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Pneumocystis pneumonia (PCP) has been considered a rare disease in sub-Saharan Africa. However, a rising prevalence has been noted recently. The objective of this study was to determine the relative prevalence of PCP and other pulmonary opportunistic diseases in patients infected with HIV in Ethiopia. 131 consecutive patients with respiratory symptoms and atypical chest X-ray, who were sputum smear-negative for AFB and seroreactive for HIV, underwent clinical evaluation and investigation for Pneumocystis jiroveci and Mycobacterium tuberculosis from sputum and bronchoalveolar lavage (BAL), and fungal and bacterial pathogens from BAL alone. Bacterial infections, Pneumocystis pneumonia (PCP) and pulmonary tuberculosis (PTB) occurred in 44 (33.6%), 39 (29.7%) and 31 (23.7%) patients, respectively. Pulmonary Kaposi sarcoma and non-specific interstitial pneumonitis occurred in 4 patients each. In a multivariate regression model, predictors of PCP were typical chest X-ray and low CD4 count while purulent sputum predicted bacterial infection. The sensitivity of physicians and chest X-ray diagnosis was particularly low for PTB and bacterial infections. We conclude that chronic bacterial infection and Pneumocystis pneumonia are important differential diagnoses in HIV-infected, smear-negative PTB patients presenting with atypical chest X-ray. We therefore need to escalate the use of preventive and highly active antiretroviral (HAART) treatment in order to prevent a PCP epidemic.  相似文献   
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A study was conducted to determine the role of non-biting cyclorrhaphan flies as carriers of intestinal parasites in slum areas of Addis Ababa from January 2004 to June 2004. A total of 9550 flies, comprising of at least seven species were collected from four selected sites and examined for human intestinal parasites using the formol-ether concentration method. The dominant fly species was Chrysomya rufifacies (34.9%) followed by Musca domestica (31%), Musca sorbens (20.5.%), Lucina cuprina (6.8%), Sarcophaga sp. (2.8%), Calliphora vicina (2.2%) and Wohlfahrtia sp. (1.8%). Six intestinal helminths (Ascaris lumbricoides, Trichuris trichiura, hookworms, Hymenolepis nana, Taenia spp. and Strongyloides stercoralis) and at least four protozoan parasites (Entamoeba histolytica/dispar, Entamoeba coli, Giardia lamblia and Cryptosporidium sp.) were isolated from both the external and gut contents of the flies. A. lumbricoides and T. trichiura among the helminths and E. histolytica/dispar and E. coli among the protozoans were the dominant parasites detected both on the external and in the gut contents of the flies, but occurring more in the latter. Among the flies, C. rufifacies and M. sorbens were the highest carriers of the helminth and protozoan parasites, respectively. The public health significance of these findings is highlighted.  相似文献   
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OBJECTIVE: The efficacy of mebendazole and albendazole in the treatment of Ascaris lumbricoides and hookworm infections was evaluated in school children in an area with long time exposure for broad spectrum anthelminthic drugs. RESULTS: Mebendazole exhibited cure rates of 90.6% and 83.5%; egg reduction rates of 96.7% and 94.2% against Ascaris lumbricoides and hookworm infections respectively. Albendazole showed a cure rate of 83.9% and egg reduction rate of 96.3% against Ascaris lumbricoides and a cure rate of 84.2% and egg reduction rate of 95% against hookworm infection. Albendazole appeared to be more effective against hookworm infection (egg reduction rate of 95% versus 94.2%, p = 0.04). CONCLUSIONS: Mebendazole and albendazole showed reduced efficacy against Ascaris lumbricoides and hookworm infections at the recommended doses. This may be a sign for emergence of drug resistance in this region. Care in routine use of the anthelminthes and continuous drug efficacy surveillance is recommended.  相似文献   
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We report a patient with osseous lesions of his fingers and thumbs that eventually were proved to be a manifestation of systemic sarcoidosis. This had been mis-diagnosed as tuberculosis and the patient had previously been treated without effect with two full courses of anti-tuberculosis chemotherapy. Eventually the clinical and radiological suspicions were confirmed by biopsy.  相似文献   
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Background and objectives: Measurement of GFR is important for the management of chronic kidney disease (CKD). Although bolus administration of radiocontrast agents is commonly used to measure GFR, the optimal duration of sampling to assess their plasma clearance is unknown. The purpose of this study was to evaluate whether the duration of plasma sampling influences precision and estimation of GFR.Design, setting, participants, & measurements: GFR was measured by sampling plasma 12 times over 5 h in 56 patients with CKD (mean age 64 yr, 98% men, 79% Caucasian, 34% diabetics, estimated GFR 31.8 ± 14.2 ml/min/1.73 m2). In a subset of 12 patients we measured GFR by sampling plasma 17 times over 10 h.Results: Short sampling intervals considerably overestimated GFR measured using total plasma iothalamate clearance, especially in larger patients. In the higher estimated GFR group (>30 ml/min/1.73m2), the 5-h GFR was 17% higher and 2-h GFR 54% higher compared with the 10-h GFR, which averaged 40.3 ml/min/1.73 m2. In the lower estimated GFR group (<30 ml/min/1.73m2), the 5-h GFR was 36% higher and 2-h GFR 126% higher compared with the 10-h GFR, which averaged 22.2 ml/min/1.73 m2. Short sampling duration also reduced the precision of the estimated GFR from 1.67% for 10-h GFR, to 3.48% for 5-h GFR, and to 7.07% for 2-h GFR.Conclusions: GFR measured over a longer duration with multiple plasma samples spanning the distribution and elimination phases may improve precision and provide a better measure of renal function.The clinical manifestations of chronic kidney disease (CKD) are heterogenous, but it is generally accepted that the staging of CKD rests upon an accurate knowledge of GFR (1). Although urinary clearance of radioactive iothalamate has been used as the reference method to measure GFR (2), many clinical and research laboratories now use plasma clearance of nonradioactive radiocontrast dyes instead (37). Plasma clearance of iothalamate can be measured either after continuous infusion of iothalamate to achieve steady state and measuring plasma iothalamate (4,5,7), or after an intravenous bolus (3,6,8). The latter technique involves administering a bolus dose of iothalamate or another radiocontrast dye and sampling blood at timed intervals to study its pharmacokinetics. We and others have reported that plasma iothalamate clearance provides improved precision over urinary clearances (8,9). Because of improved precision, the plasma iothalamate clearance technique appears attractive for longitudinal studies in which sample size can be reduced to detect a given change in GFR (9).The optimal duration of plasma sampling to best ascertain GFR remains undefined—no minimum duration of sampling is recommended. Accordingly, uncertainty exists when planning the optimal duration of GFR studies for the long-term follow-up renal function. Review of published work reveals that the duration of plasma iothalamate clearances measurement has varied anywhere between 2 to 10 h (8,1012). In a study that measured plasma iothalamate concentration time profile over 10 h (12), plasma clearance was noted to be log-linear in all instances after 120 min, whereas another study reported that a 2-h time frame was perfectly adequate (10). A more recent multicenter study in children in the United States suggested 5 h as an adequate time frame for sampling (6).We sought to evaluate the optimal duration of measurement of plasma iothalamate clearance in a cohort of patients with CKD. We hypothesized that short studies would overestimate GFR and that longer studies would reduce this error. We reasoned that short studies in patients with lower GFR would be associated with greater discrepancy compared with studies with longer sampling duration and tested the hypothesis that shorter duration studies would sacrifice precision compared with longer studies.  相似文献   
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The development of irrigation schemes by dam construction has led to an increased risk of malaria in Tigray, Ethiopia. We carried out a pilot study near a microdam to assess whether environmental management could reduce malaria transmission by Anopheles arabiensis, the main vector in Ethiopia. The study took place in Deba village, close to a dam; Maisheru village, situated 3-4 km away from the dam, acted as a control. Baseline entomological and clinical data were collected in both villages during the first 12 months. Source reduction, involving filling, draining and shading of potential mosquito-breeding habitats was carried out by the community of Deba in the second year and routine surveillance continued in both villages during the second year. Anopheles arabiensis was highly anthropophilic (Human Blood Index=0.73), biting early in the night before people went to bed. The major breeding habitats associated with the dam were areas of seepage at the dam base (28%), leaking irrigation canals (16%), pools that formed along the bed of streams from the dam (13%), and man-made pools (12%). In the pre-intervention year, 5.9-7.2 times more adult vectors were found in the dam village compared with the control village. There was a 3.1% higher prevalence of an enlarged spleen in children under 10 years in the dam village than in the control village during the pre-intervention period, but no statistically significant difference was found in the incidence of falciparum malaria between the two villages during the same period. Source reduction was associated with a 49% (95% CI=46.6-50.0) relative reduction in An. arabiensis adults in the dam village compared with the pre-intervention period. There were very few cases of malaria during the intervention period in both villages making it impossible to judge whether malaria incidence had been reduced. These preliminary findings suggest that in areas of low intensity transmission community-led larval control may be a cheap and effective method of controlling malaria. Further, large-scale studies are needed to confirm these findings.  相似文献   
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Background

Perinatal mortality is reported to be five times higher in developing than in developed nations. Little is known about the commonly associated risk factors for perinatal mortality in Southern Nations National Regional State of Ethiopia.

Methods

A case control study for perinatal mortality was conducted in University hospital between 2008 and 2010. Cases were stillbirths and early neonatal deaths. Controls were those live newborns till discharged from the hospital. Subgroup binary logistic regression analyses were done to identify associated risk factors for perinatal mortality, stillbirths and early neonatal deaths.

Results

A total of 1356 newborns (452 cases and 904 controls) were included in this analysis. The adjusted perinatal mortality rate was 85/1000 total delivery. Stillbirths accounted for 87% of total perinatal mortality. The proportion of hospital perinatal deaths was 26%. Obstructed labor was responsible for more than one third of perinatal deaths. Adjusted odds ratios revealed that obstructed labor, malpresentation, preterm birth, antepartum hemmorrhage and hypertensive disorders of pregnancy were independent predictors for high perinatal mortality. In the subgroup analysis, among others, obstructed labor and antepartum hemorrhage found to have independent association with both stillbirths and early neonatal deaths.

Conclusion

The perinatal mortality rate was more than two fold higher than the estimated national perinatal mortality;and obstructed labor, malpresentation, preterm birth, antepartum hemmorrhage and hypertensive disorders of pregnancy were independent predictors. The reason for the poor progress of labor and developing obstructed labor is an area of further investigation.  相似文献   
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