Efficacy and safety of oral rehydration solution with reduced osmolarity in adults with cholera: a randomised double-blind clinical trial. CHOICE study group. Controlled trial of hypo-osmalar versus World Health Organization oral rehydration solution. Standard WHO-ORS versus reduced-osmolarity ORS in the management of cholera patients. Reduced osmolarity oral rehydration salt in Cholera. Evaluation of oral hypo-osmolar glucose-based and rice-based oral rehydration solutions in the treatment of cholera in children. Efficacy of a packaged rice oral rehydration solution among children with cholera and cholera-like illness. Attenuated live cholera vaccine strain CVD 103-HgR elicits significantly higher serum vibriocidal antibody titers in persons of blood group O.
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. To compare the safety and efficacy of a hyposmolar oral rehydration solution (H-ORS) (245 mmol/liter) with the World Health Organization oral rehydration solution (WHO ORS) in cholera and acute non-cholera diarrhea.
                Controlled clinical trial.
                Diarrhea training and treatment unit.
                Thirty-five culture proven cholera and 135 acute non-cholera diarrheal patients randomly received H-ORS or WHO-ORS. Intake and output were measured every 4 hours.
                Analysis of the total cases revealed rehydration phase (p=0.048, 95% CI 0.64-0.99) and overall (p=0.046, 95% CI 0.70-0.99) frequency of stools to be significantly less in the H-ORS group. In the severely malnourished, the rehydration phase (p=0.032, 95% CI 0.55-97), maintenance phase (p=0.035, 95% CI 0.51-0.97) and overall (p=0.011; 0.95% CI 0.55-0.93) stool frequency were significantly decreased in the H-ORS group. The amount of ORS consumed in the maintenance phase of the cholera cases was significantly (p=0.04, 95% CI 0.44-0.98) less in the H-ORS group. All other parameters, despite showing a decreasing trend, were statistically comparable in the cholera, non-cholera and total cases. The amount of intravenous fluid needed was significantly more in the noncholera and total cases on H-ORS. In the non-breastfed cases, under two years of age, the total duration of diarrhea was significantly decreased (p=0.03; 95% CI 11.07-11.45) but the need for intravenous fluids significantly increased (p=0.02; 95% CI 109.8-112.1) in the H-ORS group. The proportion of children vomiting, the weight gain, urine passed in 24 hours, serum sodium, caloric intake and failure rate were comparable.
                H-ORS is as safe and effective as the WHO-ORS and may have some additional benefits in malnourished children. 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. 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 a randomized controlled clinical trial, the efficacy of a low-sodium low-glucose oral rehydration solution (ORS) and a low-sodium rice-based ORS was compared with standard WHO glucose ORS in the treatment of severe cholera in children aged 2-10y. In total, 120 children were evaluated for the study, of whom 58 patients were positive for Vibrio cholerae and were included in the study. Of these 58 cases, 19 received rice-based hypo-osmolar ORS, 20 received WHO-ORS and 19 received glucose-based hypo-osmolar ORS. The clinical characteristics (age, preadmission duration of diarrhoea, frequency of stool before admission, incidence of vomiting, body weight and volume of initial fluid requirement) were comparable in the three treatment groups. All patients received tetracycline in a dose of 50 mg/kg/d of body weight in 4 divided doses for 3 d.
                Patients who received rice-based hypo-osmolar ORS had subsequently reduced (p < 0.05) stool output, ORS consumption and diarrhoea duration than the patients who received either WHO-ORS or glucose-based hypo-osmolar ORS. In past studies, patients with cholera and cholera-like diarrhoea treated with rice oral rehydration solution (ORS) had lower purging rates and a shorter illness duration. We evaluated a new packet form of rice ORS (CeraLyte-90) in 167 boys aged 5 to 15 y, with acute, dehydrating cholera and cholera-like diarrhoea in Bangladesh. The patients were randomized to receive either CeraLyte-90 (n = 85) or glucose ORS (n = 82) and were given early feeding and early antibiotics. The efficacy of the two solutions was compared for stool output during the first 8 h, the first 24 h, and total output, duration of diarrhoea, hematocrit, serum electrolytes and requirement for unscheduled intravenous fluids. The clinical and laboratory characteristics of the two groups were comparable on admission, and most of the patients had cholera (88% and 84% in the CeraLyte and glucose groups, respectively). The mean (+/- SE) stool output was 20% less in the rice ORS group during the first 8 h of treatment (86.2+/-6.6 ml/Kg vs 108.8+/-7.9 ml/Kg, p < 0.05), but the outputs during the other time periods were similar in the two groups, although children in the rice ORS group had slightly more vomiting on day one (p < 0.05). The mean serum electrolyte concentrations in both groups of children remained within normal range.
                The study documents the safety and efficacy of the new, packaged rice ORS. Persons of blood group O are at increased risk of developing cholera gravis. In a randomized, placebo-controlled, double-blind safety-immunogenicity trial of live oral cholera vaccine CVD 103-HgR in 5- to 9-year-old Chilean children, vibriocidal antibody seroconversion (74% overall) did not differ by blood group. However, the reciprocal geometric mean titer (GMT) in blood group O vaccines (GMT = 486) was higher than that in non-O vaccines (GMT = 179) (P < 0.02).
In people with cholera, ORS ≤ 270 is associated with biochemical hyponatraemia when compared with ORS ≥ 310, but there are no differences in terms of other outcomes. Although this risk does not appear to be associated with any serious consequences, the total patient experience in existing trials is small. Under wider practice conditions, especially where patient monitoring is difficult, caution is warranted.