Risk factors for death and changing patterns in leptospirosis acute renal failure.
The risk factors for death and changes in clinical patterns in leptospirosis (Weil's disease) have not been well studied. We retrospectively studied 110 patients with Weil's disease hospitalized in Brazil between 1985 and 1996. Univariate statistical analysis showed that nonsurvivors were older than survivors, and had higher frequency of oliguria, cardiac arrhythmia, dyspnea, and pulmonary rales. Logistic regression showed that the only independent factor associated with death was oliguria (odds ratio [OR] = 8.98). The presence of arthralgia (OR = 4.71), dehydration (OR = 6.26), dyspnea (OR = 17.7), and pulmonary rales (OR = 9.91) increased after 1994. These data suggest that in Weil's disease the clinical patterns have changed and the presence of oliguria is a risk factor for death. (+info)
Nutritional aspects of high-altitude exposure in women.
The nutrient intake and urinary excretion characteristics of eight young university women were studied over a 4-day period at low altitude (140 m) and subsequently over a 7-day sojourn on Pikes Peak (4,300 m). High-altitude exposure was associated with a transient decrease in the consumption of protein, carbohydrate, fat, sodium, calcium, phosphorus, vitamin A, riboflavin, thiamin, and niacin and a more sustained decrease in the consumption of potassium and ascorbic acid. In most instances minimal values were observed during the first 3 days of exposure. The carbohydrate fraction of energy intake was increased at the expense of fat during this time period. Individual hypophagic responses appeared to be related to severity of acute mountain sickness. Altitude had no effect on water consumption but did lead to an average body weight loss of 1 kg. Urinary measurements revealed a marked oliguria during the entire sojourn. These measurements also showed the first 3 days to be associated with a net loss of body nitrogen and sodium. During this time period body potassium and phosphorus were conserved, and probably increased. The urea fraction of body potassium and phosphorus were conserved, and probably increased. The urea fraction of total urinary nitrogen was not affected by altitude exposure, nor was the daily excretion of uric acid and creatinine. Ammonia excretion, however, was reduced to 50% of the low-altitude value and remained at this level throughout the sojourn. With a few exceptions, the qualitative characteristics of altitude hypophagia in women were similar to those reported for men. Quantitatively, however, the responses were much more transient in women. (+info)
Treatment-related acute renal failure in the elderly: a hospital-based prospective study.
BACKGROUND: Elderly individuals need a host of diagnostic procedures and therapeutic interventions to take care of ailments. This prospective study was carried out to determine the magnitude of treatment-related acute renal failure (ARF) in the elderly in a hospital setting, to know about pathogenetic factors and to study the factors that could predict an adverse outcome. METHODS: All elderly patients (>60 years) admitted over a 12-month period were screened prospectively throughout their hospital stay for the development of ARF. RESULTS: Of 31860 patients admitted, 4176 (13%) were elderly. Of these 59 (1.4%) developed ARF in the hospital. Nephrotoxic drugs contributed towards development of ARF in 39 (66%), sepsis and hypoperfusion in 27 (45.7%) each, contrast medium in 10 (16.9%) and postoperative ARF occurred in 15 (25.4%) patients. These pathogenetic factors were responsible for ARF in different combinations. Amongst these combination of pathogenetic factors, radiocontrast administration (partial chi(2) 28.1, P<0.0001), surgery (partial chi(2) 14.89, P=0.001), and drugs (partial chi(2) 6. 22, P=0.0126) predicted ARF on their own. Nine patients (15.23%) needed dialytic support. Of 59 patients, 15 (25.4%) died, of those who survived, 38 (86.3%) recovered renal function completely and six (13.6%) partially. Mortality in the elderly with ARF was significantly higher than in those without ARF (25.4 vs 12.5%; chi(2) 8.3, P=0.03). Sepsis (odds ratio 43), oliguria (odds ratio 64), and hypotension (odds ratio 15) were independent predictors of poor patient outcome on logistic regression analysis. CONCLUSION: Incidence of treatment-related ARF in the elderly was 1.4%, with more than one pathogenetic factor playing a role in the development of ARF in the majority. Sepsis, hypotension, and oliguria were the independent predictors of poor patient outcome. (+info)
The mechanism of acute renal failure after uranyl nitrate.
Administration of 25 mg/kg uranyl nitrate (UN) to rats leads to a brief period of polyuria followed by progressive oliguria with death at 5 days. Factors that determine glomerular filtration rate (GFR) were examined in control Munich-Wistar rats (n equals 16) and 2 h after either 15 mg/kg (n equals 8) or 25 mg/kg (n equals 7) of UN (i.v.) utilizing direct measurements of hydrostatic and oncotic pressures and plasma flow. Total kidney GFR was reduced to 47% of control in the low dose group and to 21% in the high dose group. The simultaneous nephron filtration rate (sngfr) was 28.6 plus or minus 0.8 nl/min/g kidney wt in control, 29.1 plus or minus 1.0 in the low dose group, and 18.1 plus or minus 1.2 (P less than 0.001) in the higher dose group. This disparity in UN effect upon GFR and sngfr was due to tubular back-diffusion of solute through damaged epithelia beyond the early proximal tubule as demonstrated by microinjection of inulin and mannitol in the proximal tubule. Inulin "leak" persisted at 6 h after UN when tubular pressure had returned to normal. Comparison of sngfr measured in early vs. late proximal tubule revealed no difference after high dose UN, suggesting no significant leak of inulin from the early proximal tubule, and that the decreased sngfr was due to primary reductions in ultrafiltration. Nephron plasma flow was equal to control at both doses of UN. Also directly measured hydrostatic pressure gradient across the glomerular capillary was not changed. The effective filtration pressure achieved equilibrium in control of animals but became significantly positive at the efferent end of the capillary at both doses of UN and increased. Total glomerular permeability (LpA) was progressively reduced from control (0.089 plus or minus 0.005 nl/s/g kidney wt/mm Hg) at low dose UN (0.047 plus or minus 0.013) and high dose 0.024 plus or minus 0.003 nl/s/g kidney wt/mm Hg). Therefore UN decreases GFR by two mechanisms: (1) tubular damage leading to back-diffusion of solutes and (b) a primary reduction in sngfr due to reduced LpA. (+info)
Use of radionuclide imaging in the early diagnosis and treatment of renal allograft rejection.
Data are presented on the clinical application of radionuclide imaging to evaluate changes in cadaver transplant function in the immediate postoperative period. The method uses orthoiodohippuric acid (hippuran) administered IV, with scintillation imaging, and curve analysis by a digital computer. An initial study is always obtained 24 hours after transplantation. Serial studies are then obtained, as needed, to interpret the clinical course. Selected cases are presented which illustrate the use of this protocol in various clinical settings. In the oliguric patient serial studies have been of particular value. They have identified ATN so that over-enthusiastic treatment for rejection could be avoided. They have also identified acute rejection complicating ATN so that high dose steroid therapy could be administered appropriately. In the non-oliguric patient they have frequently contributed to the early diagnosis of acute rejection, and they have been useful in monitoring the effect and duration of treatment for severe rejection crisis. It is concluded that radionuclide imaging studies, when carefully applied and interpreted, are a valuable adjunct to the management of patients in this complex clinical setting. (+info)
A comparison of ibuprofen and indomethacin for closure of patent ductus arteriosus.
BACKGROUND: Indomethacin is the conventional treatment for hemodynamically important patent ductus arteriosus in preterm infants. However, its use is associated with various side effects. In a prospective study, we compared ibuprofen and indomethacin with regard to efficacy and safety for the early treatment of patent ductus arteriosus in preterm infants. METHODS: We studied 148 infants (gestational age, 24 to 32 weeks) who had the respiratory distress syndrome and an echocardiographically confirmed, hemodynamically important patent ductus arteriosus. The infants were randomly assigned at five neonatal intensive care centers to receive three intravenous doses of either indomethacin (0.2 mg per kilogram of body weight, given at 12-hour intervals) or ibuprofen (a first dose of 10 mg per kilogram, followed at 24-hour intervals by two doses of 5 mq per kilogram each), starting on the third day of life. The rate of ductal closure, the need for additional treatment, side effects, complications, and the infants' clinical course were recorded. RESULTS: The rate of ductal closure was similar with the two treatments: ductal closure occurred in 49 of 74 infants given indomethacin (66 percent), and in 52 of 74 given ibuprofen (70 percent) (relative risk, 0.94; 95 percent confidence interval, 0.76 to 1.17; P=0.41). The numbers of infants who needed a second pharmacologic treatment or surgical ductal ligation did not differ significantly between the two groups. Oliguria occurred in 5 infants treated with ibuprofen and in 14 treated with indomethacin (P=0.03). There were no significant differences with respect to other side effects or complications. CONCLUSIONS: Ibuprofen therapy on the third day of life is as efficacious as indomethacin for the treatment of patent ductus arteriosus in preterm infants with the respiratory distress syndrome and is significantly less likely to induce oliguria. (+info)
Effect of the selective adenosine A1-receptor antagonist KW-3902 on lipopolysaccharide-induced reductions in urine volume and renal blood flow in anesthetized dogs.
We investigated the effects of KW-3902 (8-noradamantan-3-yl-1,3-dipropylxanthine), a potent and selective adenosine A1-receptor antagonist, on lipopolysaccharide (LPS)-induced reduction of urine volume (UV) in anesthetized dogs, in comparison with those of furosemide. LPS was intravenously administered at a dose of 0.5 mg/kg; and the heart rate (HR), systemic blood pressure (BP), renal blood flow (RBF) and UV were measured every 15 min for 4 h. Administration of LPS continuously decreased HR, BP, RBF and UV. KW-3902, furosemide or their corresponding vehicle was given as a bolus injection 5 min after the LPS injection. Treatment with KW-3902 (1 mg/kg, i.v.) ameliorated the LPS-induced decline of UV and RBF. Furosemide (3.2 mg/kg, i.v.) tended to ameliorate the LPS-induced decline of UV but not RBF, the duration of the effect being shorter than that of KW-3902. These results suggest that KW-3902 can ameliorate the oliguria and the decrease in RBF during the early phase of LPS-induced shock. Endogenous adenosine may be involved in the endotoxin-induced oliguria via the adenosine A1-receptor. (+info)
Daily hemodialysis and the outcome of acute renal failure.
BACKGROUND: Intermittent hemodialysis is widely used as renal-replacement therapy in patients with acute renal failure, but an adequate dose has not been defined. We performed a prospective study to determine the effect of daily intermittent hemodialysis, as compared with conventional (alternate-day) intermittent hemodialysis, on survival among patients with acute renal failure. METHODS: A total of 160 patients with acute renal failure were assigned to receive daily or conventional intermittent hemodialysis. Survival was the primary end point of the study. The duration of acute renal failure and the frequency of therapy-related complications were secondary end points. RESULTS: The two study groups were similar with respect to age, sex, cause and severity of acute renal failure, medical or surgical intensive care setting, and the score on the Acute Physiology, Age, and Chronic Health Evaluation. Daily hemodialysis resulted in better control of uremia, fewer hypotensive episodes during hemodialysis, and more rapid resolution of acute renal failure (mean [+/-SD], 9+/-2 vs. 16+/-6 days; P=0.001) than did conventional hemodialysis. The mortality rate, according to the intention-to-treat analysis, was 28 percent for daily dialysis and 46 percent for alternate-day dialysis (P=0.01). In a multiple regression analysis, less frequent hemodialysis (on alternate days, as opposed to daily) was an independent risk factor for death. CONCLUSIONS: The high mortality rate among critically ill patients with acute renal failure who require renal-replacement therapy is related to both coexisting conditions and uremic damage to other organ systems. Intensive hemodialysis reduces mortality without increasing hemodynamically induced morbidity. (+info)