0.001), had lower platelet count values (p = 0.027), serum albumin (p = 0.019), HDL-c (p = 0.013) and Matsuda index (p = 0.044); and high values of LDL-c (p = 0.049), AST (p = 0.001), alanine aminotransferase (p = 0.002), gamma-glutamyl transferase (p = 0.001), ferritin (p = 0.001), 120-min glycemia by OGTT (p = 0.049), HOMA-AD (p = 0.016) and degree of ataxia (p = 0.009). CONCLUSIONS: A non-invasive diagnosis of significant hepatic fibrosis was observed in 20% of A-T patients associated with changes in liver enzymes, ferritin, increased HOMA-AD, and the severity of ataxia in comparison with patients without hepatic fibrosis.

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La Ataxia-Telangiectasia (AT) es una rara enfermedad de herencia autosómica recesiva y de afección multisistémica, caracterizada por ataxia progresiva, inmunodeficiencia variable con infecciones recurrentes, riesgo incrementado de neoplasias con o sin telangiectasias óculo-cutáneas. La AT es causada por variantes patogénicas bialélicas en el gen ATM. Su diagnóstico se basa en la sospecha de un cuadro clínico compatible, niveles elevados de alfafetoproteína, atrofia cerebelosa y estudios genéticos. No existe tratamiento curativo de AT y su manejo se basa en medidas de soporte y prevención de complicaciones y asesoramiento genético. En esta revisión, actualizamos la epidemiología, manifestaciones clínicas, diagnóstico y tratamiento de AT incluyendo una búsqueda de casos publicados en el Perú.

Ataxia-Telangiectasia (AT) is a rare autosomal recessive disease with multisystemic involvement, characterized by slowly progressive ataxia, variable immunodeficiency with recurrent infections, increased risk of neoplasms with or without oculocutaneous telangiectasias. AT is caused by biallelic pathogenic variants within the ATM gene. Its diagnosis is based on suspicion of a compatible clinical symptomatology, increased levels of alpha-fetoprotein, cerebellar atrophy, and genetic testing. There is no curative treatment for AT and its management is based on supportive and preventive measures of eventual complications and genetic counseling. This review updates the epidemiology, clinical manifestations, diagnosis, and treatment of AT, including a search for cases published in Peru.

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INTRODUCTION: Ataxia-Telangiectasia (A-T) is a multi-system disorder that may be associated with endocrine changes, oxidative stress in addition to inflammation. Studies suggest that selenium is a trace element related to protection against damage caused by oxidative stress. OBJECTIVE: To describe the plasma levels of selenium and erythrocyte glutathione peroxidase activity in A-T patients and to relate them to oxidative stress and lipid status biomarkers. METHODS: This is a cross-sectional and controlled study evaluating 22 A-T patients (age median, 12.2 years old) matched by gender and age with 18 healthy controls. We evaluated: nutritional status, food intake, plasma selenium levels, erythrocyte glutathione peroxidase activity, lipid status, inflammation and oxidative stress biomarkers. RESULTS: Adequate levels of selenium were observed in 24/36 (66.7%) in this evaluated population. There was no statistically significant difference between the groups in selenium levels [47.6 µg/L (43.2-57.0) vs 54.6 (45.2-62.6) µg/dL, p = 0.242]. Nine of A-T patients (41%) had selenium levels below the reference value. The A-T group presented higher levels of LDL-c, non-HDL-c, oxidized LDL, Apo B, Apo-B/Apo-A-I1, LDL-c/HDL-c ratio, malondialdehyde [3.8 µg/L vs 2.8 µg/L, p = 0.029] and lower Apo-A-I1/HDL-c and glutathione peroxidase activity [7300 U/L vs 8686 U/L, p = 0.005]. Selenium levels were influenced, in both groups, independently, by the concentrations of oxidized LDL, malonaldehyde and non-HDL-c. The oxidized LDL (AUC = 0.849) and ALT (AUC = 0.854) were the variables that showed the greatest discriminatory power between groups. CONCLUSION: In conclusion, we observed the presence of selenium below the reference value in nearly 40% and low GPx activity in A-T patients. There was a significant, inverse and independent association between selenium concentrations and oxidative stress biomarkers. Those data reinforce the importance of assessing the nutritional status of selenium in those patients.

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Neste artigo relatamos a terapia nutricional de um paciente com ataxia-telangiectasia (A-T) utilizando a gastrostomia (GTM) como via alternativa para alimentação. Paciente do sexo masculino, 13 anos de idade, com diagnóstico clínico de A-T aos 6 anos. Aos 8 anos e 7 meses o paciente foi identificado com risco nutricional (ZIMC/I: -1,67). Após 1 ano, evoluiu de forma desfavorável (ZIMC/I: -2,51) apesar da intervenção nutricional, sendo indicada a GTM aos 9 anos e 11 meses. No entanto, em decorrência da dificuldade de aceitação dos pais, o procedimento foi realizado somente quando o adolescente completou 11 anos e 7 meses. Inicialmente foi prescrita para oferta pela GTM dieta enteral normocalórica e normoproteica, correspondendo a 45,8% da necessidade energética diária. Após um mês, com estabilidade metabólica, houve a transição para uma dieta enteral hipercalórica e hiperproteica, fornecendo 91,6% da necessidade energética diária. Após 6 meses com a GTM, verificou-se ganho de peso total de 3,3 Kg (ZIMC/I -2,97), após 1 ano de 4,7 Kg (ZIMC/I -2,59), e após 1 ano e 9 meses de 6,7 Kg (ZIMC/I -2,63). Apesar da desnutrição nos pacientes com A-T ter origem multifatorial, o uso da GTM como via alternativa para alimentação por esse paciente resultou em uma evolução favorável dos seus indicadores antropométricos, sendo relatadas poucas intercorrências com a sua utilização. Portanto, sugere-se que pacientes com A-T devam ser monitorados periodicamente por equipe multiprofissional visando à identificação precoce de potenciais agravos.

In this article we report the nutritional therapy of a patient with ataxia-telangiectasia (A-T) using percutaneous endoscopic gastrostomy (PEG) as an alternative way of feeding. The patient was a 13-year-old male diagnosed with A-T at the age of 6 years. At 8 years and 7 months, the patient was at nutritional risk (body mass index z-score [BMIZ]: -1.67). After 1 year, he had an unfavorable evolution (BMIZ: -2.51), despite nutritional intervention; then, a PEG was indicated when he was 9 years and 11 months. However, due to the difficulty of parental acceptance, the procedure was performed when the adolescent was 11 years and 7 months. At first, a standard energy and protein enteral formula was prescribed, reaching 45.8% of his daily energy requirement. After 1 month, with metabolic stability, there was a transition to a high-energy and protein enteral formula providing 91.6% of his daily energy requirement. After 6 months of PEG placement, the patient had a total body weight gain of 3.3 kg (BMIZ: -2.97); subsequently, body weight increased by 4.7 kg (BMIZ: -2.59) after 1 year, and by 6.7 kg (BMIZ: -2.63) after 1 year and 9 months. Despite the multifactorial origin of malnutrition in A-T patients, PEG placement as an alternative way of feeding for this patient resulted in favorable evolution of his anthropometric indicators, and only a few complications were reported with its use. Therefore, it is suggested that patients with A-T should be monitored periodically by a multidisciplinary team for early identification of potential damages.

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INTRODUCTION AND OBJECTIVES: Vitamin D plays a role in the immune system, however studies regarding this are scarce. This study aimed to evaluate the nutritional status of vitamin D in patients with Common Variable Immunodeficiency (CVID) or Ataxia-Telangiectasia (A-T) and to relate it to body composition, inflammatory and bone metabolism markers. PATIENTS AND METHODS: This is a cross-sectional and controlled study involving 24 patients of both sexes (59.3% male), aged 8-56 years, with CVID (n=15) or A-T (n=9). The following variables were evaluated: body mass index (BMI), 25-hydroxyvitamin D (25 (OH) D), hepatic profile, parathormone, calcium, phosphorus, alkaline phosphatase, interleukin 6 and high-sensitivity C-reactive protein. RESULTS: The median age was 26.0 years. A deficiency of 25 (OH) D was found in four A-T patients (44%) and two CVID patients (13%). Nine patients with CVI (60%) and six with A-T (66.7%) were overweight and underweight, respectively. There was a negative correlation between vitamin D and fat mass in the CVID group, and vitamin D and BMI in the A-T group. Vitamin D was negatively associated with the percentage of total fat among the patients (ß - 0.842, 95% CI: -1.5-0.17, p=0.015), R2=0.21, after adjusting for sex and age. CONCLUSION: Vitamin D deficiency occurred in a quarter of the patients although there was no difference between the patient and the control group; without association with bone and inflammation biomarkers. The percentage of fat and BMI were negatively associated with the concentrations of 25 (OH) D.

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Introdução: A tomada de decisão compartilhada é uma estratégia centrada na pessoa, procurando alinhar a comunicação entre profissionais da saúde e pacientes, conjuntamente com as preferências, valores e objetivos dos indivíduos Objetivo: Correlacionar os achados clínicos da disartria, disfagia e cognição com o processo de tomada de decisão em saúde em um paciente com diagnóstico molecular confirmado de Ataxia Telangiectasia em cuidados paliativos em fase terminal. Método: Foi realizada avaliação clínica fonoaudiológica da disartria, disfagia e cognição. À partir dos resultados apresentados na avaliação, foram abordados princípios e diretrizes do processo de tomada de decisão em saúde, a fim de auxiliar na definição do processo terapêutico em pacientes em cuidados paliativos. Resultados: Paciente apresentou disartria atáxica e disfagia orofaríngea moderada a grave, porém apesar do risco significativo de aspiração laríngea para todas as consistências alimentares, demonstrou forte desejo em manter alimentação via oral exclusiva. Com relação à cognição paciente apresentou funções cognitivas de acordo com a normalidade para idade e escolaridade. Por meio de um processo de escolha informada, discussão multidisciplinar e baseando-se em princípios da tomada de decisão compartilhada em saúde, optou-se por priorizar o desejo do paciente e indicou-se alimentação via oral. Conclusão: Partindo do processo de tomada de decisão compartilhada e buscando minimizar o sofrimento de pacientes em cuidados paliativos, o fonoaudiólogo deve assumir uma nova perspectiva às decisões terapêuticas a fim de favorecer e envolver o paciente e seus familiares desde o início do diagnóstico até as decisões de fim de vida.

Introduction: Shared decision making is a person-centered strategy, seeking to align communication between health professionals and patients, along with individuals' preferences, values and goals. Objective: To correlate the clinical findings of dysarthria, dysphagia and cognition with the health decision-making process of a patient with confirmed molecular diagnosis of Ataxia Telangiectasia, in end-stage palliative care. Method: An evaluation of dysarthria, dysphagia and cognition was performed by a speech language pathologist. Based on the results which presented in the evaluation, principles and guidelines of the health decision-making process were addressed, in order to help define the therapeutic process for patients in palliative care. Results: The patient presented ataxic dysarthria and moderate to severe oropharyngeal dysphagia. However, despite a significant risk of laryngeal aspiration for all food consistencies, the patient expressed a strong desire to maintain exclusive oral feeding. With regard to cognition, the patient presented normal cognitive functions for his age bracket and education level. Through a process of informed choice and multidisciplinary discussion, and based on principles of shared decision-making in health, we chose to prioritize the patient's desire and to support oral feeding. Conclusion: Starting from the shared decision-making process and seeking to minimize the suffering of patients in palliative care, the speech language pathologist must take a new perspective on therapeutic decisions in order to favor and involve the patient and his relatives from the beginning of the diagnosis up to end-of-life decisions.

Introduction: La toma de decisiones compartida es una estrategia centrada en la persona, buscando alinear la comunicación entre profesionales de la salud y pacientes, junto con las preferencias, valores y objetivos de los individuos. Objetivo: Correlacionar los hallazgos clínicos de la disartria, disfagia y cognición con el proceso de toma de decisión en salud en un paciente con diagnóstico molecular confirmado de Ataxia Telangiectasia en cuidados paliativos en fase terminal. Método: Se realizó una evaluación clínica fonoaudiológica de la disartria, disfagia y cognición. A partir de los resultados presentados en la evaluación se abordaron principios y directrices del proceso de toma de decisión en salud, a fin de auxiliar en la definición del proceso terapéutico en pacientes en cuidados paliativos. Resultados: Paciente presentó disartria atáxica y disfagia orofaríngea moderada a grave, pero a pesar del riesgo significativo de aspiración laríngea para todas las consistencias alimenticias, demostró fuerte deseo en mantener alimentación oral exclusiva. Con respecto a la cognición paciente presentó funciones cognitivas de acuerdo con la normalidad para edad y escolaridad. Por medio de un proceso de elección informada, discusión multidisciplinaria y basándose en principios de la toma de decisión compartida en salud, se optó por priorizar el deseo del paciente y se indicó alimentación oral. Conclusión: Partiendo del proceso de toma de decisión compartida y buscando minimizar el sufrimiento de pacientes en cuidados paliativos, el fonoaudiólogo debe asumir una nueva perspectiva a las decisiones terapéuticas a fin de favorecer e involucrar al paciente ya sus familiares desde el inicio del diagnóstico hasta las decisiones de fin de vida.

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Objective To describe the frequency of mutations in DNA-repair genes in a southwestern Colombian population. Methods We have designed an observational study, including 162 people from all ages from southwest Colombia. We have extracted and collected their DNA in filters. We have immersed the DNA in a phosphate buffer along with DNeasy package (Thermo Fisher Scientific, Waltham, MA, USA). The preparation process was with the TruSeq Exome Library Prep (Illumina, Inc. San Diego, CA, USA), then the obtained libraries were normalized with TruSeq Rapid Exome (Illumina, Inc. San Diego, CA, USA). We sequenced the full exome and identified the variants associated with 12 genes (ataxia telangiectasia mutated [ATM], BRCA1 DNA repair associated [BRCA1], BRCA2 DNA repair associated [BRCA2], checkpoint kinase 2 [CHEK2], epithelial cell adhesion molecule [EPCAM], homeobox protein Hox-B13 [HOXB13], mutS homolog 1, 2 and 6 [MLH1, MSH2, MSH6], nibrin [NBN], PMS1 homolog 2, mismatch repair system component [PMS2], and tumor protein p53 [TP53]). Descriptive statistics were performed with the R software (The R Foundation for Statistical Computing, Vienna, Austria). Results A total of 7,315,466 pieces of data were sequenced in this population. The most frequently mutated genes were ATM (1,221 pieces of data; 13.2%), BRCA1 (1,178 pieces of data; 12.8%), BRCA2 (1,484 pieces of data; 16.12%), and NBN (965 pieces of data; 10.42%). The most common single nucleotide polymorphisms (SNPs) in these 12 genes were the following: BRCA2 (rs169547, rs206075, rs206076); ATM (rs659243, rs228589); TP53 (rs1625895, rs1042522, rs1642785); PMS2 (rs2228006, rs1805319); NBN (rs709816); and MSH6 (rs3136367) Conclusion The BRCA2, ATM, BRCA1 and NBN DNA-repair genes were the most frequently mutated in this southwestern Colombian Population

Objetivo Describir la frecuencia de las mutaciones en los genes de reparación del ADN en una población del suroccidente de Colombia. Métodos Diseñamos un estudio observacional que incluyó a 162 personas del suroccidente de Colombia de todas las edades. Hemos extraído y recogido el ADN en filtros. Los sumergimos en tampón fosfato junto con el paquete DNeasy (Thermo Fisher Scientific, Waltham, MA, EEUU). El proceso de preparación fue realizado con TruSeq Exome Library Prep (Illumina, Inc. San Diego, CA, EEUU); luego, las bibliotecas obtenidas se normalizaron con TruSeq Rapid Exome (Illumina, Inc. San Diego, CA, USA). Secuenciamos el exoma completo e identificamos las variantes asociadas a doce genes (ataxia telangiectasia mutated [ATM], BRCA1 DNA repair associated [BRCA1], BRCA2 DNA repair associated [BRCA2], checkpoint kinase 2 [CHEK2], epithelial cell adhesion molecule [EPCAM], homeobox protein Hox-B13 [HOXB13], mutS homolog 1, 2 and 6 [MLH1, MSH2, MSH6], nibrin [NBN], PMS1 homolog 2, mismatch repair system component [PMS2], y tumor protein p53 [TP53]). La estadística descriptiva se realizó en el programa R (The R Foundation for Statistical Computing, Viena, Austria). Resultados Un total de 7.315.466 datos fueron secuenciados en esta población. Los genes más frecuentemente mutados fueron el ATM, con 1.221 datos (13,2%), el BRCA1, con 1.178 datos (12,8%), el BRCA2, con 1.484 datos (16,12%) y el NBN, con 965 datos (10,42%). Los polimorfismos de un solo nucleótido (PSN) más comunes en estos 12 genes fueron los siguientes: BRCA2 (rs169547, rs206075, rs206076); ATM (rs659243, rs228589); TP53 (rs1625895, rs1042522, rs1642785); PMS2 (rs2228006, rs1805319); NBN (rs709816) y MSH6 (rs3136367) Conclusión Los genes de reparación de ADN BRCA2, ATM, BRCA1 NBN fueron los más frecuentemente mutados en esta población del suroccidente de Colombia.

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Ataxi A-T elangiectasia (AT) is a multisystem, complex and rare disease inherited in an autosomal recessive manner. Homozygous individuals have a variety of pathological manifestations, however, heterozygotes only present a higher risk of developing cancer. We evaluated the background levels of DNA damage (basal damage) and cell response to bleomycin or ionizing radiation using Comet assay and the cytokinesis-block micronucleus (CBMN) test in individuals with AT, their parents and controls. To evaluate DNA repair, the challenge experiment with ionizing radiation was performed using Comet assay, and different recovery times were evaluated. Results showed that basal MN frequencies differ between patients, parents and controls. Meanwhile, using the Comet assay, the results from the basal analysis do not differ between the groups, but monitoring the kinetics of DNA repair, we verified that the group of patients showed a delay in repair, compared to controls. Another finding was the nuclear bud (NBUD) frequency: spontaneous and induced cell cultures (with bleomycin and radiation) showed clear differences between patients, parents and controls. The CBMN assay and repair measurement with the Comet assay can help in the diagnosis of AT patients and ATM gene carriers, as complementary methods. The use of genomic instability evaluation techniques for the identification of the heterozygotes in families, where at least one member is affected, may be of great clinical importance.

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La ataxia-telangiectasia es un trastorno autosómico recesivo, caracterizado por la presencia de telangiectasias oculocutáneas, ataxia cerebelosa progresiva, inmunodeficiencia e infecciones recurrentes. Además, está relacionado con neoplasias del sistema retículo-endotelial y trastornos inmunológicos. El objetivo de la presentación es destacar el papel del dermatólogo en este tipo de trastornos neurocutáneos, así como la importancia del seguimiento a largo plazo.

Ataxia telangiectasia is an autosomal recessive disorder characterized by oculocutaneous telangiectasia, progressive cerebellar ataxia, immunodeficiency, and recurrent infections. Besides, it is related to reticuloendothelial system neoplasms and immune disorders. The aim of this presentation is to emphasize the role of the Dermatologist in this type of neurocutaneous disorders and the importance of long-term follow up.

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BACKGROUND: Ataxia-telangiectasia (AT) is a well-known primary immunodeficiency with recurrent sinopulmonary infections and variable abnormalities in both the humoral and cellular immune system. Dysfunctions in immunoglobulin production, reduced number of B cells, and B-cell receptor excision circles copies have been reported. We aimed to understand the immunological mechanisms involving the humoral compartment in AT patients by analysing peripheral blood B cells subsets, B-T lymphocyte cooperation through the expression of CD40 and CD40 ligand (CD40L), and cytokines involved in class-switch recombination production. METHODS: We compared the proportion of B-cell subsets, the expression of CD40/CD40L, and the plasma levels of IL-6 and IFN-γ of 18 AT patients and 15 healthy age-sex-matched controls using flow cytometry. RESULTS: We found that some steps in peripheral B cell development were altered in AT with a pronounced reduction of cell-surface CD40 expression. The proportions of transitional and naïve-mature B cells were reduced, whereas CD21-low, natural effector memory, IgM-only memory, and IgG atypical memory B cells were present in a higher proportion. CONCLUSIONS: These findings revealed a disturbed B-cell homeostasis with unconventional maturation of B lymphocyte memory cells, which can explain the consequent impairment of humoral immunity.

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OBJECTIVE: To evaluate the carotid intima-media complex (CIMC) thickness and lipid metabolism biomarkers associated with cardiovascular risk (CR) in parents of patients with ataxia-telangiectasia and verify an association with gender. METHOD: A cross-sectional and controlled study with 29 ATM heterozygotes and 14 healthy controls. Biochemical tests and CIMC thickness measurement were performed. RESULTS: The mean CIMC measurement in heterozygous ATM was 0.72 ± 0.1 mm (minimum: 0.5 mm and maximum: 1.0 mm). Noticed high percentage of amounts above 75 percentile compared to the population referential (16 [76.2%]), without any significant statistical differences between the female and the male gender (11/15 [73.3%] vs. 5/6 [83.3%]; p=0.550). The comparison between heterozygous and controls, stratified by gender, showed that in heterozygous ATMs, women had higher concentrations of HDL-c compared to men, as well as higher values of hs-CRP in relation to the control women. In heterozygous ATMs, stratified by gender, the correlation between HDL-c and hs-CRP was inversely proportional and stronger among women, with a tendency to statistical significance. CONCLUSION: Heterozygous ATMs did not differ from controls in relation to the biomarkers studied related to CR. However, most of them presented increased CIMC, independent predictor of death, risk for myocardial infarction and stroke, compared to the referential for the same age group. This finding suggests CR in the heterozygous ATM and shows to the need to monitor CIMC thickness and nutritional orientations.

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Summary Objective: To evaluate the carotid intima-media complex (CIMC) thickness and lipid metabolism biomarkers associated with cardiovascular risk (CR) in parents of patients with ataxia-telangiectasia and verify an association with gender. Method: A cross-sectional and controlled study with 29 ATM heterozygotes and 14 healthy controls. Biochemical tests and CIMC thickness measurement were performed. Results: The mean CIMC measurement in heterozygous ATM was 0.72 ± 0.1 mm (minimum: 0.5 mm and maximum: 1.0 mm). Noticed high percentage of amounts above 75 percentile compared to the population referential (16 [76.2%]), without any significant statistical differences between the female and the male gender (11/15 [73.3%] vs. 5/6 [83.3%]; p=0.550). The comparison between heterozygous and controls, stratified by gender, showed that in heterozygous ATMs, women had higher concentrations of HDL-c compared to men, as well as higher values of hs-CRP in relation to the control women. In heterozygous ATMs, stratified by gender, the correlation between HDL-c and hs-CRP was inversely proportional and stronger among women, with a tendency to statistical significance. Conclusion: Heterozygous ATMs did not differ from controls in relation to the biomarkers studied related to CR. However, most of them presented increased CIMC, independent predictor of death, risk for myocardial infarction and stroke, compared to the referential for the same age group. This finding suggests CR in the heterozygous ATM and shows to the need to monitor CIMC thickness and nutritional orientations.

Resumo Objetivo: Avaliar a espessura do complexo médio-intimal da carótida (CMIC) e os biomarcadores do metabolismo lipídico associados ao risco cardiovascular (RC) em pais de pacientes com ataxia-telangiectasia (AT) e verificar associação com gênero. Método: Estudo transversal prospectivo e controlado com 29 ATM heterozigotos e 14 controles saudáveis. Foram realizados exames bioquímicos e a espessura do CMIC por ultrassonografia. Resultados: A média da medida do CMIC nos ATM heterozigotos foi de 0,72± 0,1 mm (mínimo: 0,5 mm e máximo: 1,0 mm). Observou-se elevado percentual de valores acima do percentil 75 em relação ao referencial populacional (16 [76,2%]), sem diferença estatisticamente significante entre o gênero feminino e o masculino (11/15 [73,3%] vs. 5/6 [83,3%]; p=0.550). A comparação entre os ATM heterozigotos e os controles, estratificados por gênero, mostrou que, nos ATM heterozigotos, as mulheres tinham maiores concentrações de HDL-c em comparação aos homens, e valores mais elevados de PCR-us em relação às mulheres controle. Nos ATM heterozigotos, estratificando segundo gênero, a correlação entre HDL-c e PCR-us foi inversamente proporcional e mais forte entre as mulheres, com tendência à significância estatística. Conclusão: Os ATM heterozigotos não diferiram dos controles em relação aos biomarcadores estudados relacionados ao RC. Entretanto, a maioria deles apresentou aumento na espessura do CMIC, preditor independente de morte, risco para infarto do miocárdio e AVC, quando comparado ao referencial para a mesma faixa etária. Esse achado sugere RC nos ATM heterozigotos e aponta para a necessidade de monitoramento da espessura do CMIC e de orientações nutricionais.

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DNA is constantly being damaged, either by endogenous or exogenous genotoxins. In that regard, DNA repair activities are essential for maintaining genomic stability and to life itself. Mutations in genes encoding DNA repair proteins cause severe human syndromes, but DNA repair defects have also been linked to several other diseases, notably to cancer and normal aging. Recently, new evidence has emerged indicating that some DNA repair diseases display mitochondrial and metabolic dysfunction through mechanisms that are yet being uncovered. These results suggest that mitochondria play an import role in the DNA damage response pathways and that damage accumulation may lead to mitochondrial dysfunction via metabolic imbalance and mitophagy impairment. Here we review the recent findings linking mitochondrial impairment and cell death to DNA damage accumulation in the context of DNA repair defects. In addition, the general involvement of DNA damage in cellular dysfunction suggests that these phenomena may be also involved in other human pathologies in which mitochondrial dysfunction and metabolic disruption play causative roles.

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La ataxia-telangiectasia es una entidad caracterizada por un cuadro de ataxia cerebelosa progresiva, telangiectasias, defectos inmunológicos y una mayor tendencia al desarrollo de tumores malignos. La mutación genética responsable (ataxia-telangiectasia mutada) parece jugar un papel importante en la función celular normal y el remodelado cardiovascular. Se describe la aparición de una arritmia maligna en un paciente de 14 años con un diagnóstico de ataxia-telangiectasia, en remisión completa de linfoma no Hodgkin B de alto grado. Consultó en el Servicio de Urgencias Pediátricas por episodios de presíncope, y se observó, al ingresar, bloqueo auriculoventricular completo que evolucionó hacia asistolia, por lo que requirió la colocación de un marcapasos definitivo. Las dosis acumuladas de fármacos cardiotóxicos recibidos fueron de bajo riesgo. Sin embargo, es posible que esta enfermedad degenerativa crónica afecte con el tiempo al tejido de citoconducción. En la bibliografía revisada, no existen o se desconocen reportes previos de arritmias malignas en pacientes con ataxia-telangiectasia.

Ataxia-telangiectasia is a disorder characterized by cerebellar ataxia, telangiectasia, immunodeficiency, and increased predisposition to cancer susceptibility. Mutations in the ataxia telangiectasia mutated gene seem to play an important role in normal cell function and in cardiovascular remodeling. We report a case of a 14-year-old boy with ataxia-telangiectasia and high-grade B-non-Hodgkin lymphoma who remained in continuous complete remission after chemotherapy and who was admitted into our Emergency Room presenting with episodes of presyncope. At admission he presented a complete atrioventricular block that evolved into asystole and required placement of a pacemaker. Cumulative cardiotoxic drugs received were at low risk. However, it is possible that this chronic degenerative disease may affect the cardiac conduction system over time. In the reviewed literature there are no or unknown reports of ataxia-telangiectasia with malignant cardiac arrhythmias.

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Ataxia-telangiectasia is a disorder characterized by cerebellar ataxia, telangiectasia, immunodeficiency, and increased predisposition to cancer susceptibility. Mutations in the ataxia telangiectasia mutated gene seem to play an important role in normal cell function and in cardiovascular remodeling. We report a case of a 14-year-old boy with ataxia-telangiectasia and high-grade B-non-Hodgkin lymphoma who remained in continuous complete remission after chemotherapy and who was admitted into our Emergency Room presenting with episodes of presyncope. At admission he presented a complete atrioventricular block that evolved into asystole and required placement of a pacemaker. Cumulative cardiotoxic drugs received were at low risk. However, it is possible that this chronic degenerative disease may affect the cardiac conduction system over time. In the reviewed literature there are no or unknown reports of ataxia-telangiectasia with malignant cardiac arrhythmias.

La ataxia-telangiectasia es una entidad caracterizada por un cuadro de ataxia cerebelosa progresiva, telangiectasias, defectos inmunológicos y una mayor tendencia al desarrollo de tumores malignos. La mutación genética responsable (ataxia-telangiectasia mutada) parece jugar un papel importante en la función celular normal y el remodelado cardiovascular. Se describe la aparición de una arritmia maligna en un paciente de 14 años con un diagnóstico de ataxia-telangiectasia, en remisión completa de linfoma no Hodgkin B de alto grado. Consultó en el Servicio de Urgencias Pediátricas por episodios de presíncope, y se observó, al ingresar, bloqueo auriculoventricular completo que evolucionó hacia asistolia, por lo que requirió la colocación de un marcapasos definitivo. Las dosis acumuladas de fármacos cardiotóxicos recibidos fueron de bajo riesgo. Sin embargo, es posible que esta enfermedad degenerativa crónica afecte con el tiempo al tejido de citoconducción. En la bibliografía revisada, no existen o se desconocen reportes previos de arritmias malignas en pacientes con ataxia-telangiectasia.

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INTRODUCTION: The ataxia telangiectasia syndrome (AT) is a genetic disease with an autosomal recessive inheritance pattern, with multisystem involvement and a broad clinical spectrum. It is caused by the mutation of the ATM gene, causing reduction or absence of the ATM proteinkinase, altering processes in the cell cycle, DNA repair and apoptosis. The objective of this article is to report the case of a patient with ataxia telangiectasia syndrome, caused by a mutation not previously reported in the literature. CASE REPORT: A 14 year-old patient native to Colombia, with classic clinical and phenotypical manifestations of AT syndrome, which started at 6 years of age with pondostatural alteration, recurrent respiratory infections, oculocutaneus telangiectasias and progressive neurological disorder that included: regression in her psychomotor development, ataxia and oculomotor apraxia. ATM gene sequencing is performed evidencing a homozygous mutation not reported in literature. DISCUSSION: In Latin America are sparse the number of reports of patients with ataxia telangiectasia and only few of these describe their molecular findings. Molecular studies allow the diagnosis and a better orientation in the management and prognosis of patients with neurodegenerative diseases. The report of undescribed molecular variants is of great importance to establish the etiology of such diseases in diverse population groups, such as the countries of Latin America.

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