Evolution of bone disease after renal transplantation: correlation between biochemical parameters and histopathological findings

Um transplante renal bem sucedido pode corrigir a maioria das anormalidades metabolicas que causam a osteodistrofia renal. Porem, crescentes evidencias mostram que a doenca ossea pode constituir um importante problema clinico apos o transplante renal. Neste estudo, avaliou-se, prospectivamente, a evolucao da doenca ossea atraves da analise da histomorfometria ossea e de parametros laboratoriais de pacientes antes e apos seis meses de um transplante renal bem sucedido. Ao todo, 25 pacientes (18M/7F), com idade mediana de 37 anos (20-58), foram incluidos no estudo. Vinte e tres estavam em hemodialise e 2, em CAPD; a duracao mediana em dialise foi de 23 meses (9-88). Analise histomorfometrica das biopsias osseas foi obtida em 20 pacientes. No pre-Tx, doze apresentavam doenca adinamica, 3, lesao minima, 3, doenca mista e 2, osteite fibrosa. No pos-Tx, onze apresentavam doenca adinamica, 8, lesao minima e 1, osteomalacia. Apesar de termos encontrado uma frequencia de doenca ossea adinamica comparavel no pre e no pos-Tx, os pacientes acometidos nas 2 fases do estudo nao eram exatamente os mesmos. Dos 12 casos de doenca adinamica no pre-Tx, 5 melhoraram a formacao e mineralizacao ossea passando a lesao minima, e sete, permaneceram como doenca ossea adinamica. Os pacientes com lesoes relacionadas ao hiperparatireoidismo evoluiram com melhora ou resolucao completa dessas alteracoes. Entretanto, cinco evoluiram com doencas de baixo turnover osseo (4 com doenca adinamica e 1 com osteomalacia). Tres dos 4 pacientes que evoluiram como adinamicos apresentavam persistencia dos depositos de aluminio e/ou ferro em suas superficies osseas. 0 outro e aquele com osteomalacia apresentavam hipofosfatemia e PTHi elevado. Os parametros laboratoriais tambem tiveram uma tendencia a normalizacao. Os dois unicos pacientes hipercalcemicos no pos-Tx apresentavam doenca ossea de baixo turnover. Apos o Tx, o nivel do magnesio caiu e o do cloro, aumentou. Os pacientes com valores normais de fosfatase alcalina ossea no pre-Tx evoluiram com aumento significante deste parametro. Nao houve correlacao entre fosfatase alcalina ossea e PTHi no pos-Tx. O PTHi reduziu-se significantemente naqueles com valores iniciais aumentados, poreem, 4 persistiram com PTHi acima do normal. No pos-Tx, nao houve correlacao da fosfatase alcalina ossea ou do PTHi com qualquer dos parametros histomorfometricosa(au)BV UNIFESP: Teses e dissertaçõe

Effects of in-center daily hemodialysis upon mineral metabolism and bone disease in end-stage renal disease patients

CONTEXT: Alternative hemodialysis schedules have been proposed to improve the quality of the dialysis. Nonetheless, their influence upon mineral and bone disorders is unknown. OBJECTIVE: To report the impact of a daily hemodialysis schedule upon the lesions of renal osteodystrophy. TYPE OF STUDY: Prospective non-controlled study. SETTING: Public University Hospital. PARTICIPANTS: Five patients treated by daily hemodialysis for at least 24 months. INTERVENTION: Daily dialysis sessions were accomplished with non-proportional dialysis machines without an ultrafiltration control device, with blood flow of 300 ml/min, bicarbonate dialysate ([Ca]=3.5 mEq/L) at 500 ml/min, and low-flux membrane dialyzers. Sessions were started at 6:00 p.m. (except Sundays) and lasted 2 hours. MAIN MEASUREMENTS: Serum levels of Ca and P from the last 6 months on conventional hemodialysis for the same patients were used for comparison with each semester of daily hemodialysis. Bone biopsies and PTH levels were obtained at the end of the conventional hemodialysis period and then again after 2 years of daily hemodialysis. RESULTS: Mean serum calcium was significantly higher during the second and third semesters of daily dialysis [10.0 mg% (SD 0.6), and 10.0 mg% (SD 0.8), respectively] compared to standard dialysis [9.4 mg% (SD 0.8)], p < 0.05. Mean values for phosphorus were significantly lower during every semester of daily hemodialysis [6.3 mg% (SD 1.8), 5.8 mg% (SD 1.7), 6.0 mg% (SD 1.7), and 6.0 mg% (SD 1.8)] compared to standard dialysis [7.2 mg% (SD 2.7)], P < 0.05. Variations in mean Ca x P product followed the same pattern as for phosphorus [59.5 (SD 16.0), 57.1 (SD 16.3), 59.8 (SD 17.7), and 58.31 (SD 20.9) vs. 68.6 (SD 27.3), P < 0.05]. After 2 years on daily hemodialysis, 2 patients who had aplastic lesion were found to have mild bone disorder. In addition, one patient with mixed bone lesion and moderate bone aluminum accumulation had osteitis fibrosa with no aluminum. Intact PTH values at the beginning of study and after 2 years on daily hemodialysis did not differ [134 pg/ml (SD 66) vs. 109 pg/ml (SD 26), P = 0.60, respectively]. CONCLUSIONS: Patients treated using daily hemodialysis had better control of serum phosphorus and perhaps a lower risk of metastatic calcifications. Daily hemodialysis also seemed to be beneficial to low turnover bone disease and bone aluminum deposition

Calcium acetate versus calcium carbonate in the control of hyperphosphatemia in hemodialysis patients

CONTEXT: Hyperphosphatemia has an important role in the development of bone and mineral abnormalities in end-stage renal disease (ESRD). OBJECTIVE: To compare the phosphorus binding power and the hypercalcemic effect of calcium acetate and calcium carbonate in hemodialysis patients. TYPE OF STUDY: Crossover, randomized, double-blind study. PLACE: A private hospital dialysis center. PARTICIPANTS: Fifty-two patients who were undergoing regular hemodialysis three times a week ([Ca++] dialysate = 3.5 mEq/L). PROCEDURES: Half of the patients were started on 5.6 g/day of calcium acetate and, after a 2 week washout period, received 6.2 g/day of calcium carbonate. The other half followed an inverse protocol. MAIN MEASUREMENTS: Clinical interviews were conducted 3 times a week to monitor for side effects. Determinations of serum urea, calcium, phosphorus, hematocrit, Kt/V and blood gas analysis were obtained before and after each treatment. RESULTS: Twenty-three patients completed the study. A significant increase in calcium plasma levels was only observed after treatment with calcium carbonate [9.34 mg/dl (SD 0.91) vs. 9.91 mg/dl (SD 0.79), P < 0.01]. The drop in phosphorus levels was substantial and significant for both salts [5.64 mg/dl (SD 1.54) vs. 4.60 mg/dl (SD 1.32), P < 0.01 and 5.89 mg/dl (SD 1.71) vs. 4.56 mg/dl (SD 1.57), P < 0.01, for calcium acetate and calcium carbonate respectively]. The percentage reduction in serum phosphorus (at the end of the study) per milliequivalent of salt administered per day tended to be higher with calcium acetate but statistical significance was not found. CONCLUSION: Calcium acetate can be a good alternative to calcium carbonate in the handling of hyperphosphatemia in ESRD patients. When calcium acetate is used, control of hyperphosphatemia can be achieved with a lower administration of calcium, perhaps with a lower risk of hypercalcemia

The renal osteodystrophy pattern in Brazil and Uruguay: An overview

Background. The prevalence of the types of renal osteodystrophy (ROD) has changed in the last two decades. This study evaluates the prevalence and determining factors of the types of ROD in two countries in South America.Methods. Symptomatic patients who underwent bone biopsies for diagnostic purposes (1985 through 2001) were included in the study. In Brazil, a total of 2340 patients were reviewed, 93.1% on hemodialysis (HD), and 6.9% on continuous ambulatory peritoneal dialysis (CAPD). In Uruguay, 167 patients on hemodialysis were included. Uncalcified bone samples were analyzed in order to diagnose the different types of ROD.Results. Comparing. the 1980s to the 1990s, the prevalence of Brazilian patients with hyperparathyroid bone disease (HP) increased from 32.3% to 44.0%, while Al overload decreased from 61.3% to 42.4%. A logistic regression analysis showed that the main factors associated with HP included female gender, age of less than 40 years, black patients, longer time on dialysis, and absence of Al overload. In Uruguay, HP also increased over time from 31.8% to 70.5% (P < 0.05), while Al overload decreased from 42% to 27% (P < 0.05).Conclusion. A better control of Al overload may lead to a change in histologic pattern, as evidenced by the increasing prevalence of HP.Univ Fed Ceara, Fortaleza, Ceara, BrazilHosp Clin Montevideo, Montevideo, UruguayUniv Fed Sao Paulo, Sao Paulo, BrazilUniv Fed Fluminense, BR-24220000 Niteroi, RJ, BrazilUniv Fed Sao Paulo, Sao Paulo, BrazilWeb of Scienc

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data