Search PubMed⌕ Search

Biomedical subjects

S A Draibe

Publications and source records attributed to S A Draibe.

At least 19 recordsLinked to original sources

Resting energy expenditure and its determinants in hemodialysis patients.

OBJECTIVE: Chronic kidney disease is associated with several metabolic disturbances that can affect energy metabolism. As resting energy expenditure (REE) is scarcely investigated in patients on hemodialysis (HD) therapy, we aimed to evaluate the REE and its determinants in HD patients. DESIGN: Cross-sectional study. SETTING: Dialysis Unit of the Nephrology Division, Federal University of São Paulo, Brazil. SUBJECTS: The study included 55 patients (28 male, 41.4+/-12.6 years old) undergoing HD therapy thrice weekly for at least 2 months, and 55 healthy individuals pair matched for age and gender. Subjects underwent fasting blood tests, as well as nutritional assessment, and the REE was assessed by indirect calorimetry. RESULTS: REE of HD patients was similar to that of pair-matched controls (1379+/-272 and 1440+/-259 kcal/day, respectively), even when adjusted for fat-free mass (P=0.24). REE of HD patients correlated positively with fat-free mass (r=0.74; P<0.001) and body mass index (r=0.37; P<0.01), and negatively with dialysis adequacy (r=-0.46; P<0.001). No significant univariate correlation was found between REE and age, dialysis vintage, serum creatinine, urea, albumin, bicarbonate, parathyroid hormone (PTH) or high-sensitivity C-reactive protein (CRP). In the multiple linear regression analysis, using REE as dependent variable, the final model showed that besides the well-recognized determinants of REE such as fat-free mass and age, PTH and CRP were the independent determinants of REE in HD patients (R (2)=0.64). CONCLUSIONS: In this study, the REE of HD patients was similar to that of healthy individuals, even with the positive effect of secondary hyperparathyroidism and inflammation on REE of these patients.

Adult↗

Osteoporosis in hemodialysis patients revisited by bone histomorphometry: a new insight into an old problem.

Osteoporosis in hemodialysis patients is associated with high morbidity and mortality and, although extensively studied by noninvasive methods, has never been assessed through bone biopsy. The aim of this study was to use histomorphometry to evaluate osteoporosis and identify factors related to its development in hemodialysis patients. We conducted a cross-sectional study involving 98 patients (35 women and 63 men; mean age: 48.4 +/- 13 years) on hemodialysis for 36.9 +/- 24.7 months. Patients were submitted to transiliac bone biopsy with double tetracycline labeling. The bone metabolism factors ionized calcium, phosphorus, bone alkaline phosphatase, deoxypyridinoline, intact parathyroid hormone, and 25(OH) vitamin D were evaluated, as were the bone remodeling cytokines osteoprotegerin (OPG), soluble receptor-activator of NF-kappabeta ligand (sRANKL) and tumor necrosis factor-alpha (TNF)alpha. Osteoporosis was defined as trabecular bone volume (BV/TV) greater than 1 s.d. below normal (men <17.4%; women <14.7%). Forty-five patients (46%) presented osteoporosis, which was correlated with white race. We found BV/TV to correlate with age, OPG/sRANKL ratio, TNFalpha levels, and length of amenorrhea. In multiple regression analysis adjusted for sex and age, length of amenorrhea, white race, and OPG/sRANKL ratio were independent determinants of BV/TV. Histomorphometric analysis demonstrated that osteoporotic patients presented normal eroded surface and low bone formation rate (BFR/BS). Osteoporosis is prevalent in hemodialysis patients. Low BFR/BS could be involved in its development, even when bone resorption is normal. Cytokines may also play a role as may traditional risk factors such as advanced age, hypogonadism, and white race.

Adult↗

Short-term effects of a very-low-protein diet supplemented with ketoacids in nondialyzed chronic kidney disease patients.

OBJECTIVE: To evaluate the effects on the nutritional and metabolic parameters of a very-low-protein diet supplemented with ketoacids (VLPD+KA) in comparison with a conventional low-protein diet (LPD) in chronic kidney disease (CKD) patients. DESIGN: Prospective, randomized, controlled clinical study. SETTING: Outpatient Clinic of the Nephrology Division of Federal University of Sao Paulo, Brazil. SUBJECTS: The study involved 24 patients with advanced CKD (creatinine clearance <25 ml/min) that were randomly assigned to either a VLPD+KA (VLPD+KA group, 12 patients) or to a conventional LPD with 0.6 g/kg/day (LPD group, 12 patients). The patients were followed for 4 months. RESULTS: Nutritional status was adequately maintained with both diets for the studied period. Protein intake and serum urea nitrogen decreased significantly only in the VLPD+KA group (from 0.68+/-0.17 to 0.43+/-0.12 g/kg/day, P<0.05; from 61.4+/-12.8 to 43.6+/-14.9 mg/dl, P<0.001; respectively). Ionized calcium did not change in the VLPD+KA group but tended to decrease in the LPD group. Serum phosphorus tended to decrease in the VLPD+KA group probably as a result of a significant reduction in dietary phosphorus (529+/-109 to 373+/-125 mg/day, P<0.05) associated to the phosphorus-binding effect of the ketoacids. No change in these parameters was found in the LPD group. Serum parathormone increased significantly only in the LPD group (from 241+/-138 to 494+/-390 pg/ml, P<0.01). The change in PTH concentration was negatively correlated with changes in ionized calcium concentration (r=-0.75, P=0.02) and positively correlated with changes in serum phosphorus (r=0.71, P=0.03) only in the LPD group. CONCLUSION: This study indicates that a VLPD+KA can maintain the nutritional status of the patients similarly to a conventional LPD. Besides, an improvement in calcium and phosphorus metabolism and a reduction in serum urea nitrogen were attained only with the VLPD+KA. Thus, VLPD+KA can constitute another efficient therapeutic alternative in the treatment of CKD patients.

Adult↗

High prevalence of low bone mineral density in pre-dialysis chronic kidney disease patients: bone histomorphometric analysis.

UNLABELLED: Chronic kidney disease (CKD) leads to reduced bone mineral density (BMD) in pre-dialysis and dialysis patients. A few studies have used dual-energy x-ray absorptiometry (DEXA) to assess BMD in pre-dialysis CKD patients and have shown low BMD to be highly prevalent. Until now there have been no studies reporting the histological features of low BMD in pre-dialysis CKD patients. AIM: To determine the prevalence and histological features of low BMD in pre-dialysis CKD patients. METHOD: Pre-dialysis CKD patients (n = 103, 46 females/57 males), median creatinine clearance of 29 (10 - 78) ml/min/ 1.73 m2, were evaluated using biochemical analysis and DEXA. Bone biopsies were obtained from those with low BMD. RESULTS: Fifty (48.5%) out of the 103 patients had low BMD (LBD group) and 53 (51.5%) had normal BMD (NBD group). The risk for low BMD was increased in those patients with alkaline phosphatase levels above 190 U/l and intact-PTH (iPTH) below 70 pg/ml (p < 0.05). Demographic and biochemical parameters from both groups were comparable, except for lower body mass index (BMI) in LBD subjects (p = 0.04). Women who had been post-menopausal for at least 1 year comprised 65% (13/20) and 50% (13/26) of the LBD and NBD groups, respectively (p = NS). In 40 LBD patients, bone histomorphometry revealed adynamic bone disease (ABD, 52.5%), osteomalacia (OM, 42.5%) and mixed bone disease (MBD, 5%). Trabecular bone volume (BV/TV) was lower in ABD and OM patients. A nearly significant association was found between ABD and iPTH < or = 150 pg/ml (p = 0.056), whereas higher values of iPTH were associated with OM. Total alkaline phosphatase < or = 190 U/l was significantly associated with ABD, whereas higher values were associated with OM. No correlation was observed between BV/TV and BMD. CONCLUSION: Low BMD is frequent in pre-dialysis CKD patients, and low turnover bone disease, manifesting as ABD and OM, was the hallmark of this bone loss.

Absorptiometry, Photon↗

Influence of renal function on spontaneous dietary intake and on nutritional status of chronic renal insufficiency patients.

OBJECTIVE: To analyze the spontaneous food intake and the nutritional parameters of patients with different degrees of chronic renal insufficiency (CRI) at the onset of predialysis treatment. DESIGN: Cross-sectional. SETTING: Outpatient Clinic of the Nephrology Division of Federal University of São Paulo, Brazil. SUBJECTS: The analysis involved 487 (187 women and 300 men) patients with moderate to advanced CRI who were evaluated in the first visit to the clinic. RESULTS: Patients were divided according to creatinine clearance (CrCl) quartiles. CrCl in the first quartile was lower than 19.9 ml/min/1.73 m(2) and in the fourth one was higher than 43 ml/min/1.73 m(2). Energy intake was significantly (P<0.05) lower in the first quartile when compared with the fourth one while protein intake estimated by protein equivalent of nitrogen appearance (PNA) was significantly lower in the first, second and third quartiles in comparison with the fourth (P<0.05). Body mass index (BMI) and percentage of ideal body weight were significantly decreased in the three lowest levels of renal function. Standard per cent of triceps skinfold thickness was lower in the first quartile when compared with the fourth one. Compared with the fourth quartile, standard per cent of midarm muscle circumference (MAMC) was lower in the second and in the third quartile. CrCl correlated directly and significantly with PNA (r=0.30; P<0.01), energy intake (r=0.17; P<0.01), and MAMC (r=0.20; P<0.01). In a multiple linear regression analysis, controlling for energy and protein intake, CrCl correlated significantly and positively with BMI and MAMC. CONCLUSION: This study suggests that a spontaneous decrease in energy and protein intake as well as in anthropometric indices follows a decline in renal function in patients with no previous dietary intervention.

Creatinine↗

Risk of bacterial infection in patients under intravenous iron therapy: dose versus length of treatment.

Some studies have suggested that intravenous iron therapy may be associated with an increased risk of infection. We analyzed the incidence of bacterial infection in 111 hemodialysis patients. Group 1 (n = 39, transferrin saturation <20%) received 10 doses of 100 mg of intravenous iron saccharate, 3 doses per week (28 treatment days); Group 2 (n = 13, transferrin saturation <20%) received 20 doses, 3 doses per week (70 treatment days); and Group 3 (n = 59, transferrin saturation 20-50%) received 10 doses, 1 dose per week (70 treatment days). The follow-up was 150 days for all groups, and all infectious episodes were recorded. Pulmonary infection was the most frequent event observed in all of the groups. In an incidence-density analysis, Group 2, which received a total of 20 doses, presented a significantly higher incidence of infection than Group 3, which received only 10 doses over the same period (0.13 versus 0.06 infections per patient per month, p = 0.04). No difference was observed between Groups 1 and 2 suggesting that the risk of infection during iron therapy is dose dependent rather than time length dependent.

Adult↗

Resting energy expenditure in pre-dialysis diabetic patients.

BACKGROUND: The metabolic derangements of diabetes mellitus (DM) associated with those of chronic renal failure (CRF) may interfere with the energy and protein balance of patients with both diseases. The aim of this study was to verify whether the resting energy expenditure (REE) of non-dialysis chronic renal failure diabetic patients differs from that of chronic renal failure patients without DM. METHODS: REE was measured by indirect calorimetry in 24 CRF diabetic patients (CRF diabetes group), matched for age, gender, and degree of renal impairment to 24 CRF patients without DM (CRF control group). RESULTS: The CRF diabetes group had a significantly higher REE (1538+/-230 kcal/day) than the CRF control group (1339+/-315 kcal/day, P = 0.009). This difference was maintained even when the REE was adjusted for lean body mass (LBM; 30.3+/-4.3 vs 26.3+/-5.4 kcal/kg LBM/day, P = 0.004). Mean protein intake was significantly higher in the CRF diabetes than in the CRF control group (0.89+/-0.20 vs 0.76+/-0.25 g/kg/day, P = 0.02). Mean protein equivalent of nitrogen appearance (PNA) was also significantly higher in the CRF diabetes patients (1.21+/-0.31 vs 1.03+/-0.22 g/kg/day, P = 0.02), reflecting a higher protein intake and/or elevated protein breakdown. Accordingly, REE was directly correlated with PNA mainly in the CRF diabetes group (r = 0.57, P < 0.003). CONCLUSION: Metabolic disturbances of poorly controlled DM may account for the higher REE observed in the CRF diabetes group. The role of the apparently higher protein breakdown in this increased REE remains to be clarified.

Aged↗

Parathyroid hormone changes during phosphorus load in patients with chronic renal insufficiency with low serum parathyroid hormone or adynamic bone disease.

UNLABELLED: Adynamic bone disease (ABD) is frequently associated with low serum parathyroid hormone (PTH) concentrations. Many clinical and therapeutic conditions have been associated with ABD, and recently, a low phosphorus intake accompanied by low serum concentration of phosphorus and PTH has been described. AIM: To evaluate the parathyroid gland response of chronic renal insufficiency patients (CRI) with low serum PTH or ABD to a phosphorus load. METHODS: We examined the effects of 0.5 and 1.0 g/d of phosphorus load over a period of 60 days in 18 patients with mild CRI with a bone biopsy showing ABD (n = 7) or with low serum PTH (serum intact PTH < or = 40 ng/l) and serum phosphorus < 4.5 mg/dl (n = 11). RESULTS: Serum intact PTH increased significantly only after 1 g of phosphorus (58.5 to 83 ng/l) with a median percent increase of 72%. PTH secretion increased more in patients with lower basal PTH levels (81%). Serum phosphorus did not change significantly and urinary phosphorus increased from 487 to 1,062 mg/dl (p < 0.05). Significant decreases in serum ionized calcium (from 1.26 to 1.19 mmol/l) and calcitriol (from 34.5 to 24.9 pg/ml) were observed. Changes in PTH were inversely correlated with changes in serum ionized calcium (r = -0.54, p < 0.05) and the final PTH concentrations were positively correlated with changes in serum phosphorus (r= 0.52, p < 0.05). CONCLUSIONS: The parathyroid glands of chronic renal insufficiency patients with "relative hypoparathyroidism" or ABD responded to a phosphorus load with an increase in serum PTH levels. The decrease in serum ionized calcium and calcitriol as well as minimal changes in serum phosphorus appeared to be involved in this response.

Adult↗

Nutritional status of hemodialysis patients with secondary hyperparathyroidism.

The repercussions of secondary hyperparathyroidism on the nutritional status of chronic renal failure patients have not been well established. Therefore, the aim of this study was to compare the nutritional indices of hemodialysis patients with and without secondary hyperparathyroidism. Sixteen hemodialysis patients with serum parathyroid hormone (PTH) levels higher than 420 pg/ml (hyperparathyroidism group) were matched for gender, age and length of dialysis treatment to 16 patients with serum PTH between 64 and 290 pg/ml (control group). The following parameters were assessed: anthropometric indices (body mass index, skinfold thickness, midarm muscle circumference and body fat), 4-day food diaries, protein catabolic rate, biochemical indices (blood urea nitrogen, serum creatinine, albumin, ionized calcium, inorganic phosphorus, serum alkaline phosphatase, PTH, pH and HCO(3)) and dialysis efficiency. We did not observe differences in the anthropometric indices between the two groups. Only calcium intake was significantly different between groups (307.9 mg/day for the hyperparathyroidism group vs 475.8 mg/day for the control group). Protein catabolic rate tended to be higher in the hyperparathyroidism group compared to the control group (1.3 vs 0.9 g kg(-1) day(-1); P = 0.08). Except for blood urea nitrogen (86.4 vs 75.7 mg/dl), alkaline phosphatase (175 vs 65 U/l) and PTH (898 vs 155 pg/ml), no other differences were found between groups in the biochemical indices studied. PTH was directly correlated with protein catabolic rate (r = 0.61; P<0.05) and length of dialysis (r = 0.53; P<0.05) only in the hyperparathyroidism group. Considering the indices used, we could not demonstrate the deleterious effect of high PTH levels on the nutritional status of hemodialysis patients. Indirect evidence, however, suggests an action of PTH on protein metabolism.

Adult↗

Effect of etidronate treatment on bone mass of male nephrolithiasis patients with idiopathic hypercalciuria and osteopenia.

Osteopenia is frequently found among calcium stone forming (CSF) patients with hypercalciuria. We investigated the effect of a 2-year therapeutic course of etidronate, a bone-sparing agent, in 7 young male CSF patients. The treatment consisted of a cyclic intermittent administration of phosphate followed by sodium etidronate and calcium supplementation every 74 days. Bone mineral density (BMD) measured at 12-month intervals and bone biopsies performed at baseline and after 2 years were the primary efficacy parameters. Mean lumbar spine BMD increased significantly after the 1st year by 2.6 +/- 1.0% (mean +/- SE, p < 0.05) and nonsignificantly after the 2nd year by 5.6 +/- 2.6%. Nonsignificant changes were observed for femoral neck mean BMD after either the 1st or the 2nd year (decrease of 2.0 +/- 1.0% and 2.0 +/- 3.0%, respectively). Mean histomorphometric parameters showed that bone volume, osteoid volume, and eroded surfaces did not differ from baseline (13.9 +/- 2.2 vs. 12.2 +/- 1.1%, 1.2 +/- 0.7 vs. 2.6 +/- 0.7%, and 20.7 +/- 6.2 vs. 13. 7 +/- 1.3%, respectively). Osteoid surface was significantly lower than baseline values (9.5 +/- 5.2 vs. 18.8 +/- 5.3%, p < 0.05). These data suggest that etidronate given to young male CSF patients presenting with hypercalciuria and osteopenia led to a significant amelioration of BMD, evident only in the lumbar spine after 1 year of treatment. There was no histological evidence of long-term improvement in bone remodeling.

Adult↗

A retrospective study of kidney transplant recipients from living unrelated donors.

Due to the shortage of cadaveric organs, kidneys from living unrelated donors (LUD) are increasingly being used for transplantation. The long-term outcome for LUD recipients is not completely known. This study was undertaken to evaluate the long-term graft survival in LUD recipients and compare it with that of cadaver donor allograft recipients. Three hundred and sixty-four LUD and 3881 cadaveric kidney recipients were evaluated using data obtained through the Brazilian Renal Transplant Registry. Transplants performed between January 1, 1987, and June 30, 1996, were eligible for analysis. Graft and patient survival were estimated by the Kaplan-Meier method. Sixty percent of the LUD were from spouses. The median duration of follow-up was 23.8 mo (0 to 117.2 mo). Patient survival rates were not significantly different for LUD and cadaveric kidney recipients (69% [95% confidence interval (CI), 61.9 to 76.1%] versus 73.2% [71 to 75.4%] at 5 yr; 69% [61.9 to 76.1%] versus 60.6% [55.1 to 66.1%] at 9.6 yr). Graft survival rates for recipients of LUD allografts were similar to those for cadaveric kidneys at 5 yr (50.1% [43.2 to 57%] versus 50.4% [48.1 to 52.8%]) and higher, although not significantly, at 9.6 yr (45.7% [37.7 to 53.7%] versus 32.7% [26.4 to 39%], respectively, P = 0.14). In a multivariate analysis using the Cox proportional hazards regression model, after adjusting for recipient age, race, history of previous transplantation, and year of transplantation, the risk of graft failure was 16% (95% CI, -3% to 31%) lower for LUD than cadaveric recipients. We conclude that LUD are an excellent alternative to cadaveric kidney donors. The long-term patient and graft survival rates for recipients of LUD allografts are at least as good as those for recipients of cadaveric kidneys.

Adult↗

Sensitivity to calcium intake in calcium stone forming patients.

The absorptive or renal origin of hypercalciuria can be discriminated using an acute oral calcium load test (ACLT). Of 86 patients with calcium oxalate kidney stones, 28 (23%) were found to be hypercalciuric (HCa) and 58 (67%) normocalciuric (NCa) on their customary free diet, containing 542 +/- 29 mg/day (mean +/- SE) of calcium. Since the apparently normal 24-hour calcium excretion of many calcium stone formers (CSF) may be due to a combination of high calcium absorption with moderately low calcium intake, all patients were investigated by ACLT. Of 28 HCa patients, 13 (46%) were classified as absorptive (AH) and 15 (54%) as renal hypercalciuria (RH). Of the 58 NCa patients, 38 (65%) presented features of intestinal hyperabsorption and were therefore designated as AH-like, and 20 (35%) as RH-like. To further elucidate the role of dietary calcium in these CSF, a chronic calcium load test (CCLT), consisting of 1 g/day of oral Ca for 7 days, was designed. A positive response to the CCLT was considered to occur when urinary calcium (uCa) was > or = 4 mg/ kg/24 h on the 7th day. Among NCa patients, 29% of AH-like subjects responded to the CCLT and 71% did not; 50% of RH-like subjects also responded and 50% did not. In HCa patients, 85% of AH and 67% of RH subjects maintained uCa > or = 4 mg/kg/24 h after the CCLT and 15% of AH and 23% of RH subjects did not. However, a significant additional increase in mean uCa was not observed among HCa patients. All patients were submitted to a second evaluation of fasting calciuria (Ca/Cr). A modification of this parameter was noticed in 89% of RH-like and 78% of RH patients. In conclusion, these data suggest the presence of subpopulations of patients sensitive or not to calcium intake, regardless of whether the acute response to a calcium overload test suggested AH or RH. The CCLT disclosed dietary hypercalciuria in 21/58 (36%) of previously NCa patients. In these NCa patients, the ACLT may be replaced by the CCLT. The distinction between AH and RH initially evidenced by the ACLT was not further confirmed. These data suggest that either fasting Ca/Cr is not adequate for subclassification of HCa or that AH and RH represent a different spectrum of the same disease, and that a primary resorptive component should also be considered.

Calcium↗

Hemodialysis versus continuous ambulatory peritoneal dialysis: effects on the heart.

In this study we compared the influence of 2 different modalities of treatment, CAPD and hemodialysis, on the prevalence and severity of left ventricular hypertrophy and cardiac arrhythmias of chronic renal failure patients. We compared 27 patients on the CAPD program with 27 patients on the chronic hemodialysis matched for sex, age, and duration of dialysis treatment. The prevalence of hypertension was significantly lower in CAPD than in hemodialysis patient (41% vs. 81%, p = 0.0023). Blood pressure levels were also lower in CAPD than in hemodialysis patients (systolic pressure 124.9 +/- 4.7 vs. 154.8 +/- 4.6 mm Hg, p < 0.0001; diastolic pressure 77.5 +/- 2.9 vs. 93.3 +/- 2.8 mm Hg, p = 0.0001). Left ventricular hypertrophy (LVH) was present in 52% of CAPD and in 93% of hemodialysis patients (p = 0.0008). Severe cardiac arrhythmias (Lown 3-4) occurred in only 4% of CAPD and in 33% of the hemodialysis group (p = 0.0149). The lower frequency of LVH in CAPD might explain the lower incidence of severe arrhythmias.

Adult↗

Environmental transmission of hepatitis B and hepatitis C viruses within the hemodialysis unit.

The hepatitis B virus (HBV) can be transmitted in the dialysis setting through blood transfusions and environmental surfaces. Transfusion related hepatitis C virus (HCV) infection is very well known, but only recently the environmental transmission of this virus was postulated. In order to study the prevalence, mechanisms of transmission, and the ALT patterns of HBV and HCV infections in hemodialysis and CAPD patients before the implementation of HBV vaccination and HCV screening in the blood bank, we conducted a study from January 1987 to January 1990. Sera from 185 hemodialysis and 124 CAPD patients were stored in this period and later analyzed for HBsAg, anti-HBc, anti-HBs, and anti-HCV (second generation ELISA). The prevalence of any HBV marker was 55.7% (103/185) for hemodialysis patients and 31.5% (39/124) for CAPD patients (hemodialysis vs. CAPD, p < 0.001). The prevalence of positive anti-HCV was 35.1% (65/185) for hemodialysis and 33.9% (42/124) for CAPD patients (not significant). There was a significant association between HBV markers positivity and anti-HCV positivity. The multivariate analysis of risk factors revealed an association of the positivity of each virus with the duration of renal replacement therapy (RRT), number of previous blood transfusions, and past history of hemodialysis treatment. Thus, besides the transfusion-related transmission, hemodialysis environmental transmission may also occur for both viruses. The findings of a high prevalence of both viruses and evidence for environmental transmission in the dialysis setting are of major importance for the planning of future preventive measures.

Adolescent↗

Incidence of and risk factors for hepatitis B virus and hepatitis C virus infection among haemodialysis and CAPD patients: evidence for environmental transmission.

Hepatitis B virus (HBV) serum markers (HBsAg, anti-HBs, anti-HBc) and antihepatitis C antibody (anti-HCV) were prospectively followed in haemodialysis and CAPD patients. From January 1987 to January 1990, 185 patients on haemodialysis and 124 on CAPD were analysed. Among patients susceptible to HBV (69 on haemodialysis and 70 on CAPD), there were 17 HBsAg seroconversions on haemodialysis (0.19/patient-year) and 1 on CAPD (0.01/patient-year). A Cox proportional hazards model showed that haemodialysis treatment was the only risk factor significantly associated with HBV infection, thus suggesting transmission through the environment. Regarding hepatitis C, 83 anti-HCV-negative patients on haemodialysis and 46 on CAPD were followed. There were 18 seroconversions on haemodialysis (0.15/patient-year) and two seroconversions on CAPD (0.03/patient-year). Haemodialysis treatment was also the only risk factor significantly associated with a higher risk of HCV infection. The hazard ratio for HCV infection in haemodialysis patients was 5.7 compared to CAPD patients. Nevertheless, for one patient on CAPD treatment transfusions were the only possible source of HCV infection. In conclusion, both viruses were transmitted mainly through the haemodialysis environment, but the role of transfusions could not be excluded.

Adolescent↗

Glomerular hemodynamics during abortion induced by RU 486 and sepsis in rats.

1. Acute renal failure is a very common consequence of septic abortion. Whole kidney and glomerular hemodynamics were evaluated in virgin (V), pregnant (PREG) and aborted (ABOR) euvolemic Munich-Wistar rats before and after E. coli (0111-B4) endotoxin (LPS) infusion in order to evaluate the effect of septic abortion on the renal microcirculation. 2. Abortion induced by RU 486 blunted the increase in glomerular filtration rate (GFR) induced by normal pregnancy (0.86 +/- 0.03 vs 0.63 +/- 0.07 ml/min, P < 0.05). In virgin rats, RU 486 did not modify the parameters of renal function. Significant alterations occurred in whole kidney and single nephron function. However, the changes in whole kidney function in the ABOR group were significantly higher than those observed for the V group (reductions in GFR were 42% in V and 80% in ABOR, RPF decreased 34% in V and 76% in ABOR, TRVR increased 82% in V and 400% in ABOR). 3. Mean single nephron glomerular filtration rate (SNGFR) was reduced in all groups after LPS (44% in V, 43% in V+RU, 55% in PREG, 60% in ABOR), due to significant decreases in glomerular plasma flow rate, QA (42% in V, 55% in V+RU, 53% in PREG, 57% in ABOR) and in glomerular ultrafiltration coefficient, Kf (46% in V, 47% in V+RU, 45% in PREG, 67% in ABOR). 4. These data show that LPS induced significant alterations in renal function in all groups. However, aborted rats were more sensitive to the effects of LPS than V rats. These results indicate that abortion may potentiate the effects of endotoxemia on renal function elevating the extent of acute renal failure and thus the mortality rate.

Abortion, Induced↗

Bone disease in calcium stone forming patients.

The association between idiopathic hypercalciuria and osteopenia (OP) has been recently recognized. It is not established whether or not calcium intake plays a critical role in the loss of bone mass. Fifty-five calcium stone forming patients with either absorptive hypercalciuria (AH) or fasting hypercalciuria (FH), 29 males and 26 premenopausal females, were submitted to dual photon absorptiometry at lumbar spine. Calcium intake was assessed by a 72 hr dietary record. OP was detected in 20% (11/55) of patients, being more common among men, 9/26 (35%) than in women, 2/29 (7%), p < 0.05. Male FH patients presented lower mean bone mineral density (BMD) than sex, weight and age-matched control (1.058 +/- 0.18 vs 1.209 +/- 0.13 g/cm2, X +/- SD, p < 0.05). OP was more frequent in FH patients, 7/20 (35%) than in AH patients 4/35 (11%), albeit the difference was not statistically significant. There was no correlation between calcium intake and BMD measurement. Six osteopenic male FH patients were further submitted to histomorphometric evaluation with tetracycline double labeling. Bone volume was lower than the controls (13.2 +/- 3.0 vs 27.2 +/- 3.7%, p < 0.05). Osteoid surfaces were reduced, although not significantly (10.1 +/- 8.2% vs 15.9 +/- 6.7%). Eroded surfaces were markedly increased (23.9 +/- 13.4 vs 4.2 +/- 1.4%, p < 0.05). The bone formation rate was very low with a complete lack of tetracycline double labeling in 4 patients. These data suggest low bone volume, tendency to low bone formation, increased bone resorption and a severe mineralization defect, consistent with normal or low bone turnover osteoporosis.

Absorptiometry, Photon↗