Standard WHO-ORS versus reduced-osmolarity ORS in the management of cholera patients. Multicenter, randomized, double-blind clinical trial to evaluate the efficacy and safety of a reduced osmolarity oral rehydration salts solution in children with acute watery diarrhea. A double-blind clinical trial comparing World Health Organization oral rehydration solution with a reduced osmolarity solution containing equal amounts of sodium and glucose. Is a low-osmolarity ORS solution more efficacious than standard WHO ORS solution? Efficacy and safety of oral rehydration solution with reduced osmolarity in adults with cholera: a randomised double-blind clinical trial. CHOICE study group. Multicentre evaluation of reduced-osmolarity oral rehydration salts solution. International Study Group on Reduced-osmolarity ORS solutions. Efficacy of standard glucose-based and reduced-osmolarity maltodextrin-based oral rehydration solutions: effect of sugar malabsorption. Alanine- and glucose-based hypo-osmolar oral rehydration solution in infants with persistent diarrhoea: a controlled trial. Reduced osmolarity oral rehydration salt in Cholera.
The study compared the safety and efficacy of an oral rehydration salts (ORS) solution, containing 75 mmol/L of sodium and glucose each, with the standard World Health Organization (WHO)-ORS solution in the management of ongoing fluid losses, after initial intravenous rehydration to correct dehydration. The study was conducted among patients aged 12-60 years hospitalized with diarrhoea due to cholera. One hundred seventy-six patients who were hospitalized with acute diarrhoea and signs of severe dehydration were rehydrated intravenously and then randomly assigned to receive either standard ORS solution (311 mmol/L) or reduced-osmolarity ORS solution (245 mmol/L). Intakes and outputs were measured every six hours until the cessation of diarrhoea. During maintenance therapy, stool output, intake of ORS solution, duration of diarrhoea, and the need for unscheduled administration of intravenous fluids were similar in the two treatment groups. The type of ORS solution that the patients received did not affect the mean serum sodium concentration at 24 hours after randomization and the relative risk of development of hyponatraemia. However, patients treated with reduced-osmolarity ORS solution had a significantly lower volume of vomiting and significantly higher urine output than those treated with standard WHO-ORS solution. Reduced-osmolarity ORS solution was as efficacious as standard WHO-ORS solution in the management of cholera patients. The results indicate that reduced-osmolarity ORS solution is also as safe as standard WHO-ORS solution. However, because of the limited sample size in the study, the results will have to be confirmed in trials, involving a larger number of patients. To compare the efficacy of a reduced osmolarity oral rehydration salts (ORS) solution (75 mmol/L of sodium [Na], 20 mmol/L of potassium [K], 65 mmol/L of chloride, 10 mmol/L of citrate, and 75 mmol/L of glucose; osmolarity, 245 mosm/L) with that of the standard World Health Organization (WHO) ORS solution.
                A multicenter, double-blind, randomized, controlled clinical trial conducted in children with acute diarrhea in 5 developing countries to measure mean stool output in the 24 hours after randomization, proportion of children who required unscheduled intravenous therapy, proportion of children who vomited in the first 24 hours, and diarrhea duration after randomization.
                A total of 675 children who ranged in age from 1 to 24 months and who had acute diarrhea and dehydration were enrolled in the trial; 341 were randomized to receive reduced osmolarity ORS solution, and 334 were randomized to receive the WHO ORS solution. The mean (SE) stool output (g/kg) in the first 24 hours (reduced osmolarity ORS solution vs WHO ORS solution = 114 [4] vs 125 [5]) and during the total study period (reduced osmolarity ORS solution vs WHO ORS solution = 320 [18] vs 331 [18]) were comparable. The proportion of children who vomited in the first 24 hours (reduced osmolarity ORS solution vs WHO ORS solution = 58% vs 62%) and the diarrhea duration in the 2 treatment groups, compared by log rank test, were similar. The proportion of children who required unscheduled intravenous therapy was significantly lower in children who received reduced osmolarity ORS solution (10%) as compared with those who received the WHO ORS solution (15%; odds ratio = 0.6, 95% confidence interval = 0.4-1.0). There was no significant difference in the incidence of hyponatremia (serum Na <130 mmol/L) at 24 hours between the 2 treatment groups (11% in reduced osmolarity ORS solution group vs 9% in the WHO ORS solution group; odds ratio = 1.3; 95% confidence interval = 0.8-2.2). The frequency of patients with serum Na <125 mmol/L at 24 hours was 13 of 341 (4%) in children who were treated with reduced osmolarity ORS solution versus 7 of 334 (2%) in children who received the WHO ORS solution.
                Treatment with reduced osmolarity ORS solution was associated with a 33% reduction in the need for unscheduled intravenous therapy and had no apparent effect on stool output and illness duration when compared with treatment with the standard WHO ORS solution. Children with acute diarrhea, therefore, may benefit from a reduced osmolarity ORS solution. The results of trials that examine the efficacy and safety of reduced osmolarity ORS solution in adult patients with cholera have to be taken into consideration before consensus on composition of oral rehydration formulation can be reached. To compare the safety and efficacy of an oral rehydration solution (ORS) containing 75 mmol/L of sodium and glucose each with the standard World Health Organization (WHO) ORS among Egyptian children with acute diarrhea.
                One hundred ninety boys, aged 1 to 24 months, who were admitted to the hospital with acute diarrhea and signs of dehydration were randomly assigned to receive either standard ORS (311 mmol/L) or a reduced osmolarity ORS (245 mmol/L). Intake and output were measured every 3 hours.
                In the group treated with reduced osmolarity ORS, the mean stool output during the rehydration phase was 36% lower (95% confidence interval, 1%, 100%) than in those treated with WHO ORS. The relative risk of vomiting during the rehydration phase was significantly lower in children treated with reduced osmolarity ORS (relative risk, 2.4; 95% confidence interval, 1.2, 4.8). During the maintenance phase, stool output, mean intake of food and ORS, duration of diarrhea, and weight gain were similar in the treatment groups. The relative risk of treatment failure (need for unscheduled administration of intravenous fluids) was significantly increased in children receiving standard WHO ORS (relative risk, 7.9; 95% confidence interval, 1.1, 60.9). The mean serum sodium concentration at 24 hours was significantly lower in children receiving the reduced osmolarity ORS solution (134 +/- 6 mEq/L) than in children receiving the standard WHO ORS (138 +/- 7 mEq/L) (p < 0.001). The relative risk of the development or worsening of hyponatremia was not increased in children given the reduced osmolarity ORS, and urine output was similar in the treatment groups.
                The reduced osmolarity ORS has beneficial effects on the clinical course of acute diarrhea in children by reducing stool output, and the proportion of children with vomiting during the rehydration phase, and by reducing the need for supplemental intravenous therapy. These results provide support for the use of a reduced osmolarity ORS in children with acute noncholera diarrhea. The clinical efficacy of a diluted oral rehydration salts (ORS) solution was compared in a pilot study with that of intravenous (i.v.) therapy and of standard World Health Organization (WHO)/United Nations Childrens Fund (UNICEF) ORS solution in children with acute diarrhea. Sixty-one boys aged 3 to 24 months, admitted to hospital with acute diarrhea and signs of dehydration, were randomly assigned to groups receiving standard ORS solution, diluted ORS solution, or i.v. therapy. In children treated with standard ORS solution and small amounts of plain water, the total fluid intake was 25-39% greater, the stool output was 58-77% greater (p < 0.01), and the duration of diarrhea was 30-55% greater than in the other treatment groups. Intake of plain water, taken separately or added to the ORS solution, was greater in children given diluted ORS solution (73 +/- 23 ml/kg) than in those given standard ORS solution (21 +/- 32 ml/kg) (p < 0.001). The mean serum sodium concentration increased by 2.2 mEq/L in children given standard ORS solution, whereas it decreased by 2.9 mEq/L in those given diluted ORS solution. This study shows that some children develop worsening diarrhea and increasing serum sodium concentrations when treated with standard ORS solution and given only small amounts of plain water. This is probably caused by the slight hypertonicity of standard ORS solution combined with transient partial glucose malabsorption. This can be avoided if water, breast milk, or another low-solute drink is given liberally during maintenance therapy with ORS solution, as recommended by the WHO. The effects of oral rehydration solution (ORS) with reduced osmolarity on children with acute watery diarrhoea are known, but little is known about the effects of such ORS on adults with cholera. We aimed to compare the efficacy and safety of an ORS with reduced osmolarity with that of standard WHO ORS in adults with cholera.
                We undertook a double-blind, controlled clinical trial in adults with severe cholera at the International Centre for Diarrhoeal Disease Research, Bangladesh. Our primary outcomes were mean stool output in the 24 h after randomisation, proportion of patients who needed unscheduled intravenous therapy, and proportion of patients with biochemical hyponatraemia 24 h after randomisation.
                147 patients received ORS with reduced osmolarity and 153 received standard WHO ORS. There was no significant difference between the two groups in terms of main outcome variables: mean initial 24 h and total stool output (reduced osmolarity vs standard WHO ORS 212 [SE 8] vs 207 [8] and 284 [13] vs 273 [13] g/kg respectively), duration of diarrhoea (46 [1.5] vs 43 [1.5]). The proportion of patients vomiting during the first 24 h and the proportion who received unscheduled intravenous infusion during the first 24 h was similar between groups. More patients on reduced osmolarity ORS than on standard WHO ORS developed hyponatraemia during the first 24 h, defined as serum sodium concentration below 130 mmol/L (29 of 142 vs 16 of 150; odds ratio 2.1 [95% CI 1.1-4.1]). However, all hyponatraemic patients in both groups were symptom-free and the proportion of patients with serum sodium concentration below 125 mmol/L was similar between groups.
                There was no difference in clinical outcome between cholera patients treated with reduced osmolarity ORS solution and those treated with standard WHO ORS. The risk of increased incidence of symptom-free hyponatraemia in patients with cholera treated with an ORS with reduced osmolarity should be further assessed by meta-analysis. The risk should be taken into account when choice of ORS is made in areas in which cholera is endemic. In developed countries, use of oral rehydration salts (ORS) solution with osmolarity lower than that of plasma has been recommended because of the risk of hypernatraemia. We compared the clinical efficacy of reduced-osmolarity ORS and standard ORS solutions in children with acute diarrhoea in four developing countries. 447 boys aged 1-24 months, admitted to hospitals in four countries with acute diarrhoea and signs of dehydration, were randomly assigned either standard ORS (311 mmol/L) or reduced-osmolarity ORS (224 mmol/L) solution. Total stool output was 39% greater (95% CI 11-75), total ORS intake 18% greater (3-33), and duration of diarrhoea 22% longer (2-45) in the standard ORS group than in the reduced-osmolarity ORS group. The risk of requiring intravenous infusion after completion of the initial oral rehydration was greater in children given standard ORS solution than in those given reduced-osmolarity ORS solution in three of the four countries (all-country relative risk 1.4 [0.9-2.4]). This relative risk was significantly increased only in non-breastfed children (2.0 [1.0-3.8], p < 0.05). In breastfed children, the relative risk of requiring intravenous infusion was not affected by the ORS solution (0.9 [0.4-2.0]). The mean sodium concentration 24 h after admission was significantly lower in the reduced-osmolarity ORS group than in the standard ORS group (135 [134-136] vs 138 [136-139] mmol/L, p < 0.01). Reduced-osmolarity ORS solution has beneficial effects on the clinical course of acute diarrhoea. Our findings support the use of reduced-osmolarity ORS solution in children with acute non-cholera diarrhoea in developing countries. Further studies are needed to find the best formulation and whether such a solution would be satisfactory for the treatment of cholera. Previously we reported that standard oral rehydration salts (ORS) solution is not as effective as a reduced-osmolarity glucose-based ORS for the treatment of children with acute noncholera diarrhoea: with standard ORS the diarrhoea lasts longer, stool output is greater, serum sodium is higher, and there is more need for supplemental intravenous infusion. We studied a reduced-osmolarity maltodextrin (MD)-based ORS to determine whether it had similar benefits, and also the effect of sugar malabsorption on the efficacy of standard and MD-based ORS. A total of 90 boys aged 3-24 months with acute noncholera diarrhoea and moderate dehydration were randomly assigned to either standard ORS (glucose 20 g/l, osmolarity 311 mmol/l) or MD-ORS (MD 50 g/l, osmolarity 227 mmol/l). There were no differences in treatment results. Some 46% of subjects had a high total stool output (> 300 g/kg), which was unrelated to the type of ORS given. High stool output was significantly associated with a longer duration of diarrhoea (33 vs. 15 hours; P < 0.001), a persistently elevated serum sodium (149 vs. 144 mmol/l at 24 h; P < 0.02), the need for intravenous infusion (11/41 vs. 0/48; P < 0.002), and an increase in faecal reducing substances (10.8 vs. 3.4 g/l at 24 h; P < 0.001). We conclude that some children given standard ORS develop osmotic diarrhoea owing to the combined effect of transient sugar malabsorption and slight hypertonicity of the ORS. Earlier studies show that this adverse outcome can largely be avoided when extra water is given in reduced-osmolarity glucose-based ORS. Reduced osmolarity has no benefit, however, when glucose is replaced by maltodextrin, probably because the sugars released by hydrolysis of MD, when malabsorbed, raise the intraluminal osmolarity to equal or exceed that of standard ORS. Thus, reduced-osmolarity glucose-based ORS is superior to both standard ORS and reduced-osmolarity solutions based on maltodextrin and probably other complex carbohydrates. Studies are in progress to define the optimal formulation of reduced-osmolarity glucose-based ORS. To evaluate the efficacy of a hypo-osmolar and a standard (World Health Organization) oral rehydration salt (ORS) solution in persistent diarrhoea, a randomized controlled clinical trial was conducted in 55 children. After a 1-day observation period the children were assigned to one of three solutions: standard ORS (WHO-ORS) (osmolality 311 mosmol/l), hypo-osmolar ORS containing L-alanine and glucose (osmolality 255 mosmol/l) and i.v. polyelectrolyte solutions (osmolality 293 mosmol/l) for ongoing replacement of stool loss for the next 4 days. Excellent acceptability of ORS (101-160 ml/kg body weight/day) by the children was observed. There were no significant differences in the total intake of solutions and food, and frequency of stools among the groups. Stool outputs were significantly less in infants receiving hypo-osmolar ORS than in those receiving WHO-ORS for 0-24 h (p = 0.04), 0-48 h (p = 0.01), 0-72 h (p = 0.04) and 0-96 h (p = 0.03). The results indicate a sufficient scope of ORS practice in persistent diarrhoea. Furthermore, we found that a hypo-osmolar ORS containing L-alanine and glucose is as efficacious as an iv solution and more effective than WHO-ORS for replacement of ongoing stool loss in persistent diarrhoea. In a controlled clinical trial conducted in 34 adults with severe cholera diarrhoea, the use of a relatively dilute oral rehydration salt (ORS) solution (sodium 67, potassium 20, chloride 66, citrate 7, glucose 89 mmol/l, osmolality 249 mOsmol/kg) caused a 29% (p=0.003) reduction in stool output over the first 24 h and a 37% (p=0.001) reduction over the first 48 h compared with 29 controls who received the hyperosmolar WHO/UNICEF ORS. No controls but 3 study-group patients had marked but asymptomatic hyponatraemia (sodium <125 mmol/l) at 24 h. Twenty-four % of controls and 12% of patients receiving the dilute ORS needed unscheduled intravenous therapy for recurrence of dehydration. The ORS intake was twice the 48 h stool volume in controls and 3 times in the study group. The test ORS with a reduced glucose and sodium concentration is more efficient than the WHO/UNICEF ORS in preserving net intestinal fluid balance in severe cholera.
In children admitted to hospital with diarrhoea, reduced osmolarity ORS when compared to WHO standard ORS is associated with fewer unscheduled intravenous fluid infusions, lower stool volume post randomization, and less vomiting. No additional risk of developing hyponatraemia when compared with WHO standard ORS was detected.