Controversias sobre el rastreo de los niveles séricos de vitamina D y su suplementación / Controversies about serum vitamin D levels screening and its supplementation

Si bien los niveles bajos de vitamina D se han asociado con varios resultados de interés en salud, aún resulta motivo de controversia qué significa un nivel bajo, cual es la utilidad de su suplementación y cuales son sus potenciales efectos adversos. En ese contexto, se realizó en el Servicio de Medicina Familiar y Comunitaria del Hospital Italiano un taller de discusión denominado "Actividad ECCO" (Evidencia Científica en la Clínica Cotidiana) en la que fueron presentados los resulta-dos de estudios identificados que hubieran comparado el uso de vitamina D (con o sin suplementación de calcio) ver-sus placebo, con el objetivo de discutir cuál es la evidencia actual para el rastreo de deficiencia de vitamina D y para, eventualmente, recomendar o no su suplementación. Este artículo resume la evidencia identificada y las conclusiones consensuadas en dicha actividad. (AU)

Although low levels of vitamin D have been associated with several health outcomes, it is controversial what a low level means, the usefulness of its supplementation and its potential adverse effects. In this context, a workshop called "ECCO Activity" (Scientific Evidence in the Daily Clinic) was held in the Family and Community Medicine Division of Hospital Italiano de Buenos Aires, where the results of identified studies that compared the use of vitamin D (with or without calcium supplementation) versus placebo, with the aim of discussing what is the current evidence for screening of vitamin D deficiency and to, eventually, recommend or not its supplementation. This article summarizes the identified evidence and the agreed conclusions in that activity. (AU)

Prevalence of low bone mineral density in adolescents and adults with cystic fibrosis / Prevalência de densidade mineral óssea baixa em adolescentes e adultos com fibrose cística

Objective The aim of this cross-sectional study was to evaluate the prevalence of low bone mass density in cystic fibrosis patients as well as to evaluate the factors associated with bone mass in such patients. Methods Bone mass density was measured by dual-photon X-ray absorptiometry of lumbar spine (L1-L4), in patients ≤19 years old, or lumbar spine and femur (total and neck) in patients ≥20 years old. Evaluations of nutritional status, biochemical parameters, and lung function were performed. Medication data were obtained from medical records. Results Fifty-eight patients were included in the study (25 males/ 33 females), mean age 23.9 years (16-53years). The prevalence of bone mass below the expected range for age at any site was 20.7%. None of the subjects had history of fracture. Lumbar spine Z-score in cystic fibrosis patients correlated positively with body mass index (r= 0.3, p=0.001), and forced expiratory volume in the first second (% predicted) (r=0.415, p=0.022). Mean lumbar spine Z-score was higher in women (p=0.001), in patients with no pancreatic insufficiency (p=0.032), and in patients with no hospitalization in the last 3 months (p=0.02). After multivariate analysis, body mass index (p= 0.001) and sex (p=0.001) were independently associated with Z-score in lumbar spine. Conclusion Low bone mass is a frequent problem in patients with CF, being independently associated with body mass index, and male sex. .

Objetivo Determinar a prevalência de massa óssea baixa em pacientes adolescentes e adultos com fibrose cística e estudar os fatores potencialmente associados. Métodos Densidade mineral óssea foi determinada por absorciometria por dupla emissão de raios X na coluna lombar em pacientes ≤ 19 anos e na coluna e no fêmur em pacientes ≥ 20 anos. Avaliações nutricionais, bioquímicas e pulmonares foram realizadas. Dados referentes ao tratamento farmacológico foram coletados. Resultados 58 pacientes foram incluídos no estudo (25 homens/33 mulheres), média de idade de 23,9 anos (16-53). Massa óssea abaixo da esperada foi verificada em 20,7% dos pacientes. Não houve histórico de fratura. Z-score da coluna lombar associou-se positivamente com índice de massa corporal (r=0,3; p=0,022), volume expiratório forçado (% previsto) (r=0,415; p=0,001). A média do Z-score da coluna foi mais alta nas mulheres que nos homens (p=0,001), em pacientes que não possuíam insuficiência pancreática (p=0,02) e em pacientes que não haviam sido hospitalizados nos últimos três meses (p=0,032). Os fatores encontrados como preditores independentes de Z-score da coluna lombar foram sexo masculino (p=0,001) e índice de massa corporal (p=0,001). Conclusão Massa óssea baixa é frequente em pacientes com FC, estando associada independentemente com índice de massa corporal e sexo masculino. .

Novel CFTR Mutations in a Korean Infant with Cystic Fibrosis and Pancreatic Insufficiency

Cystic fibrosis (CF) is an autosomal recessive disease that is very rare in Asians: only a few cases have been reported in Korea. We treated a female infant with CF who had steatorrhea and failure to thrive. Her sweat chloride concentration was 102.0 mM/L. Genetic analysis identified two novel mutations including a splice site mutation (c.1766+2T>C) and a frameshift mutation (c.3908dupA; Asn1303LysfsX6). Pancreatic enzyme replacement and fat-soluble vitamin supplementation enabled the patient to get a catch-up growth. This is the first report of a Korean patient with CF demonstrating pancreatic insufficiency. CF should therefore be considered in the differential diagnosis of infants with steatorrhea and failure to thrive.

Correlación genotipo fenotipo de un grupo de pacientes con fibrosis quística / Correlation between phenotype and genotype in a group of patients with cystic fibrosis

Background: Cystic fibrosis (CF) is the most common lethal autosomic disease in Caucasians, with a global incidence of 1:3000 newborns. More than 900 mutations have been described, involving the Cystic Fibrosis Transmembrane Regulator (CFTR). The ÆF508 mutation is present in 60 percent of alleles studied worldwide. Aim: To report 25 patients with cystic fibrosis in whom a genetic study was done. Material and methods: Twenty five patients (14 men, aged between 18 months and 25 years) with a diagnosis of cystic fibrosis based on clinical features plus two abnormal sweat tests are reported. The genetic study considered the 20 most common mutations in cystic fibrosis and was done in genomic DNA of peripheral lymphocytes, by polymerase chain reaction. Results: A mutation was found in 75 percent of analyzed alleles. ÆF508 was present in 50 percent of cases (ÆF508/ÆF508 in 8 and ÆF508/other in 11). When ÆF508 was present, pancreatic insufficiency was always a feature and nutritional status was worse. Respiratory involvement was variable, both for homozygous and heterozygous cases. Other severe mutations such as W1282X and G542X were related to clinical manifestations similar to those found in ÆF508 mutation. Diagnosis was made before six months of age in 12 patients. The clinical presentation was meconium ileus and there was a family history of the disease in most cases. The majority of cases of early diagnosis presented severe mutations, but milder respiratory symptoms and lesser nutritional compromise at the time of assessment. Conclusions: Most patients studied had a severe cystic fibrosis mutation, which was associated with more severe respiratory, pancreatic and nutritional involvement. The early diagnosis of the disease, which would allow to improve the prognosis and the quality of life, must be emphasized

Allogeneic Bone Marrow Transplantation in Shwachman-Diamond Syndrome with Malignant Myeloid Transformation: A Case Report

Shwachman-Diamond syndrome (SDS) is a rare genetic disorder of unknown pathogenesis involving exocrine pancreatic insufficiency and hematological and skeletal abnormalities. About 25% of patients develop hematopoietic malignancies. We report on a case of acute myeloid leukemia (M2) in a 21-year-old woman affected by SDS. She was treated with conventional chemotherapy (idarubicin plus cytarabine) and reached complete remission of leukemia. After induction chemotherapy, she underwent allogeneic bone marrow transplantation (BMT). The BMT preparative regimen consisted of total body irradation (TBI) followed by cyclophosphamide. Cyclosporin A and short term methotrexate were used for graft-versus-host disease prophylaxis. After a follow-up of 12 months, she is alive leukemia free off any immunosuppressive agent. Although experience in this field is scarce, we speculate that bone marrow failure in SDS is an indication for BMT which is the only curative trentment option.

Shwachman-Diamond syndrome: the clinical imitador of cystic fibrosis

In this case we report the autopsy findings of a four-month-old boy with the diagnosis of Shwachman-Diamond syndrome. The clinical and pathologic findings are discussed with emphasis on the differential diagnosis of cystic fibrosis and a brief review of current literature

El laboratorio clínico en el estudio de las pancreatitis / Clinical laboratory in acute and chronic pancreatitis

Se revisan los exámenes de laboratorio útiles en el estudio de las pancreatitis. Se hace una breve descripción de los procedimientos, su sensibiliad y especificidad, así como disponibilidad e indicaciones. En la prancreatitis aguda se describen las diferentes determinaciones enzimáticas en suero y orina que se usan para establecer el diagnóstico y el pronóstico de la enfermedad; además se informan los resultados del análisis de otras sustancias como algunos reactantes de fase aguda que en forma aislada pueden ser útiles para conocer la gravedad de un episodio inflamatorio. En la pancreatitis crónica se señalan los diferentes estadios en pruebas que en cada uno de ellos pueden realizarse, con diferente grado de complejidad y que tienen un sensibilidad y especificidad menor, conforme es menos directa la estimulación o análisis de la función del páncreas. Sin embargo, se señalan métodos de exploración funcional que constituyen una alternativa útil, como son las pruebas comerciales de pancreolauril y PABA, o los más recientemente propuestos de aminoácidos plasmáticos y triglicéridos marcadores con C. El laboratorio clínico en el abordaje diagnóstico de las pancreatitis es complementario a los métodos de imagen y se considera indispensable que se realicen, al menos dos métodos precisos de determinación enzimática en suero y una prueba indirecta u otra no invasora que se valide para cada población y que permita el estudio de enfermos gastroenterológicos.