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Biomedical subjects

M K Bhan

Publications and source records attributed to M K Bhan.

At least 73 records · Page 4Linked to original sources
PubMed1996

Efficacy of antimicrobial treatment in non-dysenteric persistent diarrhoea in a community setting.

OBJECTIVES: To determine the efficacy of antimicrobial treatment in non-dysenteric persistent diarrhoea in a community setting. METHODS: In this double-blind field trial, 156 children aged 4-36 months with persistent diarrhoea not associated with Giardia lamblia infestation seeking treatment in a community outpatient clinic, were randomized to receive a combination of nalidixic acid and metronidazole, metronidazole alone, or placebo for 7 days. RESULTS: In comparison with placebo, metronidazole treatment did not result in a significant reduction in the mean post-enrollment diarrhoeal duration and stool frequency, increase in the proportion of patients recovered by days 3, 5 and 7 of treatment, and increase in weight gain at days 7 and 14. Comparing the combination of nalidixic acid and metronidazole with metronidazole alone, 17.5% more children treated with the combination recovered by day 3 of treatment (p = 0.08) and the mean stool frequency ascertained on day 7 for the previous 24 h was 26.8% less in them (p = 0.05). The weight gains at days 7 and 14 were similar in the two groups. CONCLUSIONS: These findings indicate that metronidazole offers no therapeutic benefit in persistent diarrhoea not associated with Giardia lamblia and nalidixic acid has only a modest clinical benefit, which is not substantial enough to warrant its routine use.

Anti-Infective Agents↗
PubMed1996

Increased diarrhoeal and respiratory morbidity in association with zinc deficiency--a preliminary report.

Plasma zinc levels, in a cohort of 116 children aged 12-59 months recently recovered from an episode of acute diarrhoea attending a community health clinic in an urban slum, were related to diarrhoeal and respiratory morbidity in the 3 month period following recovery. Children with low plasma zinc levels (< 60 micrograms dl-1) spent a significantly greater number of days with watery diarrhoea (rate ratio 1.69 (95% confidence intervals 1.03-2.78)), diarrhoea associated with fever (rate ratio 1.88 (95% confidence intervals 1.05-3.34)), and acute lower respiratory tract infections (rate ratio 2.69 (95% confidence intervals 1.64-4.38)).

Child, Preschool↗
PubMed1996

Identification and characterization of CS20, a new putative colonization factor of enterotoxigenic Escherichia coli.

An enterotoxigenic Escherichia coli (ETEC) strain producing a previously undescribed putative colonization factor was isolated from a child with diarrhea in India. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of bacterial heat extracts revealed a polypeptide band of 20.8 kDa when the bacteria were grown at 37 degrees C which was absent after growth at 22 degrees C. A specific rabbit antiserum raised against the purified 20.8-kDa protein bound specifically to the fimbriae, as shown by immunoelectron microscopy, and inhibited bacterial adhesion to tissue-cultured Caco-2 cells. Transformation with a recombinant plasmid harboring the cfaD gene, which encodes a positive regulator for several ETEC fimbriae, induced hyperexpression of the 20.8-kDa fimbrial subunit and a substantial increase in the proportion of bacterial cells that were fimbriated. The N-terminal amino acid sequence of the polypeptide showed 65 and 60% identity to the PCFO20 and 987P fimbriae of human and porcine ETEC, respectively. We propose the term CS20 for this new putative colonization factor of human ETEC.

Adhesins, Bacterial↗
PubMed1996

Unusual diversity of human rotavirus G and P genotypes in India.

Between April and December 1993, we determined P and G genotypes of group A rotavirus strains obtained from children admitted to diarrhea treatment centers in five Indian cities. From a total of 63 rotavirus-positive specimens, we identified 10 different strains with five different G genotypes and four distinct P types by using reverse transcription-PCR. The common worldwide strains G1P8, G2P4, G3P8, and G4P8 were underrepresented among Indian children (33%), whereas strains of P type 6 (G1P6, G2P6, G3P6, G4P6, and G9P6), which primarily infect asymptomatic newborns but are rare in children with diarrhea were common in India (43%). Of these, G9P6, a strain not previously reported to be found in children with diarrhea, was the most prevalent (22%). Eleven percent of the strains were nontypeable, and another 11% of the specimens had mixed infections. Using digoxigenin-labeled, genotype-specific hybridization probes, we confirmed all G9 strains and mixed infections tested and identified three nontypeable strains (one G9 and two P8). The epidemiological significance of G9 rotavirus strains, if confirmed in other settings, may have important implications for vaccine development.

Base Sequence↗
PubMed1996

Epidemiology & management of persistent diarrhoea in children of developing countries.

Diarrhoea that begins acutely but lasts longer than two weeks is defined to be persistent. Revised estimates in developing countries including India showed that acute diarrhoea accounts for 35 per cent, dysentery 20 per cent and non-dysenteric persistent diarrhoea (PD) for 45 per cent of total diarrhoeal deaths. PD also often changes marginal malnutrition to more severe forms. Factors that increase the risk of acute diarrhoea becoming persistent have been identified in India and other developing countries. These include antecedent malnutrition, micronutrient deficiency particularly for zinc and vitamin A, transient impairment in cell mediated immunity, infection with entero aggregative Escherichia coli and cryptosporidium, sequential infection with different pathogens and lack of exclusive breast feeding during the initial four months of life particularly use of bovine milk. Several issues regarding the management of persistent diarrhoea in hospitalized children in India have been resolved. Diets providing modest amounts of milk mixed with cereals are well tolerated. In those who fail on such diets providing carbohydrate as a mixture of cereals and glucose or sucrose hasten recovery. The role of antimicrobial agents and individual micronutrients in PD is currently being investigated. A management algorithm appropriate for India and other developing countries has been developed and found to substantially reduce case fatality in hospital settings to about 2-3 per cent. Recent epidemiological and clinical research related to persistent diarrhoea is also reviewed.

Animals↗
PubMed1996

Efficacy of milk-based diets in persistent diarrhea: a randomized, controlled trial.

OBJECTIVE: Previous studies have shown increased stool output when children with persistent diarrhea (PD) received milk as the predominant source of nutrition. METHODS: We evaluated the efficacy of milk given in modest amounts as a part of a mixed diet in children with PD. One hundred sixteen children 3 to 24 months of age with diarrhea for between 14 days and 12 weeks were allocated to milk-based (n = 60) or milk-free (n = 56) cereal dietary regimens. The two diets were isocaloric (86.9 calories/100 g for < or = 9 months; 95.6 cal/100 g for > 9 months) consisting of puffed rice cereal, sugar, and oil differing in only their source of protein, which was either milk or egg white, respectively. An average of 30% of the calories were constituted by milk in the milk-cereal diet. Both diets were offered at the rate of 150 kcal/kg per day. Children receiving milk-cereal consumed an average of 1.9 g/kg lactose per day. RESULTS: The baseline characteristics in the two groups were similar. Comparable amounts of diet were consumed in both groups. The milk-cereal group did not have higher median (range) stool output (g/kg/h) compared with the milk-free group during a 0- to 48-hour (milk-cereal, 1.7 [0.2 to 8.7]; milk-free, 1.5 [0.1 to 6.6]) or 0- to 120-hour (milk-cereal, 1.6 [0.4 to 7.2]; milk-free, 1.3 [0.1 to 7.6]) period. The percentage of weight gain was similar in the two groups, and there were no significant differences in the duration of diarrhea. Overall, 23 children had treatment failures, 10 (17%) in the milk-cereal and 13 (23.6%) in the milk-free groups. CONCLUSIONS: Our findings suggest that modest intakes of milk are well tolerated as a part of mixed diet during PD.

Animals↗
PubMed1996

Effect of zinc supplementation on observed activity in low socioeconomic Indian preschool children.

OBJECTIVES: To investigate whether supplementation of zinc in preschool children is associated with improvement in observed activity levels. METHODS: On 2 consecutive days, we performed 5-hour observations with momentary time sampling (instant activity every 10 minutes) in children selected from an ongoing double-blind, randomized trial of zinc supplementation. The study was conducted in Kalkaji, a low-socioeconomic urban population of New Delhi with high diarrheal incidence and rates of malnutrition. A total of 93 children (48 zinc and 45 control) 12 to 23 months of age from an ongoing community-based, randomized, controlled trial received supplements for at least 1 month before study; 71% had received supplementation for more than 120 days. Zinc gluconate (10 mg of elemental zinc) was given daily, with both zinc and control groups receiving vitamins A, B1, B2, B6, D3, and E and niacinamide in addition. RESULTS: Outcomes were percentages of time spent in each of five activity levels and two groups representing high and low movement and overall rating by two activity scores. Children in the zinc group spent 72% more time performing activities in the high-movement group. Among the zinc-supplemented children, the activity rating by the children's activity rating score was 12% higher and by the energy expenditure score was 8.3% higher than in the control group. CONCLUSIONS: In conclusion, zinc supplementation, given along with selected vitamins, was associated with significantly greater activity levels in children. The relationship between the activity increase and locomotor development needs to be investigated, as do the long-term implications of zinc supplementation in terms of developmental status and school performance.

Double-Blind Method↗
PubMed1995

Zinc supplementation in young children with acute diarrhea in India.

BACKGROUND: In developing countries the duration and severity of diarrheal illnesses are greatest among infants and young children with malnutrition and impaired immune status, both factors that may be associated with zinc deficiency. In children with severe zinc deficiency, diarrhea is common and responds quickly to zinc supplementation. METHODS: To evaluate the effects of daily supplementation with 20 mg of elemental zinc on the duration and severity of acute diarrhea, we conducted a double-blind, randomized, controlled trial involving 937 children, 6 to 35 months of age, in New Delhi, India. All the children also received oral rehydration therapy and vitamin supplements. RESULTS: Among the children who received zinc supplementation, there was a 23 percent reduction (95 percent confidence interval, 12 percent to 32 percent) in the risk of continued diarrhea. Estimates of the likelihood of recovery according to the day of zinc supplementation revealed a reduction of 7 percent (95 percent confidence interval, -9 percent to +22 percent) in the risk of continued diarrhea during days 1 through 3 and a reduction of 38 percent (95 percent confidence interval, 27 percent to 48 percent) after day 3. When zinc supplementation was initiated within three days of the onset of diarrhea, there was a 39 percent reduction (95 percent confidence interval, 7 percent to 61 percent) in the proportion of episodes lasting more than seven days. In the zinc-supplementation group there was a decrease of 39 percent (95 percent confidence interval, 6 percent to 70 percent) in the mean number of watery stools per day (P = 0.02) and a decrease of 21 percent (95 percent confidence interval, 10 percent to 31 percent) in the number of days with watery diarrhea. The reductions in the duration and severity of diarrhea were greater in children with stunted growth than in those with normal growth. CONCLUSION: For infants and young children with acute diarrhea, zinc supplementation results in clinically important reductions in the duration and severity of diarrhea.

Acute Disease↗
PubMed1995

Safety of ciprofloxacin therapy in children: magnetic resonance images, body fluid levels of fluoride and linear growth.

We evaluated the safety of ciprofloxacin administered in a dose of 15-25 mg/kg for 9-16 days, in a case series of 58 children who were between 8 months and 13 years of age. No arthropathy was observed during therapy and follow-up. Blinded evaluation of 22 pairs of nuclear magnetic resonance scans obtained before and between day 10 and 15 of therapy did not reveal any cartilage damage. After the first dose of ciprofloxacin (10 mg/kg), serum fluoride levels increased at 12 h in 15 of 19 (79%) patients; 24-h urinary fluoride excretion was higher on day 7 compared with basal values in 16 of 18 (88.9%) patients. Height z scores of 53 patients at a mean of 22.5 months of follow-up were not significantly different from basal scores (p = 0.12). In conclusion, ciprofloxacin may be recommended for use in children for short duration when effective alternative antibacterials are unavailable. However, there is a need for further studies to evaluate the tissue accumulation of fluoride and its potential to cause toxic effects.

Adolescent↗
PubMed1995

Antibodies raised against the outer membrane protein interrupt adherence of enteroaggregative Escherichia coli.

Enteroaggregative Escherichia coli (EAggEC) is a distinct category of diarrheal pathogen implicated as the cause of persistent diarrhea. The pathogen exhibits a characteristic "stacked-brick" pattern of aggregation when incubated with HEp-2 cells. The outer membrane protein (OMP) profile of a prototype EAggEC strain (F03) reflected the presence of one major 30-kDa protein. The OMP is expressed in the presence of the 60-MDa plasmid that the strain harbors. Antibodies were raised against the OMP by injecting the protein into a rabbit. The manifestation of an adherence phenotype on HEp-2 cells was observed for F03 and other strains that express OMP in the presence and absence of anti-OMP serum. Clumps of bacteria forming an aggregative pattern were observed in the HEp-2 cell assay in the absence of OMP antibodies, whereas a few bacteria attached to the cells in the presence of OMP antibodies. Mannose-resistant hemagglutination of human erythrocytes observed in the presence of EAggEC strains was inhibited in the presence of anti-OMP serum. Sequence analysis of a peptide generated by protease digestion of OMP exhibited 90% homology to a peptide of flagellin protein encoded by the hag gene of Serratia marcescens. Immunolabeling of the outer membrane by colloidal gold confirmed the protein to be an OMP. Our results suggest that the OMP of EAggEC have common antigenic properties. Antibodies raised against the protein can prevent adherence in vitro and could potentially interrupt the natural disease.

Amino Acid Sequence↗
PubMed1994

Impact of massive dose of vitamin A given to preschool children with acute diarrhoea on subsequent respiratory and diarrhoeal morbidity.

OBJECTIVE: To assess the impact of vitamin A supplementation on morbidity from acute respiratory tract infections and diarrhoea. DESIGN: Double blind randomised placebo controlled field trial. SETTING: An urban slum area in New Delhi, India. SUBJECTS: 900 children aged 12-60 months attending a local health facility for acute diarrhoea of less than seven days' duration randomly allocated to receive vitamin A 200,000 IU or placebo. MAIN OUTCOME MEASURES: Incidence and prevalence of acute lower respiratory tract infections and diarrhoea during the 90 days after termination of the enrolment diarrhoeal episode measured by twice weekly household surveillance. RESULTS: The incidence (relative risk 1.07; 95% confidence interval 0.92 to 1.26) and average number of days spent with acute lower respiratory tract infections were similar in the vitamin A supplementation and placebo groups. Among children aged 23 months or less there was a significant reduction in the incidence of measles (relative risk 0.06; 95% confidence interval 0.01 to 0.48). The incidence of diarrhoea was also similar (relative risk 0.95; 0.86 to 1.05) in the two groups. There was a 36% reduction in the mean daily prevalence of diarrhoea associated with fever in the vitamin A supplemented children older than 23 months. CONCLUSIONS: Results were consistent with a lack of impact on acute lower respiratory tract related mortality after vitamin A supplementation noted in other trials and a possible reduction in the severity of diarrhoea.

Acute Disease↗
PubMed1994

High prevalence of rotavirus infection among neonates born at hospitals in Delhi, India: predisposition of newborns for infection with unusual rotavirus.

Although rotavirus is the most common cause of diarrhea in children older than 3 months of age, neonatal infections, which are asymptomatic, have rarely been surveyed and have been identified in only a few discrete nosocomial outbreaks. After such a nosocomial outbreak of rotavirus infection among newborns at a hospital in Delhi, we screened infants born at five other nurseries in the immediate area to assess the prevalence of neonatal infections and to determine whether the unique neonatal rotavirus strain, 116E, previously identified in Delhi, was present in other settings. Infection was documented in 43 to 78% of hospitalized infants between 4 and 6 days of life born at five of the six hospitals. Infection with strains related to 116E were the most common, but other unusual strains and no strains common in the community were detected. In addition a shift in genotype was observed among specimens collected from two of these hospitals during a 2-year period. Our observation that neonatal rotavirus infections are more common than recognized previously would encourage the administration of rotavirus vaccines during the newborn period and suggests that the low efficacy of vaccines observed during trials in developing countries may be caused by early natural exposure of infants before immunization. The extraordinary predisposition of neonates for unusual rotavirus strains not commonly found in the community should encourage others to screen neonates for this infection, characterize the strains more fully and attempt to understand at a molecular level the unique relationship between the infecting strain type and the age of the host.

Feces↗
PubMed1994

Plasmid-coded DNA fragment developed as a specific gene probe for the identification of enteroaggregative Escherichia coli.

Enteroaggregative Escherichia coli (EAggEC) is a recently discovered diarrhoeal pathogen implicated as a cause of persistent diarrhoea in children. EAggEC strains exhibit a characteristic pattern of adherence when incubated with HEp-2 cells. Because of the difficulty in identifying this group of bacteria, the epidemiological significance of this pathogen as a diarrhoeal agent has not been fully realised. A gene probe was developed from the 60-MDa plasmid associated with EAggEC strains that encodes the genes for adherence and fimbriae. The sensitivity of the gene probe was 93% and the specificity 98% for detecting EAggEC isolates and is potentially useful for diagnostic and epidemiological studies.

Bacterial Adhesion↗
PubMed1994

Genotypic and phenotypic identification of coli surface antigen 6-positive enterotoxigenic Escherichia coli.

A polynucleotide probe comprising the gene encoding a major structural subunit protein of coli surface antigen 6 (CS6) of enterotoxigenic Escherichia coli (ETEC) was developed. Eighty-nine ETEC isolates were examined in parallel with the probe in a colony hybridization assay and in a recently developed polyclonal-antibody-based inhibition enzyme-linked immunosorbent assay (ELISA). The two assays showed a high level of concordance in the detection of CS6-positive ETEC (kappa = 0.84, P < 0.00001). Thus, 36 of the 89 ETEC isolates were identified as CS6-positive by both assays. Six strains that were negative for other colonization factor antigens were positive with the CS6 probe but negative in the ELISA, suggesting lack of surface CS6 expression in these strains. One strain was probe negative but positive in the ELISA, while the remaining 46 strains were negative in both assays. The phenotypic and genotypic assays will prove useful in vaccine-oriented studies of ETEC disease.

Antigens, Bacterial↗
PubMed1994

Characterization of rotavirus strains from newborns in New Delhi, India.

Between 1986 and 1993, 72% of rotavirus strains isolated from newborns at five hospitals in New Delhi, India, had long electropherotypes, subgroup II VP6 antigens, and G and P genotypes (G9P11) identical to those of prototype strain 116E. A novel strain with a G9P6 genotype, representing 13% of the isolates, was identified. These results demonstrate that G9P11 and G9P6 rotavirus strains are common in nurseries in New Delhi.

Base Sequence↗
PubMed1994

Clinical trials of improved oral rehydration salt formulations: a review.

Reviewed are all the published clinical trials of glycine-based oral rehydration salts (ORS), L-alanine-based ORS, L-glutamine-based ORS, maltodextrin-based ORS, and rice-based ORS, as well as the results of several recently completed, but unpublished, studies of these formulations that were supported by WHO. All experimental ORS formulations contained the same concentrations of salts as citrate-based WHO-ORS; all trials were randomized comparisons with WHO-ORS, and all except those with rice-based ORS were double-blind studies. The rate of stool loss and, less frequently, the duration of diarrhoea were used as indicators of clinical performance to compare ORS formulations. The following conclusions were reached concerning the efficacy and use of modified ORS formulations. Rice-based ORS (50 g/l) is superior to WHO-ORS for patients with cholera, and for such patients it can be recommended in any situation where its preparation and use are practical. Rice-based (50 g/l) and WHO-ORS solutions are equally effective for treating children with acute non-cholera diarrhoea, when feeding is resumed promptly following initial rehydration, as has been consistently recommended by WHO. Since rice-based ORS is not superior to WHO-ORS for such children, there is no apparent reason to advise a change from glucose to pre-cooked rice in the recommended formulation for WHO-ORS. Maltodextrin-based ORS formulations (50 g/l) and WHO-ORS appear to be equally effective for treating children with acute non-cholera diarrhoea; there is no reason to advise a change from glucose to maltodextrin in the recommended formulation for WHO-ORS. Amino-acid-containing ORS formulations are not recommended for either non-cholera or cholera diarrhoea, since they are more costly and have no clinical advantage over WHO-ORS for children with acute non-cholera diarrhoea or over rice-based ORS for persons with cholera.

Child, Preschool↗