Epidemiology of Injuries at a Tertiary Care Center in Malawi

Background  Injury surveillance is an ongoing process required for primary, secondary, and tertiary injury prevention. In Malawi, hospital-based injury data are not available. Methods  From February to June 2008 we collected data on injured patients presenting to Kamuzu Central Hospital in Lilongwe, Malawi. The sample (n = 1,474) was predominantly male (75.7%), and age distribution was bimodal (peak age groups <5 years and 26–30 years). Road-traffic injury (RTI) was the most common reason for treatment (43.4%), followed by assault (24.0%), which was more common than expected. The most common injuries were lacerations, contusions, and abrasions. We observed both gender- and age-specific patterns in injury mechanism: Injured females were more likely than injured males to have suffered an injury as a passenger in a car or on a bicycle, or to have suffered from falls, foreign bodies, and burns; injured males were more likely than injured females to have suffered an injury as an automobile driver or bicyclist, or from an assault. Falls, burns, and foreign bodies affected younger victims, whereas bicyclists, automobile drivers, and motorcycle operators were generally older persons. Results  The hospital admission rate was 26.8%. Most patients arrived by private vehicle (43.8%), which was also the fastest means of transportation. There were 25 mass casualties leading to 102 admissions; all but one were due to RTIs, and seven were associated with at least one fatality. Conclusions  This study elucidated injury epidemiology in Malawi and identified questions for future research. Other developing countries should conduct such prospective data collection to identify region-specific injury patterns and to promote injury prevention.     

Prevalence estimates of depression in elderly community-dwelling African Americans in Indianapolis and Yoruba in Ibadan, Nigeria

BACKGROUND: This is a community-based longitudinal epidemiological comparative study of elderly African Americans in Indianapolis and elderly Yoruba in Ibadan, Nigeria. METHOD: A two-stage study was designed in which community-based individuals were first screened using the Community Screening Interview for Dementia. The second stage was a full clinical assessment, which included use of the Geriatric Depression Scale, of a smaller sub-sample of individuals selected on the basis of their performance in the screening interview. Prevalence of depression was estimated using sampling weights according to the sampling stratification scheme for clinical assessment. RESULTS: Some 2627 individuals were evaluated at the first stage in Indianapolis and 2806 in Ibadan. All were aged 69 years and over. Of these, 451 (17.2%) underwent clinical assessment in Indianapolis, while 605 (21.6%) were assessed in Ibadan. The prevalence estimates of both mild and severe depression were similar for the two sites (p=0.1273 and p=0.7093): 12.3% (mild depression) and 2.2% (severe depression) in Indianapolis and 19.8% and 1.6% respectively in Ibadan. Some differences were identified in association with demographic characteristics; for example, Ibadan men had a significantly higher prevalence of mild depression than Indianapolis men (p<0.0001). Poor cognitive performance was associated with significantly higher rates of depression in Yoruba (p=0.0039). CONCLUSION: Prevalence of depression was similar for elderly African Americans and Yoruba despite considerable socioeconomic and cultural differences between these populations.     

Risk of mortality for dementia in a developing country: the Yoruba in Nigeria

BACKGROUND: Limited data exist on the impact of dementia in developing nations, including its association with mortality. OBJECTIVE: The purpose of this paper is to assess the relationship between dementia and five-year mortality on a community dwelling elderly Yoruba population in the developing country of Nigeria and to compare those results with those from an elderly African-American community in Indianapolis. METHODS: A two-phase design was used to ascertain dementia status in two sites. In the first phase, the Community Screening Instrument for Dementia (CSI-D) was administered. In the second phase, subjects were sampled for the clinical assessment according to their CSI-D performance category. Proportional hazards regression was used to assess the relationship between mortality and cognitive status at both sites after adjusting for demographics and chronic disease conditions. RESULTS: For the entire screened population, poor and intermediate performance on the CSI-D is associated with increased mortality at both sites; however the effect of CSI-D performance did not significantly differ between the two sites. For the clinically assessed sample, dementia was significantly associated with increased mortality at both sites (Ibadan RR = 2.83, Indianapolis RR = 2.05), but the effect was not significantly different across the two sites. CONCLUSION: Dementia resulted in an increased risk of mortality for Yoruba of a magnitude similar to African-Americans suggesting that the impact of dementia on mortality risk may be similar for developing and developed countries.     

RegR,a global LacI/GalR family regulator,modulates virulence and competence in Streptococcus pneumoniae

The homolactic and catalase-deficient pathogen Streptococcus pneumoniae is not only tolerant to oxygen but requires the activity of its NADH oxidase, Nox, to develop optimal virulence and competence for genetic transformation. In this work, we show that the global regulator RegR is also involved in these traits. Genetic dissection revealed that RegR regulates competence and the expression of virulence factors, including hyaluronidase. In bacteria grown in vitro, RegR represses hyaluronidase. At neutral pH, it increases adherence to A549 epithelial cells, and at alkaline pH, it acts upstream of the CiaRH two-component signaling system to activate competence. These phenotypes are not associated with changes in antibiotic resistance, central metabolism, and carbohydrate utilization. Although the RegR(0) (where 0 indicates the loss of the protein) mutation is sufficient to attenuate experimental virulence of strain 23477 in mice, the introduction of an additional hyl(0) (where 0 indicates the loss of function) mutation in the RegR(0) strain 23302 dramatically reduces its virulence. This indicates that residual virulence of the RegR(0) Hyl(+) derivative is due to hyaluronidase and supports the dual role of RegR in virulence. This LacI/GalR regulator, not essential for in vitro growth in rich media, is indeed involved in the adaptive response of the pneumococcus via its control of competence, adherence, and virulence.     

In vitro synergistic activity of NCL195 in combination with colistin against Gram-negative bacterial pathogens

In this study, the potential of using the novel antibiotic NCL195 combined with subinhibitory concentrations of colistin against infections caused by Gram-negative bacteria (GNB) was investigated. We showed synergistic activity of the combination NCL195 + colistin against clinical multidrug-resistant GNB pathogens with minimum inhibitory concentrations (MICs) for NCL195 ranging from 0.5–4 μg/mL for Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, whereas NCL195 alone had no activity. Transmission electron microscopy of the membrane morphology of E. coli and P. aeruginosa after single colistin or combination drug treatment showed marked ultrastructural changes most frequently in the cell envelope. Exposure to NCL195 alone did not show any change compared with untreated control cells, whereas treatment with the NCL195 + colistin combination caused more damage than colistin alone. Direct evidence for this interaction was demonstrated by fluorescence-based membrane potential measurements. We conclude that the synergistic antimicrobial activity of the combination NCL195 + colistin against GNB pathogens warrants further exploration for specific treatment of acute GNB infections.