Seasonal water chemistry variability in the Pangani River basin, Tanzania.

The stable isotopes of δ18O, δ2H, and 87Sr/86Sr and dissolved major ions were used to assess spatial and seasonal water chemistry variability, chemical weathering, and hydrological cycle in the Pangani River Basin (PRB), Tanzania. Water in PRB was NaHCO3 type dominated by carbonate weathering with moderate total dissolved solids. Major ions varied greatly, increasing from upstream to downstream. In some stations, content of fluoride and sodium was higher than the recommended drinking water standards. Natural and anthropogenic factors contributed to the lowering rate of chemical weathering; the rate was lower than most of tropical rivers. The rate of weathering was higher in Precambrian than volcanic rocks. 87Sr/86Sr was lower than global average whereas concentration of strontium was higher than global average with mean annual flux of 0.13 × 106 mol year-1. Evaporation and altitude effects have caused enrichment of δ18O and δ2H in dry season and downstream of the river. Higher d-excess value than global average suggests that most of the stations were supplied by recycled moisture. Rainfall and groundwater were the major sources of surface flowing water in PRB; nevertheless, glacier from Mt. Kilimanjaro has insignificant contribution to the surface water. We recommend measures to be taken to reduce the level of fluoride and sodium before domestic use.

Risk factors, management and outcomes of adverse drug reactions in adult patients on antiretrovirals at Kenyatta National Hospital, Nairobi.

BACKGROUND: Antiretrovirals have been associated with serious adverse drug reactions. Several factors have been suggested as independent risk factors for their development. Identification of these factors may help in prevention and management of the adverse drug reactions. OBJECTIVE: To describe the factors associated with adverse drug reactions, their management, and the clinical outcomes. DESIGN: A retrospective cohort study. SETTING: Kenyatta National Hospital, Comprehensive Care Centre. SUBJECTS: Adult patients receiving antiretrovirals from 2003 to 2006. MAIN OUTCOME MEASURES: The primary outcomes were the risk-factors, interventions and outcomes of documented adverse drug reaction after exposure to antiretrovirals. RESULTS: Systematic random sampling was used to pick 350 patients' files. The risk factors for experiencing at least one adverse drug reaction were: having a baseline CD4 count less than 123 (odds ratio [OR] = 1.82, 95% confidence interval [CI: 1.18 to 2.79; p = 0.006); treatment with antiretrovirals for more than 32 months (OR = 1.76, CI: 1.15 to 2.71; p = 0.010), using didanosine containing regimens (OR = 3.7, CI: 1.40 to 9.70; p = 0.008) or being on stavudine containing regimens (OR = 4.4, CI: 2.53 to 7.71; p = 0.001). The most common intervention was addition of a non-antiretroviral while 41% of events resulted in a change of anti-retroviral therapy. CONCLUSIONS: Current standard regimens in resource-limited countries are associated with an increased risk of adverse drug reactions. Almost half of adverse reactions are managed by addition of a non-anti-retroviral drug alone but 41% necessitated a change of anti-retrovirals.

Spatial clustering and epidemiological aspects of visceral leishmaniasis in two endemic villages, Baringo District, Kenya.

Visceral leishmaniasis (VL) seroprevalence in Kenya is unknown because of the lack of a practical and accurate diagnostic test or surveillance system. A novel serological assay was used to estimate the seroprevalence of Leishmania-specific antibodies, and Global Information System and spatial clustering techniques were applied to study the presence of spatial clusters in Parkarin and Loboi villages in Baringo District in 2001. VL seroprevalences were 52.5% in Parkarin and 16.9% in Loboi. Significant associations among seropositivity and house construction, age, and proximity to domestic animal enclosures were found. A significant spatial cluster of VL was found in Loboi. The spatial distribution of cases in the two villages was different with respect to risk factors, such as presence of domestic animals. This study suggests that disease control efforts could be focused on elimination of sand fly habitat, placement of domestic animal enclosures, and targeted use of insecticides.

A phase II dose-increasing study of sitamaquine for the treatment of visceral leishmaniasis in Kenya.

Sitamaquine (WR6026) is an 8-aminoquinoline in development for the oral treatment of visceral leishmaniasis (VL). This was an open-label, dose-increasing study to determine the dose-response and safety profile for sitamaquine in Kenyan patients with VL caused by Leishmania donovani. Patients (mean age 15.9 [range = 5-47] years) received sitamaquine daily for 28 days at one of four doses: 1.75 (n = 12), 2.0 (n = 61), 2.5 (n = 12), or 3.0 (n = 12) mg/kg/day. The primary efficacy outcome was cure (absence of parasites on splenic aspirate) in the intent-to-treat population at day 180. Cure was achieved in 79 (83%) of 95 patients overall, and in 11 (92%) of 12, 49 (80%) of 61, 9 (82%) of 11, and 10 (91%) of 11 patients at sitamaquine doses of 1.75, 2.0, 2.5, or 3.0 mg/kg/day, respectively. The most frequent adverse events during active treatment were abdominal pain (12 [12%] of 97) and headache (11 [11%] of 97), and one patient in each of the 2.5 mg/kg/day and 3.0 mg/kg/day dose groups had a severe renal adverse event. The effects of sitamaquine on the kidney need further investigation. Sitamaquine was efficacious and generally well tolerated in Kenyan patients with VL.

Comparison of safety of glucose oral rehydration solution and maize oral rehydration therapy for home management of diarrhoea in Kenya.

Safety margins and variability in the composition of glucose and maize-based oral rehydration therapy (ORT) prepared by mothers in a rural district of Western Kenya, are reported here. In a 2-year longitudinal field study, packets containing glucose ORS and a home solution made with maize and table salts, were provided to the mothers of 6180 children in Kakamega District in two separate sub-locations. Experienced and trained field workers supported by community registered nurses provided training for the preparation and use of ORT during weekly visits to every household. On four occasions separated by 4-6 months, a 5 per cent random sampling was done of the home-prepared solutions actually used for the treatment of children with diarrhoea. The water used for preparing ORT was also sampled. Samples of 174 glucose-based ORT, 148 maize-salt ORT, and 201 samples of water were analysed. Only 2 per cent of the maize-based ORT were above 120 meq/1 sodium (i.e., the safe range of sodium concentration) compared to 17.8 per cent for glucose solutions (p < 0.001). Home water samples contained substantial amounts of salt, which could unpredictably affect the final composition of the ORT solutions. We conclude that maize-salt ORT had a better margin of safety than glucose-based ORS.

Maize-salt solution in the treatment of diarrhoea.

In a block-randomized trial we compared the efficacy of citrate-containing glucose electrolyte solution (GES) versus maize-salt solution (MSS) in the treatment of children with mild and moderate diarrhoeal dehydration and acidosis. One hundred and fifteen children aged 3-59 months were entered in the study; 56 received GES and 59 MSS. Fifty-one (91%) of the 56 children given GES and 52 (88%) of the 59 children given MSS were successfully rehydrated with improvement in metabolic acidosis within 24 h. Initial hypokalemia in children treated with maize-salt solution was not corrected during the first 24 h of therapy. The children were, however, clinically asymptomatic after treatment. Carefully prepared maize-salt solution may be used successfully in mild and moderate dehydration in the home, as an alternative to the preferred glucose electrolyte formula.

Oral rehydration therapy and social marketing in rural Kenya.

In just a few years, oral rehydration therapy (ORT) has become the standard treatment to reduce infant diarrhoeal disease mortality in the developing world. The paper describes an ORT intervention campaign in a rural area in Western Kenya (Kakamega District). After about a year of careful preparation, the campaign was launched in January 1986 and compared the use of a value-added product (flavoured sachets) sold through private outlets in addition to primary care distribution of an unflavoured sachet in an experimental cell (Bukura Division). In a control cell (Novakholo Division), only unflavoured sachets were distributed free of charge through primary health care facilities. Using local perceptions of diarrhoeal disease management, the campaign in the experimental cell was carefully designed and mass communication techniques employed and adapted accordingly. Outcome assessments of the campaign, which lasted until March 1987, included the overall ORT utilisation over time. Changes in perceptions towards diarrhoeal disease management, direct assessments of mixing a 'safe and effective' solution accurately and other relevant process parameters were evaluated. Comparing several recent ORT intervention projects, the paper concludes that a combination of a commercial approach and mass communication techniques can further ORS use. If a proper incentive system for shopkeepers is installed and message design and ORS product are fully tailored to the perception and preferences of the target population, the commercial availability of ORS will create an extra demand of the product. However, this will not replace distribution of ORS salts delivered free of charge through primary care sources.

Cereal based oral rehydration solutions.

A total of 257 boys (age range 4-55 months), who had acute diarrhoea with moderate to severe dehydration, were randomly assigned to treatment with either the World Health Organisation/United Nations Childrens Fund (WHO/Unicef) recommended oral rehydration solution or cereal based oral rehydration solution made either of maize, millet, sorghum, or rice. After the initial rehydration was achieved patients were offered traditional weaning foods. Treatment with oral rehydration solution continued until diarrhoea stopped. Accurate intake and output was maintained throughout the study period. Efficacy of the treatment was compared between the different treatment groups in terms of intake of the solution, stool output, duration of diarrhoea after admission, and weight gain after 24, 48, and 72 hours, and after resolution of diarrhoea. Results suggest that all the cereal based solutions were as effective as glucose based standard oral rehydration solution in the treatment of diarrhoea.

Aetiology of diarrhoea in malnourished children at Kenyatta National Hospital.

PIP: 3 groups of children aged 0-5 years were studied at Kenyatta National Hospital between September 1983 and September 1984 to determine the incidence of enteric agents causing diarrhea in infants and children. The 1st group consisted of children with diarrhea alone, the 2nd group had diarrhea and kwashiorkor, and the 3rd had diarrhea and marasmus. Diarrhea occurring alone peaked in the 0-5 month age group; diarrhea and marasmus peaked in the 6-11 month group, and diarrhea and kwashiorkor, the 6-17 month group. Isolation rates of enteric agents (Campylobacter, Shigella, Salmonella, Rotavirus) for the 3 groups were not significantly different; however E. coli was isolated with a higher frequency from children who had diarrhea with marasmus. The most common mixed infection was that of E. coli and Rotavirus, occurring more often in children with marasmus. Most children had a history of diarrhea for 3-5 days duration. Among agents isolated from cases of more than 8 days duration, Campylobacter was most common, and was only isolated from malnourished children. Results indicate that duration of diarrhea before admission was longer in kwashiorkor or marasmic children than children with diarrhea alone. Treatment for diarrhea in all cases should be similar.^ieng