Hugo Abensur

Obstetric Outcome in Pregnant Women on Long-term Dialysis: A Case Series

BACKGROUND Although still uncommon, pregnancy frequency in women on maintenance hemodialysis therapy has increased in the past 20 years. Most published reports suggest that intensified hemodialysis regimens result in better pregnancy outcomes. The small number of patients investigated in all reported series is the main limitation of the available studies. STUDY DESIGN Retrospective case series. SETTING & PARTICIPANTS Data for all pregnancies that occurred in 1988-2008 in women undergoing maintenance hemodialysis (52 pregnancies) at the São Paulo University Medical School (São Paulo, Brazil). OUTCOMES & MEASUREMENTS We analyzed maternal and fetal outcomes of 52 pregnancies, as well as their relationship with various clinical, laboratory, and hemodialysis parameters, such as pre-eclampsia, pregnancy before or after dialysis therapy, hemodialysis dose, polyhydramnios, anemia, and predialysis serum urea level. In addition, logistic regression models for a composite adverse fetal outcome (perinatal death or extremely premature delivery) and linear regression models for birth weight were built. RESULTS 87% overall rate of successful delivery, with a mean gestational age of 32.7 +/- 3.1 weeks. Pre-eclampsia was associated with a poor prognosis compared with pregnancies without pre-eclampsia: a successful delivery rate of 60% versus 92.9% (P = 0.02), extremely premature delivery rate of 77.8% versus 3.3% (P < 0.001), lower gestational age (P < 0.001), and birth weight (P < 0.001). Patients with an adverse composite fetal outcome had a higher frequency of pre-eclampsia (P < 0.001), lower frequency of polyhydramnios (P = 0.03), lower third-trimester hematocrit (P = 0.03), and higher predialysis serum urea level (P = 0.03). The same results were seen for birth weight. LIMITATIONS Retrospective data analysis. The absence of creatinine clearance measurements did not allow evaluation of the impact of residual renal function on fetal outcome. CONCLUSIONS Outcomes of pregnancy in women undergoing hemodialysis often are good. Pre-eclampsia, third-trimester hematocrit, polyhydramnios, and predialysis serum urea level are important variables associated with fetal outcome and birth weight.

Intraperitoneal pressure and hernias in children on peritoneal dialysis

Abstract Abdominal wall hernias have been increasingly recognized in patients on continuous ambulatory peritoneal dialysis (CAPD). They are also more frequent in children than in adults. The aim of this study was to determine the influence of intraperitoneal pressure (IPP) on the development of hernias in children on CAPD, and if there was a difference between IPP in children and adults. We studied 14 children aged 11.2±3.2 years, body weight 31.1±9.4 kg, who had undergone CAPD for 16.2±14.4 months. Also, 10 adults were studied, aged 48±18 years, body weight 62.4±13.9 kg, on the CAPD program for 35±27 months. The IPP was measured via a column of dialysate in the peritoneal dialysis line, immediately before the drainage of the peritoneal cavity. The pressure was measured with the patients in the supine position, at the level of the umbilical cicatrix with the zero point located on the mean axillary line. IPP was measured at inspiration and at expiration, and the mean of these two measurements was calculated. The children were divided in two groups : group 1 (n=7) without hernias and group 2 (n=7) with hernias (5 umbilical and 2 inguinal). The IPP of all children was 9.5±2.9 cm H2O. The IPP was 8.1±2.6 and 10.9±2.6 cm H2O in groups 1 and 2, respectively (P=0.003). The instilled volume for test was similar in both groups. The IPP of the adults was 13.8±2.8 cm H2O, which was significantly greater than that of the children (P=0.001). In conclusion, hernia is a common complication in children on CAPD and its prevalence is affected by IPP. Other associated factors may be the presence of anatomically weak sites in the abdominal wall of the children, since IPP is lower in children than in adults.

Effects of bone remodelling on calcium mass transfer during haemodialysis

BACKGROUND During haemodialysis, calcium balance can affect, or be affected by, mineral metabolism. However, when dialysate calcium concentration (d[Ca]) is chosen or kinetic models are employed to calculate calcium balance, bone remodelling is rarely considered. In this study, we examined whether bone remodelling affects calcium mass transfer during haemodialysis. METHODS We dialysed 23 patients using a d[Ca] of 1.0, 1.25, 1.5 or 1.75 mmol/L. Calcium mass transfer was measured and associated with remodelling bone factors. RESULTS Calcium balance varied widely depending on the d[Ca]. Calcium removal was -578 +/- 389, -468 +/- 563, +46 +/- 400 and +405 +/- 413 mg when a d[Ca] of 1.0, 1.25, 1.5 or 1.75 mmol/L was used, respectively (1.0 and 1.25 vs 1.5 and 1.75 mmol/L, P < 0.001; 1.5 vs 1.75 mmol/L, P < 0.05). Univariate analysis showed that calcium balance correlated with calcium gradient, parathyroid hormone (PTH), osteocalcin and dialysis vintage. Multivariate analysis revealed that calcium balance was dependent on calcium gradient, PTH and osteocalcin. CONCLUSIONS These results suggest that bone remodelling could affect calcium mass transfer during haemodialysis.

Pruritus in hemodialysis patients: The problem remains

Pruritus is still one of the most common and disturbing symptoms of end‐stage renal disease. The objective of this study is to analyze the prevalence of pruritus in hemodialysis patients and the possible factors implicated in its genesis. In a cross‐sectional study, 101 patients on hemodialysis at our center were screened for pruritus. The relationship of various factors with pruritus was evaluated. Of the 101 patients included, 31(30.7%) had pruritus at the time of examination. Patients with pruritus were significantly older than those without pruritus (P=0.0027). Pruritus tended to be more prevalent in patients undergoing dialysis 3 times a week than in those undergoing daily dialysis, but the difference did not reach statistical significance (P=0.0854). Lower transferrin saturation levels were found in patients with pruritus than in those without pruritus (P=0.0144). C‐reactive protein levels were significantly higher in patients with pruritus than in those without pruritus (P=0.0013). There was no significant difference between the groups in the levels of the other inflammatory biomarkers measured. However, there was a tendency toward a correlation between the levels of α‐1‐glycoprotein and the intensity of pruritus (P=0.0834). Our results suggest a possible relationship of the inflammatory response upregulation to pruritus. Additionally, there was a positive relationship between pruritus and iron deficiency, possibly associated with inflammatory elevation of hepcidin. A better understanding of the factors implicated in the genesis of pruritus related to end‐stage renal disease is crucial in the development of more effective treatments for this symptom.

Guidelines to diagnosis and monitoring of Fabry disease and review of treatment experiences.

Ana Maria Martins, MD, PhD, Vânia D’Almeida, MD, Sandra Obikawa Kyosen, MD, Edna Tiemi Takata, MD, Alvimar Goncalves Delgado, MD, PhD, Ângela Maria Barbosa Ferreira Goncalves, MD, Caio Cesar Benetti Filho, MD, Dino Martini Filho, MD, Gilson Biagini, MD, Helena Pimentel, MD, Hugo Abensur, MD, PhD, Humberto Cenci Guimaraes, MD, Jaelson Guilhem Gomes, MD, Jose Sobral Neto, MD, PhD, Luiz Octavio Dias D’Almeida, PhD, Luiz Roberto Carvalho, MD, Maria Beatriz Harouche, MD, Maria Cristina Jacometti Maldonado, MD, Osvaldo J. M. Nascimento, PhD, Paulo Sergio dos Santos Montoril, MD, and Ricardo Villela Bastos, MD

Positive Acute-Phase Inflammatory Markers in Different Stages of Chronic Kidney Disease

Background: An elevated serum level of acute-phase inflammatory markers is associated with an increased risk of cardiovascular disease. We hypothesized that elevated acute-phase inflammatory markers are directly associated with the different stages of chronic kidney disease (CKD). Methods: We evaluated the relationship between serum levels of high-sensitivity C-reactive protein (hsCRP) and α1-acid glycoprotein (α1-AGP), as well as the renal function in 224 adult patients with CKD (mean age 56.6 years, 46% male, and 40% diabetics), stratified according to the glomerular filtration rate (GFR) (based on the National Kidney Foundation/Kidney Dialysis Outcomes Quality Initiatives), and in 94 hemodialysis patients. Results: The mean hsCRP was 8.2 ± 12.1 mg/l, and hsCRP levels were >5 mg/l in 44.4% of the patients; α1-AGP levels were >125 mg/dl in 33.3% of the patients. Mean hsCRP and α1-AGP were significantly higher in more severe stages of CKD. A weak inverse relationship was found between GFR and serum hsCRP (r = –0.2205; p = 0.0006) and between GFR and serum α1-AGP (r = –0.3266; p < 0.0001). There was a correlation between hsCRP and α1-AGP (r = 0.3417; p < 0.0001). No significant differences were detected between patients with CKD and those undergoing hemodialysis concerning hsCRP (8.2 ± 12.1 vs. 6.8 ± 7.4 mg/l; p = 0.2980) and α1-AGP (116.3 ± 42.5 vs. 117.2 ± 37.9 mg/dl; p = 0.8590). However, the level of hsCRP was significantly reduced in hemodialysis patients compared with patients with stage 5 predialytic disease (12.1 ± 13.9 to 6.8 ± 7.4 mg/l; p = 0.005). More patients with stage 5 predialytic CKD had an elevated hsCRP serum level compared with patients on hemodialysis (64.7 vs. 37.9%; χ2 = 6.230, p < 0.01). Conclusions: Approximately 50% of patients with CKD – even in the early phase of renal failure – exhibit an activated acute-phase response, which is closely related to the stages of CKD. Hemodialysis may partially correct the inflammatory process present in the immediate predialysis phase of CKD.

Anaphylactic reaction induced by a polysulfone/polyvinylpyrrolidone membrane in the 10th session of hemodialysis with the same dialyzer

The majority of severe hypersensitivity reactions in hemodialysis patients have occurred due to sensitization to ethylene oxide or to nonbiocompatible membrane dialyzers. The use of polysulfone dialyzers rarely causes hypersensitivity reactions. In the present study, we describe a case of severe life‐threatening reactions induced by polysulfone dialyzers (from different manufacturers subjected to a variety of sterilization methods), which occurred after 9 sessions of hemodialysis with the same prescription, exemplifying the complexity of such reactions.

Obstructive sleep apnea in patients on conventional and short daily hemodialysis.

Obstructive sleep apnea (OSA) is common among patients on maintenance hemodialysis. However, the factors associated with the origin of OSA as well as the cardiovascular consequences in this population are not completely understood. We evaluated, by standard overnight polysomnography, 24-hour ambulatory blood pressure (BP) monitoring and echocardiography in 30 patients (14 males, age 34 ± 11 years, BMI 23.2 ± 5.2) – 15 on short daily hemodialysis (SDH) and 15 matched patients on conventional hemodialysis (CHD). The hemodialysis dose (standard Kt/V) was higher in patients on SDH than on CHD (p = 0.001). OSA (apnea-hypopnea index >5 events/h) was present in 13 patients (43%). Patients with OSA were predominantly males (77 vs. 44%), presented a higher BMI (25.5 ± 6.2 vs. 21.5 ± 3.6), a larger neck circumference (38 ± 1 vs. 34 ± 1 cm) and a lower Kt/V (2.6 ± 0.3 vs. 2.2 ± 0.1) than patients with no OSA (p < 0.05). Neck circumference and lower Kt/V were independently associated with OSA on multivariate analysis. No patient with Kt/V >2.5 (n = 10) presented OSA. On the other hand, hypertensive patients with OSA needed more BP control pills (p = 0.03). Despite similar BP control, patients with OSA presented a higher interventricular septum thickness (11.5 ± 0.5 vs. 9.9 ± 0.3 mm; p = 0.011). In conclusion, among patients on maintenance hemodialysis, the traditional risk factors for OSA are present and interact with hemodialysis efficiency. Among these patients, OSA is associated with difficult BP control and heart remodeling suggesting that OSA may contribute to poor cardiovascular outcome.

Apoptosis in kidney and pancreas allograft biopsies.

Background. Apoptosis is a particular form of cell death involved in the elimination of somatic cells. In this study, the occurrence of apoptotic cells in kidney and pancreas allograft biopsies was analyzed and correlated with the number of infiltrating macrophages and lymphocytes and granzyme B expression. Methods. Kidney and pancreas biopsies from patients submitted to simultaneous pancreas-kidney transplantation were classified into three groups: acute rejection, chronic rejection, and transplant cases without evidence of rejection. Formalin-fixed paraffin biopsies were used to identify apoptosis by the terminal deoxynucleotidyl transferase [TdT]-mediated dUTP nick end labeling (TUNEL) method. Results. In normal kidney, only few apoptotic cells were observed. In contrast, in kidney-allograft biopsies, the TUNEL signal was detected in the nuclei of tubular epithelial cells and also in mononuclear cells scattered in the interstitium. In pancreas biopsies, numerous apoptotic cells were detected in acinar cells, in ducts, and occasionally in islets. The number of apoptotic cells in acute pancreas rejection was significantly higher compared with acute rejection of kidney grafts (50±14 vs. 21±4 cells/mm2; P<0.05). In kidney biopsies, there was a positive correlation between apoptosis and macrophages (r=0.51; P<0.005), and apoptosis versus T lymphocytes (r=0.45; P<0.05). In pancreas biopsies, the number of apoptotic cells correlated only with the number of macrophages (r=0.41; P<0.05). Conclusions. Apoptosis occurs in kidney and pancreas allograft biopsies, markedly in acute rejection in pancreas biopsies. Although apoptosis may reflect a mechanism of down-regulation of the allograft immune response by eliminating infiltrating cells, the elimination of graft cells may result in graft damage, particularly in pancreas transplantation.

Causes and prognosis of acute renal failure in elderly patients

The prolonged life span of populations is the obvious reason for an increasing proportion of elderly patients with acute renal failure (ARF). The role of age as a factor indicative of a poor prognosis is a matter of controversy. OBJECTIVE: To evaluate this role we have analyzed the final outcome of elderly patients with ARF treated in our Nephrology Service. MATERIAL AND METHODS: Among 361 ARF cases prospectively studied during a two-year period (January 1995 to December 1996), 130 (36%) occurred in patients over 70 years of age. Etiology, clinical course and prognosis were analyzed. The average age was 76.0 ± 4.7 years, varying from 70 to 94 years; 84 patients (65%) were male, and surgical causes accounted for 51% of geriatric ARF. RESULTS: The most frequent causes were: ischemic (volume depletion, arterial hypotension, and/or low cardiac output) in 48 patients (38%), sepsis in 40 (312%), nephrotoxic drugs in 46 (35%) and obstructive abnormalities in 10 (7.7%); in other 14 (11%) they were diagnosed more than a causal agent. Oliguria was present in 37.2% (81 patients), and dialysis was needed in 50 patients (39%). The mortality in the population with age below 70 years was 43% and in the elderly patients was 53.8%; total mortality was similar in both groups of patients (p=0.085). Oliguria, need for dialysis, presence of surgical causes of ARF, and ARF acquired within the intensive care unit were associated with poor prognosis in elderly group. CONCLUSION: We concluded that the percentile of elderly patients with ARF is elevated; they presented mortality about of 50%, and this is not superior to the observed in the youngest population; oliguria, dialysis need, ICU cares and surgery are factors of unfavorable prognostic in these patients.