Paciente varón de tres años con sibilancias y tos crónica / Three-Year-Old Male with Wheezing and Chronic Cough

Se presenta el caso de un niño de 3 años con diagnóstico de asma, rinitis alérgica, características craneofaciales dismórficas e infecciones respiratorias altas y bajas recurrentes, manejado como asma desde un inicio. Como parte del estudio de comorbilidades, se decide realizar una prueba del sudor que sale en rango intermedio y más tarde se encuentra una mutación, donde se obtiene un resultado positivo para una copia que se asocia a fibrosis quística. Se revisará el caso, así como el diagnóstico, clínica y tratamiento del síndrome metabólico relacionado con el regulador de conductancia transmembrana de fibrosis quística (CRMS).

We present the case of a 3-year-old boy with a diagnosis of asthma, allergic rhinitis, dysmorphic craniofacial characteristics and recurrent upper and lower respiratory infections, managed as asthma from the beginning. As part of the study of comorbidi-ties, it was decided to carry out a sweat test that came out in the intermediate range and later one mutation was found, where a positive result was obtained for a copy that is associated with cystic fibrosis. The case will be reviewed, as well as the diagnosis, symptoms and treatment of the metabolic syndrome related to the cystic fibrosis trans-membrane conductance regulator (CRMS).

Evolución clínico funcional de pacientes con fibrosis quística tratados con lumacaftor/ivacaftor en un centro pediátrico. Serie de casos / Clinical and functional course of patients with cystic fibrosis treated with lumacaftor/ivacaftor at a children's hospital. A case series

Los moduladores de la proteína reguladora transmembrana de fibrosis quística (CFTR) tratan el defecto de esta proteína. El objetivo es describir la evolución de niños con fibrosis quística tratados con lumacaftor/ivacaftor. Se trata de una serie de 13 pacientes de 6 a 18 años con ≥ 6 meses de tratamiento. Se analizaron el volumen espiratorio forzado en el primer segundo (VEF1), puntaje Z del índice de masa corporal (IMC), antibioticoterapia/año, antes del tratamiento y durante 24 meses posteriores. A los 12 meses (9/13) y 24 meses (5/13), la mediana de cambio del porcentaje del predicho VEF1 (ppVEF1) fue de 0,5 pp [-2-12] y 15 pp [8,7-15,2], y del puntaje Z de IMC de 0,32 puntos [-0,2-0,5] y 1,23 puntos [0,3-1,6]. El primer año (11/13) la mediana de días de uso de antibiótico disminuyó de 57 a 28 (oral) y de 27 a 0 (intravenoso). Dos niños evidenciaron eventos adversos asociados.

Cystic fibrosis transmembrane regulator (CFTR) modulators treat defective CFTR protein. Our objective is to describe the course of children with cystic fibrosis treated with lumacaftor/ivacaftor. This is a case series of 13 patients aged 6 to 18 years with ≥ 6 months of treatment. Forced expiratory volume in the first second (FEV1), body mass index (BMI) Z-score, antibiotic therapy/year, before treatment and for 24 months after treatment were analyzed. At 12 months (9/13) and 24 months (5/13), the median change in the percent predicted FEV1 (ppFEV1) was 0.5 pp (-2­12) and 15 pp (8.7­15.2) and the BMI Z-score was 0.32 points (-0.2­0.5) and 1.23 points (0.3­1.6). In the first year, in 11/13 patients, the median number of days of antibiotic use decreased from 57 to 28 (oral) and from 27 to 0 (intravenous). Two children had associated adverse events.

Enfermedad hepática en la fibrosis quística pediátrica. Una revisión de los conocimientos actuales / Cystic fibrosis liver disease in children ­ A review of our current understanding

La fibrosis quística, la segunda enfermedad genética más frecuente, es el resultado de una proteína de canal mutada, la CFTR, que secreta iones de cloro que fluidifican las secreciones. La esperanza de vida en los pacientes ha aumentado en años recientes gracias a mejoras en el tratamiento. No obstante, las complicaciones hepáticas son la tercera causa de muerte y la comprensión de su fisiopatología es aún deficiente. Se considera que la obstrucción biliar secundaria a la presencia de secreciones espesas conduce a la cirrosis. Sin embargo, el ácido ursodesoxicólico no ha modificado la historia natural. Además, la presencia de hipertensión portal en ausencia de cirrosis no puede ser explicada. Se ha propuesto el rol de la CFTR como modulador de tolerancia inmune, que explica la presencia de una inflamación portal persistente que culmina en fibrosis. El eje intestino-hígado tendría un rol importante en la presentación y la progresión de esta enfermedad

Cystic fibrosis is the second most common genetic disease in infancy. It is the result of a mutated channel protein, the CFTR, which secretes chloride ions, fluidifying secretions. Recent improvements in the treatment have increased life expectancy in these patients. Nevertheless, liver involvement remains the third cause of death. Unfortunately, our understating of the physiopathology is still deficient. Biliary obstruction secondary to the presence of thick secretions is considered to lead to cirrhosis. However, treatment with ursodeoxycolic acid has not changed the natural history. Furthermore, the presence of portal hypertension in the absence of cirrhosis cannot be explained. Recently, the role of CFTR as modulator of immune tolerance has been proposed, which could explain the presence of a persistent portal inflammation leading to fibrosis, and the gut-liver axis would also have a role in disease presentation and progression.

Actualización en fibrosis quística estándares de atención para pacientes con diagnóstico de fibrosis quística con terapia moduladora: informe de la Sociedad Europea de Fibrosis Quística 2023 / Standards of care for patients with a diagnosis of cystic fibrosis who are on modulator therapy: report of the European Fibrosis Cystic Society 2023

La fibrosis quística ha entrado en la era de la terapia específica con los moduladores, útiles en variantes genéticas definidas por estudio molecular, con resultados clínicos exitosos. Este es un resumen de la publicación reciente de la Sociedad Respiratoria Europea que establece los estándares de cuidado para los pacientes que reciben este tratamiento.

Cystic fibrosis has entered the era of specific therapy called modulators, useful in genetic variants defined by molecular study, with successful clinical results. This is a summary of the recent publication of the European Respiratory Society that establishes the standards of care for patients receiving this treatment.

Loss-of-function CFTR p.G970D missense mutation might cause congenital bilateral absence of the vas deferens and be associated with impaired spermatogenesis / 亚洲男科学杂志(英文版)

Congenital bilateral absence of the vas deferens (CBAVD) is observed in 1%-2% of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator (CFTR) mutations. CFTR is one of the most well-known genes related to male fertility. The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia (NOA). CFTR mutations are highly polymorphic and have established ethnic specificity. Compared with F508Del in Caucasians, the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis. However, whether p.G970D participates in male infertility remains unknown. Herein, a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA. Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation (4.1%, 5/122), excluding polymorphic sites. Furthermore, we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients. The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells. In spermatocyte GC-2(spd)ts (GC2) Cftr p.G965D cells, RNA splicing variants were detected and CFTR expression decreased, which may contribute to the phenotypes associated with impaired spermatogenesis. Thus, this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.

Novel mutation c.1210-3C > G in cis with a poly-T tract of 5T affects CFTR mRNA splicing in a Chinese patient with cystic fibrosis / 医学前沿

Cystic fibrosis (CF) is a rare autosomal recessive disease with only one pathogenic gene cystic fibrosis transmembrane conductance regulator (CFTR). To identify the potential pathogenic mutations in a Chinese patient with CF, we conducted Sanger sequencing on the genomic DNA of the patient and his parents and detected all 27 coding exons of CFTR and their flanking intronic regions. The patient is a compound heterozygote of c.2909G > A, p.Gly970Asp in exon 18 and c.1210-3C > G in cis with a poly-T of 5T (T5) sequence, 3 bp upstream in intron 9. The splicing effect of c.1210-3C > G was verified via minigene assay in vitro, indicating that wild-type plasmid containing c.1210-3C together with T7 sequence produced a normal transcript and partial exon 10-skipping-transcript, whereas mutant plasmid containing c.1210-3G in cis with T5 sequence caused almost all mRNA to skip exon 10. Overall, c.1210-3C > G, the newly identified pathogenic mutation in our patient, in combination with T5 sequence in cis, affects the CFTR gene splicing and produces nearly no normal transcript in vitro. Moreover, this patient carries a p.Gly970Asp mutation, thus confirming the high-frequency of this mutation in Chinese patients with CF.

Clinical and gene mutation features of cystic fibrosis: an analysis of 8 cases / 中国当代儿科杂志

OBJECTIVES@#To study the clinical features and gene mutation sites of children with cystic fibrosis (CF), in order to improve the understanding of CF to reduce misdiagnosis and missed diagnosis.@*METHODS@#A retrospective analysis was performed on the medical records of 8 children with CF who were diagnosed in Hebei Children's Hospital from 2018 to 2021.@*RESULTS@#Among the 8 children with CF, there were 5 boys and 3 girls, with an age of 3-48 months (median 8 months) at diagnosis, and the age of onset ranged from 0 to 24 months (median 2.5 months). Clinical manifestations included recurrent respiratory infection in 7 children, sinusitis in 3 children, bronchiectasis in 4 children, diarrhea in 8 children, fatty diarrhea in 3 children, suspected pancreatic insufficiency in 6 children, pancreatic cystic fibrosis in 1 child, malnutrition in 5 children, and pseudo-Bartter syndrome in 4 children. The most common respiratory pathogens were Pseudomonas aeruginosa (4 children). A total of 16 mutation sites were identified by high-throughput sequencing, multiplex ligation-dependent probe amplification, and Sanger sequencing, including 5 frameshift mutations, 4 nonsense mutations, 4 missense mutations, 2 exon deletions, and 1 splice mutation. CFTR mutations were found in all 8 children. p.G970D was the most common mutation (3 children), and F508del mutation was observed in one child. Four novel mutations were noted: deletion exon15, c.3796_3797dupGA(p.I1267Kfs*12), c.2328dupA(p.V777Sfs*2), and c.2950G>A(p.D984N).@*CONCLUSIONS@#p.G970D is the most common mutation type in children with CF. CF should be considered for children who have recurrent respiratory infection or test positive for Pseudomonas aeruginosa, with or without digestive manifestations or pseudo-Bartter syndrome.

Chloride and sodium ion concentrations in saliva and sweat as a method to diagnose cystic fibrosis / Dosagem da concentração dos íons cloreto e sódio na saliva e no suor para o reconhecimento de pacientes com fibrose cística

Abstract Objective: Cystic fibrosis diagnosis is dependent on the chloride ion concentration in the sweat test (≥ 60 mEq/mL - recognized as the gold standard indicator for cystic fibrosis diagnosis). Moreover, the salivary glands express the CFTR protein in the same manner as sweat glands. Given this context, the objective was to verify the correlation of saliva chloride concentration and sweat chloride concentration, and between saliva sodium concentration and sweat sodium concentration, in patients with cystic fibrosis and healthy control subjects, as a tool for cystic fibrosis diagnosis. Methods: There were 160 subjects enrolled: 57/160 (35.70%) patients with cystic fibrosis and two known CFTR mutations and 103/160 (64.40%) healthy controls subjects. Saliva ion concentration was analyzed by ABL 835 Radiometer® equipment and, sweat chloride concentration and sweat sodium concentration, respectively, by manual titration using the mercurimetric procedure of Schales & Schales and flame photometry. Statistical analysis was performed by the chi-squared test, the Mann -Whitney test, and Spearman's correlation. Alpha = 0.05. Results: Patients with cystic fibrosis showed higher values of sweat chloride concentration, sweat sodium concentration, saliva chloride concentration, and saliva sodium concentration than healthy controls subjects (p-value < 0.001). The correlation between saliva chloride concentration and sweat chloride concentration showed a positive Spearman's Rho (correlation coefficient) = 0.475 (95% CI = 0.346 to 0.587). Also, the correlation between saliva sodium concentration and sweat sodium concentration showed a positive Spearman's Rho = 0.306 (95% CI = 0.158 to 0.440). Conclusions: Saliva chloride concentration and saliva sodium concentration are candidates to be used in cystic fibrosis diagnosis, mainly in cases where it is difficult to achieve the correct sweat amount, and/or CFTR mutation screening is difficult, and/or reference methods for sweat test are unavailable to implement or are not easily accessible by the general population.

Resumo Objetivo: O diagnóstico da fibrose cística depende do valor da concentração de íons de cloreto no teste do suor (≥ 60 mEq/mL - reconhecido como o indicador-padrão para o diagnóstico da doença). Além disso, as glândulas salivares expressam a proteína RTFC igualmente às glândulas sudoríparas. Nesse contexto, nosso objetivo foi verificar a correlação da concentração de cloreto na saliva e a concentração de cloreto no suor e entre a concentração de sódio na saliva e a concentração de sódio no suor em pacientes com fibrose cística e indivíduos controles saudáveis, como uma ferramenta para diagnóstico de fibrose cística. Métodos: Contamos com a participação de 160 indivíduos [57/160 (35,70%) com fibrose cística e duas mutações no gene RTFC conhecidas e 103/160 (64,40%) indivíduos controles saudáveis]. A concentração de íons na saliva foi analisada pelo equipamento ABL 835 da Radiometer® e a concentração de cloreto no suor e sódio no suor, respectivamente, por titulação manual utilizando o método mercurimétrico de Schales & Schales e fotometria de chama. A análise estatística foi realizada pelo teste qui-quadrado, pelo teste de Mann-Whitney e pela correlação de Spearman. Alpha = 0,05. Resultados: Os pacientes com fibrose cística apresentaram maiores valores na concentração de cloreto no suor, concentração de sódio no suor, concentração de cloreto na saliva e concentração de sódio na saliva do que os indivíduos-controle saudáveis (valor de p < 0,001). A correlação entre as concentrações de cloreto na saliva e cloreto no suor mostrou Rho de Spearman (coeficiente de correlação) positivo = 0,475 (IC de 95% = 0,346 a 0,587). Além disso, a correlação entre concentração de sódio na saliva e concentração de sódio no suor mostrou Rho de Spearman positivo = 0,306 (IC de 95% = 0,158 a 0,440). Conclusões: A concentração de cloreto na saliva e a concentração de sódio na saliva são candidatas a ser usadas como diagnóstico de fibrose cística, principalmente em casos em que é difícil atingir a quantidade correta de suor, e/ou o exame da mutação RTFC é difícil e/ou o método de referência para o teste do suor não se encontra disponível ou não é de fácil acesso ao público em geral.

Evaluation of bone disease in patients with cystic fibrosis and end-stage lung disease / Avaliação de doença óssea em pacientes com fibrose cística e doença pulmonar terminal

ABSTRACT Objective: Bone disease is a common comorbidity in patients with cystic fibrosis (CF). We sought to determine risk factors and identify potential biochemical markers for CF-related bone disease (CFBD) in a unique cohort of CF patients with end-stage lung disease undergoing lung transplantation (LTx) evaluation. Methods: All of the CF patients who were evaluated for LTx at our center between November of 1992 and December of 2010 were included in the study. Clinical data and biochemical markers of bone turnover, as well as bone mineral density (BMD) at the lumbar spine and femoral neck, were evaluated. Spearman's rho and multivariate logistic regression analysis were used. Results: A total of 102 adult CF patients were evaluated. The mean age was 28.1 years (95% CI: 26.7-29.5), and the mean body mass index was 17.5 kg/m2 (95% CI: 17.2-18.2). Mean T-scores were −2.3 and −1.9 at the lumbar spine and femoral neck, respectively, being lower in males than in females (−2.7 vs. −2.0 at the lumbar spine and −2.2 vs. −1.7 at the femoral neck). Overall, 52% had a T-score of < −2.5 at either skeletal site. The homozygous Phe508del genotype was found in 57% of patients without osteoporosis and in 60% of those with low BMD. Mean T-scores were not particularly low in patients with severe CFTR mutations. Although the BMI correlated with T-scores at the femoral neck and lumbar spine, serum 25-hydroxyvitamin D and parathyroid hormone levels did not. Conclusions: CFBD is common in CF patients with end-stage lung disease, particularly in males and patients with a low BMI. It appears that CF mutation status does not correlate with CFBD. In addition, it appears that low BMD does not correlate with other risk factors or biochemical parameters. The prevalence of CFBD appears to have recently decreased, most likely reflecting increased efforts at earlier diagnosis and treatment.

RESUMO Objetivo: A doença óssea é uma comorbidade comum em pacientes com fibrose cística (FC). Nosso objetivo foi determinar os fatores de risco e identificar possíveis marcadores bioquímicos de doença óssea relacionada à FC (DOFC) em uma coorte única de pacientes com FC e doença pulmonar terminal submetidos a avaliação para transplante de pulmão (TxP). Métodos: Todos os pacientes com FC avaliados para TxP em nosso centro entre novembro de 1992 e dezembro de 2010 foram incluídos no estudo. Foram avaliados dados clínicos e marcadores bioquímicos de remodelação óssea, bem como a densidade mineral óssea (DMO) na coluna lombar e colo do fêmur. Foram usados rô de Spearman e análise de regressão logística multivariada. Resultados: Foram avaliados 102 pacientes adultos com FC. A média de idade foi de 28,1 anos (IC95%: 26,7-29,5), e a média do índice de massa corporal foi de 17,5 kg/m2 (IC95%: 17,2-18,2). A média do escore T foi de −2,3 e −1,9 na coluna lombar e colo do fêmur, respectivamente, sendo menor nos homens que nas mulheres (−2,7 vs. −2,0 na coluna lombar e −2,2 vs. −1,7 no colo do fêmur). No geral, 52% apresentaram escore T < −2,5 em um dos dois sítios esqueléticos. O genótipo homozigoto para Phe508del foi encontrado em 57% dos pacientes sem osteoporose e em 60% daqueles com DMO baixa. A média do escore T não foi particularmente baixa em pacientes com mutações graves do gene CFTR. Embora o IMC tenha se correlacionado com o escore T no colo do fêmur e coluna lombar, os níveis séricos de 25-hidroxivitamina D e paratormônio não o fizeram. Conclusões: A DOFC é comum em pacientes com FC e doença pulmonar terminal, particularmente em homens e pacientes com IMC baixo. O estado de mutação da FC aparentemente não se correlaciona com a DOFC. Além disso, aparentemente não há correlação entre DMO baixa e outros fatores de risco ou parâmetros bioquímicos. A prevalência de DOFC parece ter diminuído recentemente, o que provavelmente é reflexo do aumento dos esforços para antecipar o diagnóstico e tratamento.

Genetic and phenotypic traits of children and adolescents with cystic fibrosis in Southern Brazil / Características genéticas e fenotípicas de crianças e adolescentes com fibrose cística no Sul do Brasil

ABSTRACT Objectives: To characterize the main identified mutations on cystic fibrosis transmembrane conductance regulator (CFTR) in a group of children and adolescents at a cystic fibrosis center and its association with the clinical and laboratorial characteristics. Method: Descriptive cross-sectional study including patients with cystic fibrosis who had two alleles identified with CFTR mutation. Clinical, anthropometrical, laboratorial and pulmonary function (spirometry) data were collected from patients' records in charts and described with the results of the sample genotyping. Results: 42 patients with cystic fibrosis were included in the study. The most frequent mutation was F508del, covering 60 alleles (71.4%). The second most common mutation was G542X (six alleles, 7.1%), followed by N1303K and R1162X mutations (both with four alleles each). Three patients (7.14%) presented type III and IV mutations, and 22 patients (52.38%) presented homozygous mutation for F508del. Thirty three patients (78.6%) suffered of pancreatic insufficiency, 26.2% presented meconium ileus, and 16.7%, nutritional deficit. Of the patients in the study, 59.52% would be potential candidates for the use of CFTR-modulating drugs. Conclusions: The mutations of CFTR identified more frequently were F508del and G542X. These are type II and I mutations, respectively. Along with type III, they present a more severe cystic fibrosis phenotype. More than half of the sample (52.38%) presented homozygous mutation for F508del, that is, patients who could be treated with Lumacaftor/Ivacaftor. Approximately 7% of the patients (7.14%) presented type III and IV mutations, therefore becoming candidates for the treatment with Ivacaftor.

RESUMO Objetivos: Caracterizar as principais mutações identificadas no cystic fibrosis transmembrane conductance regulator (CFTR) em um grupo de crianças e adolescentes de um centro multidisciplinar de tratamento de fibrose cística e sua associação com características clínicas e laboratoriais. Método: Estudo transversal descritivo que incluiu pacientes com fibrose cística que possuíam dois alelos identificados com mutação no CFTR. Dados clínicos, antropométricos, laboratoriais e de função pulmonar (espirometria) foram coletados de registros em prontuários e descritos com os resultados de genotipagem da amostra. Resultados: Foram incluídos 42 pacientes com fibrose cística. A mutação mais frequente foi a F508del, abrangendo 60 alelos (71,4%). A segunda mutação mais comum foi a G542X (seis alelos, 7,1%), seguida das mutações N1303K e R1162X (ambas com quatro alelos cada uma). Três pacientes (7,14%) apresentaram mutações de classes III e IV, e 22 pacientes (52,38%), homozigose para F508del. Trinta e três pacientes (78,6%) tinham insuficiência pancreática, 11 (26,2%) apresentaram íleo meconial e sete (16,7%) déficit nutricional. Dos pacientes do estudo, 59,52% seriam potenciais candidatos ao uso de fármacos moduladores de CFTR. Conclusões: As mutações do CFTR identificadas com mais frequência foram F508del e G542X, as quais são mutações pertencentes às classes II e I, respectivamente, e que, juntamente à classe III, conferem um fenótipo de fibrose cística com mais gravidade. Mais da metade (52,38%) da amostra apresentava F508del em homozigose, população candidata ao novo tratamento com Lumacaftor/Ivacaftor. Aproximadamente 7% dos pacientes apresentavam mutações de classes III e IV, sendo candidatos ao tratamento com Ivacaftor.

Progresos en farmacoterapia en fibrosis quística / Advances in farmacotherapy for cystic fibrosis

Cystic fibrosis is an autosomal recessive multisystemic disease caused by a mutation in the gene encoding the CFTR protein (cystic fibrosis transmembrane conductance regulator). For decades treatments were focused on pulmonary and extrapulmonary symptoms, but in recent years new treatments based on genetics and CFTR mutations have been proposed. The first treatment to appear was genetic therapy, which did not show long-term benefits. These new treatments have allowed a more individualized scheme by using potentiators and modulators of CFTR. Phase III studies and systematic revisions have demonstrated pulmonary function improvement, lower rates of FEV1 decline, reduction in pulmonary exacerbations, BMI improvement and better chloride transport revealed by the sweat test. Recent literature has also shown that these effects persist in the long term.

La Fibrosis Quística es una enfermedad multisistémica autosómica recesiva causada por la mutación del gen que codifica al canal CFTR (proteína de regulación de transmembrana de Fibrosis Quística). Desde hace varias décadas se han utilizado tratamientos enfocados en síntomas pulmonares y extrapulmonares, pero los últimos años han surgido tratamientos basados en genética y mutaciones del CFTR. Inicialmente fue la terapia génica, la cual a largo plazo no demostró beneficios. Las nuevas terapias han permitido un tratamiento individualizado, mediante potenciadores y moduladores del CFTR, demostrándose en estudios fase III y revisiones sistemáticas mejoría en la función pulmonar, disminución de la velocidad de declinación del VEF1, reducción de exacerbaciones pulmonares, mejoría del IMC y del transporte de cloro medido en test del sudor, observándose efectos mantenidos a largo plazo.

Variants in the interleukin 8 gene and the response to inhaled bronchodilators in cystic fibrosis / Variantes no gene da interleucina 8 e a resposta a broncodilatadores inalatórios na fibrose cística

Abstract Objective: Interleukin 8 protein promotes inflammatory responses, even in airways. The presence of interleukin 8 gene variants causes altered inflammatory responses and possibly varied responses to inhaled bronchodilators. Thus, this study analyzed the interleukin 8 variants (rs4073, rs2227306, and rs2227307) and their association with the response to inhaled bronchodilators in cystic fibrosis patients. Methods: Analysis of interleukin 8 gene variants was performed by restriction fragment length polymorphism of polymerase chain reaction. The association between spirometry markers and the response to inhaled bronchodilators was evaluated by Mann-Whitney and Kruskal-Wallis tests. The analysis included all cystic fibrosis patients, and subsequently patients with two mutations in the cystic fibrosis transmembrane conductance regulator gene belonging to classes I to III. Results: This study included 186 cystic fibrosis patients. There was no association of the rs2227307 variant with the response to inhaled bronchodilators. The rs2227306 variant was associated with FEF50% in the dominant group and in the group with two identified mutations in the cystic fibrosis transmembrane conductance regulator gene. The rs4073 variant was associated with spirometry markers in four genetic models: co-dominant (FEF25-75% and FEF75%), dominant (FEV1, FEF50%, FEF75%, and FEF25-75%), recessive (FEF75% and FEF25-75%), and over-dominant (FEV1/FVC). Conclusions: This study highlighted the importance of the rs4073 variant of the interleukin 8 gene, regarding response to inhaled bronchodilators, and of the assessment of mutations in the cystic fibrosis transmembrane conductance regulator gene.

Resumo Objetivo: A proteína interleucina 8 promove respostas inflamatórias, o que inclui sua atuação nas vias aéreas. A presença de variantes no gene da interleucina 8 causa respostas inflamatórias alteradas e possivelmente respostas variadas ao uso de broncodilatadores inalatórios. Assim, este estudo analisou as variantes da interleucina 8 (rs4073, rs2227306, rs2227307) e sua associação à resposta a broncodilatadores inalatórios em pacientes com fibrose cística. Métodos: Foi feita análise das variantes genéticas da interleucina 8 por restriction fragment length polymorphism da reação em cadeia da polimerase. A associação entre os marcadores da espirometria e a resposta a broncodilatadores inalatórios foi feita pelos testes de Mann-Whitney e Kruskal-Wallis. A análise incluiu todos os pacientes com fibrose cística e posteriormente pacientes com duas mutações no gene cystic fibrosis transmembrane conductance regulator pertencentes às Classes I a II. Resultados: Este estudo incluiu 186 pacientes com fibrose cística. Não houve associação da variante rs2227307 à resposta a broncodilatadores inalatórios. A variante rs2227306 foi associada a FEF50% no grupo dominante e no grupo com duas mutações identificadas no gene cystic fibrosis transmembrane conductance regulator. A variante rs4073 foi associada a marcadores da espirometria em quatro modelos genéticos: codominante (FEF25-75% e FEF75%), dominante (VEF1, FEF50%, FEF75% e FEF25-75%), recessivo (FEF75% e FEF25-75%) e overdominante (VEF1/CVF). Conclusões: Este estudo destaca, principalmente, a importância da variante rs4073 do gene da interleucina 8, na resposta a broncodilatadores inalatórios, concomitantemente ao genótipo das mutações no gene cystic fibrosis transmembrane conductance regulator.

Diagnóstico genético de la fibrosis quística: una experiencia provincial de 10 años, Mendoza, Argentina / Genetic diagnosis of cystic fibrosis: a 10-year provincial experience, Mendoza, Argentina

OBJETIVOS: El presente trabajo tiene por objetivo presentar el perfil genético de enfermos fibroquísticos de la Provincia de Mendoza. Pacientes y método: Se estudiaron 105 pacientes derivados del Centro de Fibrosis Quística con diagnóstico clínico o test del sudor positivo. TÉCNICA: INNO-LIPA-CFTR 19 e INNOLIPACFTR17; amplificación genómica mediante PCR multiplex con sondas alelo-específicas. RESULTADOS: Se encontraron 18 mutaciones diferentes causantes de fibrosis quística. El 33,3% corresponde a la F508del; N1303K = 8,5%; G542X = 6,2%; W122X = 3,3%. Se detectó la mutación “africana” 3.120 + 1G > A en el 2,8% de los casos. CONCLUSIÓNES: nuestra prevalencia y espectro de mutaciones en fibrosis quística difieren de otras publicadas en el país. El hallazgo de mutaciones reportadas con mayor frecuencia en países africanos sugiere que nuestra población tiene influencias étnicas diferentes. Se discuten las imprecisiones diagnósticas que han generado en pequeños grupos de enfermos los nuevos avances de laboratorio en genética: enfermos “SMAF-Q Y PAF-Q” (explicación en el texto).

OBJECTIVE: To present the genetic background of Cystic Fibrosis Patients from the Province of Mendoza, Argentina. Patients and method: 105 patients were studied during 10 years. referred from a Cystic Fibrosis Center to the genetic laboratory. Cystic Fibrosis phenotype and /or abnormal sweat test were the referral reasons. TECHNIQUE: INNO-LIPA-CFTR19 and INNOLIPA CFTR 17, genome amplification through PCR multiplex with allele specific probes were used. RESULTS: 18 different mutations were detected F508 del frequency was 33.3%; N1303K: 8.5%; G542X: 6.2%; W122X: 3.3%. The “African” mutation 3120 + 1G > A was found in 2.8% of cases. CONCLUSIONS: Our prevalence of Cystic Fibrosis mutations differs markedly from others reported in our Country. African mutation detection suggests a different ethnic origin for our population. We discuss a small group of patients where genetic studies seem to have created diagnostic difficulties (metabolic syndrome and cystic fibrosis associated pathology).

Frecuencia de las mutaciones más comunes del gen CFTR en pacientes peruanos con fibrosis quística mediante la técnica ARMS-PCR / Frequency of the most common mutations of the CFTR gene in peruvian patients with cystic fibrosis using the ARMS-PCR technique

RESUMEN Objetivos. Determinar la frecuencia de las diez mutaciones más comúnmente reportadas en América Latina del gen CFTR mediante Sistema de Mutación Refractario a la amplificación por PCR (ARMS-PCR) en los pacientes con fibrosis quística (FQ) de dos instituciones hospitalarias de referencia en el Perú durante el año 2014. Materiales y métodos. Se evaluó la frecuencia de las diez comúnmente reportadas más comúnmente reportadas del gen CFTR en los pacientes del Hospital Nacional Edgardo Rebagliati Martins y el Instituto Nacional de Salud del Niño, ambos ubicados en Lima, Perú. Se recogieron muestras de sangre de 36 pacientes con FQ y se utilizó la técnica de ARMS-PCR para determinar la presencia de tales mutaciones. Resultados. Se incluyó al 73,5% de los pacientes con diagnóstico conocido de FQ en el país al momento en que se realizó el estudio. El diagnóstico por ARMS-PCR permitió identificar las mutaciones en 30,6% de los alelos de los pacientes con FQ, el 64,9% de los alelos mutados no fue identificado. Las mutaciones encontradas fueron p.Phe508del (22,2%), p.Gly542* (6,9%) y p.Arg1162* (1,4%). Conclusiones. Existe una variabilidad significativa de las mutaciones presentes en nuestra población de estudio en comparación con lo reportado en otros países de Latinoamérica, tanto en la frecuencia como en el tipo. Es necesario realizar estudios que usen la tecnología de secuenciación completa del gen CFTR para identificar otras mutaciones presentes en nuestra población.

ABSTRACT Objectives. To determine the frequency of the ten most common mutations of the CFTR gene reported in Latin Americausing amplification-refractory mutation system-polymerase chain reaction (ARMS-PCR) in patients with cystic fibrosis (CF) in two referral hospitals in Peru during the year 2014. Materials and Methods. The frequency of the ten most common mutations of the CFTR gene was assessed in patients of the Hospital Nacional Edgardo Rebagliati Martins and the Instituto Nacional de Salud del Niño, both located in Lima, Peru. Blood samples were collected from 36 patients with CF, and the ARMS-PCR technique was used to determine the presence of these mutations. Results. The study group included 73.5% of patients with a known diagnosis of CF in the country when the study was carried out. ARMS-PCR allowed three of the mutations to be identified in a combined 30.6% of the alleles from patients with CF, and 64.9% of the mutated alleles were not identified. The mutations found were p.Phe508del (22,2%), p.Gly542* (6,9%), and p.Arg1162* (1,4%). Conclusions. There is significant variability in both the frequency and type of mutations present in our study population and in what has been reported in other Latin American countries. It is necessary to perform studies that use complete sequencing technology for the CFTR gene to identify other mutations present in our population.

Diagnóstico molecular de fibrosis quística en venezuela / Molecular diagnosis of cystic fibrosis in venezuela

La fibrosis quística (FQ) es una enfermedad genética hereditaria, causada por mutaciones en el gen CFTR, por lo que se requiere una prueba molecular de ADN (ácido desoxirribonucleico) para la confirmación del diagnóstico clínico, que oriente el pronóstico del paciente y permita dirigir el tratamiento más acertado así como la correcta asesoría familiar. La intención del siguiente trabajo es proveer una herramienta sencilla y precisa que permita la comprensión de la importancia de un examen de diagnóstico molecular en pacientes confirmados clínicamente o sospechosos de poseer fibrosis quística y su interpretación por parte del personal médico o del paciente. También se describen los últimos avances en el diagnóstico molecular de la FQ en la población venezolana, se reportan las mutaciones más frecuentes, el panel de mutaciones sugerido para esta población y también se reseña el estatus del servicio para diagnóstico molecular de FQ más robusto establecido en el país(AU)

Cystic fibrosis (CF) is an inherited genetic disorder caused by mutations in the CFTR gene, which necessarily requires a molecular DNA test to confirm the clinical diagnosis, orient the patient's prognosis and to direct the most successful patient's treatment and proper family counseling. The objective of the following paper is to provide a simple and accurate tool that would allow the understanding of the importance of a molecular diagnostic test in patients with cystic fibrosis and their interpretation by the patient or medical personnel. Also we highlighted recent advances in the molecular diagnosis of CF in the Venezuelan population, reported the most frequent mutations, the mutations panel suggested and reported the status of the CF molecular diagnosis service more robust established the country(AU)

PRSS1, SPINK1, CFTR, and CTRC Pathogenic Variants in Korean Patients With Idiopathic Pancreatitis

BACKGROUND: This study aimed to identify pathogenic variants of PRSS1, SPINK1, CFTR, and CTRC genes in Korean patients with idiopathic pancreatitis. METHODS: The study population consisted of 116 Korean subjects (65 males, 51 females; mean age, 30.4 yr, range, 1-88 yr) diagnosed with idiopathic chronic pancreatitis (ICP), idiopathic recurrent acute pancreatitis (IRAP), or idiopathic acute pancreatitis (IAP). We analyzed sequences of targeted regions in the PRSS1, SPINK1, CFTR, and CTRC genes, copy numbers of PRSS1 and SPINK1, and clinical data from medical records. RESULTS: We identified three types of pathogenic PRSS1 variants in 11 patients, including p.N29I (n=1), p.R122H (n=1), and p.G208A (n=9). Sixteen patients exhibited heterozygous pathogenic variants of SPINK1, including c.194+2T>C (n=12), p.N34S (n=3), and a novel pathogenic splicing variation c.194+1G>A. A heterozygous CFTR p.Q1352H pathogenic variant was detected in eight patients. One patient carried a heterozygous CTRC p.P249L pathogenic variant, which is a known high-risk variant for pancreatitis. All patients had normal PRSS1 and SPINK1 gene copy numbers. Weight loss occurred more frequently in patients carrying the p.G208A pathogenic variant, while pancreatic duct stones occurred more frequently in patients with the c.194+2T>C pathogenic variant. CONCLUSIONS: Pathogenic variants of PRSS1, SPINK1, and CFTR were associated with idiopathic pancreatitis, while pathogenic variants of CTRC were not. Copy number variations of PRSS1 and SPINK1 were not detected.

Fibrosis quística en el adulto / Cystic fibrosis in adults

La Fibrosis Quística (FQ) es una enfermedad hereditaria autosómica recesiva. La detección precoz sumado a medidas de intervención temprana han modificado el curso de esta enfermedad con mejorías en su sobrevida, lo que ha llevado a una población creciente de pacientes de 18 años. La mutación genética determina una alteración en una Proteína Reguladora de Conductancia Transmembrana (CFTR) que afecta a numerosos órganos y sistemas, pero el compromiso pulmonar es el que causa mayor morbimortalidad. El germen más frecuente que infecta a adultos es Pseudomonas aeruginosa y si bien hay una serie de medidas para el manejo de la infección crónica por Pseudomonas las terapia dirigida a la restauración de la función de la proteína CFTR hatomadorelevancia. Cuando la falla respiratoria progresa, la única alternativa disponible es el trasplante pulmonar que mejora la sobrevida y la calidad de vida en estos pacientes.

Cystic Fibrosis (CF) is an autosomal recessive hereditary disease. Early detection combined with early intervention measures have changed the course of this disease with improvements in their survival which has led to a growing population of patients 18 years. The genetic mutation determines an alteration in Transmembrane Conductance Regulator protein (CFTR) that affects many organ systems, but the pulmonary involvement is causing increased morbidity and mortality. The most common pathogen that infects adults is Pseudomonas aeruginosa and while there are a number of measures for the management of chronic Pseudomonas infection of therapy aimed at restoring the function of the CFTR protein has gained importance. When respiratory failure progresses only alternative available is lung transplantation improves survival and quality of life in these patients.

Secuenciación del gen CFTR en un grupo de pacientes chilenos con fibrosis quística / CFTR gene sequencing in a group of Chilean patients with cystic fibrosis

Introduction: Cystic fibrosis (CF) is an autosomal recessive genetic disorder caused by mutations of the CFTR gene, in which over 1,900 different mutations have been identified. In Chile, the diagnosis panel with the 36 most common mutations detects approximately 50% of all alleles, while for Caucasians, it is nearly 90%. The objective of this study is to expand the capacity of mutational screening in Chilean patients and look for recurrent mutations at the national level. Method: The detection of unknown pathogenic alleles was assessed by CFTR gene sequencing in a selected group of patients from the National Cystic Fibrosis Foundation (NCFF). 39 patients, who met the CF diagnostic criteria and had only one allele identified according to the mutational panel, were studied. Massive sequencing was performed throughout the investigation and the main CFTR databases were used for analysis. Results: The second pathogenic allele was identified in 16 of 39 patients of this study (41%), finding eleven different mutations that had not been reported in our population. We believe that the reason is that one of the variants had not been previously described. Conclusions: Mutations that had been described mainly in Hispanic and/or Mediterranean populations were identified. We found a variation that had not been previously reported, but not enough recurrent mutations that could explain the low rate of detection were found. Knowledge about mutations can provide appropriate genetic counseling and will be critical to evaluate the potential use of new targeted therapies for treating them.

Introducción: La fibrosis quística (FQ) es un trastorno autosómico recesivo causado por mutaciones en el gen CFTR, en el cual se han identificado más de 1.900 mutaciones diferentes. En Chile, el panel diagnóstico con las 36 mutaciones más comunes permite una tasa de detección cercana al 50% de los alelos, mientras que en caucásicos la tasa es casi de 90%. El objetivo fue ampliar la capacidad de detección mutacional en los pacientes chilenos y buscar mutaciones que pudieran ser recurrentes a nivel local. Pacientes y Método: Se evaluó la detección de alelos patogénicos desconocidos mediante la secuenciación del gen CFTR en un grupo seleccionado de pacientes del Programa Nacional de FQ (PNFQ). Se analizaron 39 pacientes, que cumplían los criterios diagnósticos de FQ y que tenían sólo un alelo identificado con el panel mutacional. Se realizó secuenciación masiva y para el análisis se utilizaron las principales bases de datos de CFTR. Resultados: En este grupo seleccionado de pacientes se identificó el segundo alelo patogénico en 16 de los 39 pacientes (41%), encontrándose once diferentes mutaciones que no se habían reportado en nuestra población. Según nuestro conocimiento, una de las variantes no había sido descrita previamente. Conclusiones: Se identificaron mutaciones que habían sido descritas principalmente en poblaciones hispánicas y/o mediterráneas. Encontramos una variante no reportada, aunque no encontramos mutaciones lo suficientemente recurrentes que pudieran explicar la baja tasa de detección. El conocimiento de las mutaciones permite otorgar un adecuado asesoramiento genético y será fundamental para evaluar el potencial uso de nuevas terapias específicas para las mutaciones.

Variabilidad fenotípica de la fibrosis quística: reporte de 2 gemelos con la mutación F508/F508 / Phenotypic variability of cystic fibrosis: case report of twins with F508/F508 mutation

Introduction: Cystic fibrosis (CF) is an autosomal recessive disease caused by a mutation in the CFTR gene, resulting in an alteration of a protein involved in sodium and chloride transport in the apical plasma membrane of epithelial cells in respiratory and intestinal tracts. It primarily presents respiratory compromise, affecting other systems in different ways. Meconium ileus is a gastrointestinal manifestation that occurs in 10-20% of patients, which is not entirely attributable to a specific CFTR mutation. Objective: To report a case of monozygotic twins diagnosed with CF (F508) in whom phenotypic variation is evident based on the expression of meconium ileus, showing that there are external modifiers in the development of this complication. Case report: monoamniotic monochorionic twin pregnancy which resulted in preterm births. One of the patient presented meconium ileus at birth leading to CF suspicion and establishing the diagnosis by (F508/F508) molecular analysis in both twins. Conclusion: Phenotypic variability in these twins supports the hypothesis proposed by different authors that there are other gene expression-modulation factors of the disease as well as environmental modifiers that must be taken into account when dealing with this disease.

Introducción: La fibrosis quística (FQ) es una enfermedad autosómica recesiva debida a una mutación en el gen CFTR, resultando en una alteración de una proteína implicada en el transporte de sodio y cloro en la membrana apical de células del epitelio respiratorio y gastrointestinal; presenta principalmente compromiso respiratorio, afectando otros sistemas de manera variable. El íleo meconial es una manifestación gastrointestinal presente en 10-20% de los pacientes, no del todo atribuible una mutación específica del CFTR. Objetivo: Reportar un caso de dos gemelos monocigóticos con diagnóstico de FQ (ΔF508), en quienes es evidente la variabilidad fenotípica en cuanto a la expresión de íleo meconial, poniendo de manifiesto que existen modificadores externos a la mutación en el desarrollo de esta complicación. Reporte de caso: Gemelos producto de embarazo monocorial monoamniotico, nacidos pretérmino, uno de ellos presenta íleo meconial al nacimiento lo que lleva al estudio de FQ, estableciendo el diagnóstico por análisis molecular (ΔF508/ΔF508) en ambos gemelos. Conclusión: La variabilidad fenotípica en estos gemelos apoya la hipótesis planteada por diferentes autores de que existen otras factores genéticos moduladores de la expresión de la enfermedad, así como modificadores ambientales, que deben ser tenidos en cuenta a la hora de abordar esta enfermedad.