High Prevalence of Tuberculosis among Adults with Fever Admitted at a Tertiary Hospital in North-western Tanzania

Tuberculosis is a leading cause of death in developing countries where HIV is endemic. This hospital based study was done to estimate the magnitude of pulmonary and extra-pulmonary tuberculosis and to determine predictors of tuberculosis among febrile adults admitted at Bugando Medical Centre (BMC), Mwanza, Tanzania. A total of 346 adults febrile patients admitted in medical wards were studied. Sputum for AFB microscopy and chest X-rays was used to diagnose tuberculosis. Clinical features were collected using standardized data collection tool. HIV testing and CD4 counts were determined. Data were analyzed using STATA version 11 software. Of 346 febrile adults patients 116 (33.5%) were diagnosed to have tuberculosis; of which 79 (68.1%) and 37 (31.9%) had pulmonary tuberculosis (PTB) and extra-pulmonary tuberculosis, respectively. Smear negative PTB were more common in HIV positive than in HIV negative patients (50% vs. 18.5%, p=0.007). Extra-pulmonary tuberculosis was more common in HIV positive patients than pulmonary tuberculosis (86.4% vs. 13.6%), p=0.0001). On multivariate logistic regression analysis the predictors of tuberculosis were; age above 35 years (OR =2.38, p=0.007), cardinal symptoms (OR=37, p<0.0001), pleural effusion (OR=24, p=0.0001), and HIV status (OR =3.2, p=0.0001). Of 79 patients with PTB, 48 (60.7%) were AFB smear positive and 31(39.3%) were AFB smear negative. HIV patients with smear negative tuberculosis had significantly lower CD4 count than HIV patients with smear positive tuberculosis (63.5 cells/μl versus 111.5 cells/μl) [Mann- Whitney test p=0.0431]]. No different in mortality was observed between patients with TB and those without TB admitted in BMC medical wards (28.5% vs. 23.0%, p= 0.1318). Tuberculosis is the commonest cause of fever among adults patients admitted at BMC and is predicted by age above 35 years, positive HIV status, cardinal PTB symptoms, and pleural effusion. Routinely TB screening is highly recommended among adults with fever, cough, night sweating and wasting in countries where HIV is endemic.\u

High Prevalence of Non-Typhoid Salmonella Bacteraemia Among Febrile HIV Adult Patients Admitted at a Tertiary Hospital, North-Western Tanzania.

Bacterial blood stream infections constitute a significant public-health problem and it is an important cause of morbidity and mortality in HIV infected patients. Little is known in developing countries regarding salmonella bacteraemia among HIV patients. The purpose of this study was to determine the bacterial pathogens causing blood stream infection among febrile adults attending in a tertiary hospital North-Western, Tanzania. A prospective cross-sectional study involving 346 consecutive, febrile adult patients admitted at Bugando Medical Centre was conducted. Demographic and other data were collected using standardized questionnaires. Blood culture was done followed by susceptibility testing using disc diffusion method. HIV testing was also performed as per Tanzania national algorithm and total white blood cell counts and CD4+ counts determined. Of 346 febrile adult patients 33 (9.5%) had blood stream infections. The common isolates were Salmonella spp 13(39.4%), Escherichia coli 8 (24.2%), Streptococcus pneumonia 5(15.2%), Staphylococcus aureus 4(12.1%), Citrobacter spp 1(3%), Streptococcus pyogenes 1(3%) and Klebsiella pneumonia 1(3%). A total of 156 (45.1%) patients were HIV infected; of whom 12/156 (7.6%) were infected by non-typhoid Salmonella spp compared to 1/190 (0.5%) of non-HIV infected patients (RRR 11.2, p=0.029) infected with Salmonella typhi. HIV infected patients with bacteraemia had significantly lower CD4+ count than those without bacteraemia (median 28 vs. 88 cells/ml, p=0.01). Patients with salmonella bacteraemia had significantly lower median of WBC than those with non-salmonella as well as those without bacteraemia (median, 3.6 vs. 17.5 vs. 9.8x109, p=0.0001). All Salmonella spp were sensitive to ceftriaxone and imipenem, while being 84%, 69.2%, 38% and 8% resistant to chloramphenicol, ampicillin, sulphamethaxazole/trimethoprim and ciprofloxacin respectively. Predictors of mortality were HIV infection (OR 2.3, p=0.006), Glasgow coma score of less than 15 (OR 3.4, p=0.0001) and night sweats (OR 2.4, p=0.014). Non-typhoid Salmonella spp that are highly resistant to common antibiotics are predominant cause of bacterial blood stream infection among HIV patients attending Bugando Medical Centre. Continuous surveillance and intervention strategies should be put in place to monitor and manage cases of bloodstream infections in HIV-positive patients in Mwanza, Tanzania

Species-Rich Grassland as an Ecological Good in an Outcome-Based Payment Scheme

Agriculture plays an important role in protecting the biodiversity of the rural environment. Since the reform of the EU\u27s common agricultural policy (CAP) in 1992, agri-environment schemes have been supported by the EU within the framework of the second pillar of CAP. In these programmes, farmers were rewarded for environmental services. The predominantly action-oriented programmes imply particular disadvantages; they tend to lack economic efficiency and to fail with regard to the conservation and improvement of biodiversity (Kleijn & Sutherland, 2003; Wilhelm, 1999). This situation was the starting point for the development of an outcome-based payment scheme. We focus on the process of defining ecological goods - in particular with regard to grassland - as the results of ecological services, which are to be remunerated by means of this innovative payment system

Key signal contributions in photothermal deflection spectroscopy

We report on key signal contributions in photothermal deflection spectroscopy (PDS) of semiconductors at photon energies below the bandgap energy and show how to extract the actual absorption properties from the measurement data. To this end, we establish a rigorous computation scheme for the deflection signal including semi-analytic raytracing to analyze the underlying physical effects. The computation takes into account linear and nonlinear absorption processes affecting the refractive index and thus leading to a deflection of the probe beam. We find that beside the linear mirage effect, nonlinear absorption mechanisms make a substantial contribution to the signal for strongly focussed pump beams and sample materials with high two-photon absorption coefficients. For example, the measured quadratic absorption contribution exceeds 5% at a pump beam intensity of about ${1.3}\times{10^{5}}\;{W}/{cm^{2}}$ in Si and at ${5}\times{10^{4}}\;{W}/{cm^{2}}$ in GaAs. In addition, our method also includes thermal expansion effects as well as spatial gradients of the attenuation properties. We demonstrate that these effects result in an additional deflection contribution which substantially depends on the distance of the photodetector from the readout point. This distance dependent contribution enhances the surface related PDS signal up to two orders of magnitude and may be misinterpreted as surface absorption if not corrected in the analysis of the measurement data. We verify these findings by PDS measurements on crystalline silicon at a wavelength of 1550 nm and provide guidelines how to extract the actual attenuation coefficient from the PDS signal.Comment: 10 pages, 16 figures, submitted to Journal of Applied Physiv

In vitro activity of cefepime against extended spectrum β-lactamase- producing Escherichia coli and Klebsiella pneumoniae from clinical specimens at Bugando Medical Centre, Mwanza, Tanzania

There is an increase in isolation of extended spectrum beta-lactamase (ESBL) producing isolates from clinical samples worldwide. In developing countries the treatment option of ESBL producing isolates is limited. Recently fourth generation cephalosporins have been introduced for use in Tanzania. This study was done to determine in vitro activity of cefepime against ESBL producing clinical isolates. Disc diffusion testing was performed to 235 ESBL producing isolates; of which 73 (31%) were Escherichia coli and 162 (69%) Klebsiella pneumoniae. The sensitivity rate of E. coli and K. pneumoniae to cefepime were 15.1% and 4.3%, respectively (P=0.012); intermediate sensitivity rate was observed in 13.7% for E. coli and 19.8% for K. pneumoniae. The mean zones of inhibition diameter among sensitive isolates were 24.9mm and 20.0mm for E. coli and K. pneumonia, respectively (P=0.0085). Cefepime is less active against ESBL producing organisms; hence the use of this drug should be guided using local resistance profile

Direct Wolf summation of a polarizable force field for silica

We extend the Wolf direct, pairwise r^(-1) summation method with spherical truncation to dipolar interactions in silica. The Tangney-Scandolo interatomic force field for silica takes regard of polarizable oxygen atoms whose dipole moments are determined by iteration to a self-consistent solution. With Wolf summation, the computational effort scales linearly in the system size and can easily be distributed among many processors, thus making large-scale simulations of dipoles possible. The details of the implementation are explained. The approach is validated by estimations of the error term and simulations of microstructural and thermodynamic properties of silica.Comment: See http://link.aip.org/link/?JCP/132/194109 - 8 pages, 6 figures. Changes in v3: Copyright notice added, minor typographical changes. Changes in v2: 1. Inserted Paragraph in Sec. IV B describing the limitations of the TS potential. 2. We corrected transcription errors in Tab. II, and adjusted the deviation percentages mentioned in Sec. IV B, first paragraph, accordingl