Antigen Rapid Diagnostic Tests Research Articles

Plasmodium falciparum malaria parasitaemia among indigenous Batwa and non-indigenous communities of Kanungu district, Uganda.

BackgroundThe indigenous Batwa of southwestern Uganda are among the most highly impoverished populations in Uganda, yet there is negligible research on the prevalence of malaria in this population. Plasmodium falciparum malaria parasitaemia prevalence was estimated in an indigenous Batwa and a non-indigenous neighbouring population, and an exploration of modifiable risk factors was carried out to identify potential entry points for intervention. Additionally, evidence of zooprophylaxis was assessed, hypothesizing that livestock ownership may play a role in malaria risk.MethodsTwo cross-sectional surveys of Batwa and non-Batwa communities were carried out in Kanungu District, Uganda in July 2013 and April 2014 based on a census of adult Batwa and a two-stage systematic random sample of adult non-Batwa in ten Local Councils where Batwa settlements are located. A community-based questionnaire and antigen rapid diagnostic test for P. falciparum were carried out in the cross-sectional health surveys. A multivariable logistic regression model was built to identify risk factors associated with positive malaria diagnostic test. A subset analysis of livestock owners tested for zooprophylaxis.ResultsBatwa experienced higher prevalence of malaria parasitaemia than non-Batwa (9.35 versus 4.45 %, respectively) with over twice the odds of infection (OR 2.21, 95 % CI 1.23–3.98). Extreme poverty (OR 1.96, 95 % CI 0.98–3.94) and having an iron sheet roof (OR 2.54, 95 % CI 0.96–6.72) increased the odds of infection in both Batwa and non-Batwa. Controlling for ethnicity, wealth, and bed net ownership, keeping animals inside the home at night decreased the odds of parasitaemia among livestock owners (OR 0.29, 95 % CI 0.09–0.94).ConclusionA health disparity exists between indigenous Batwa and non-indigenous community members with Batwa having higher prevalence of malaria relative to non-Batwa. Poverty was associated with increased odds of malaria infection for both groups. Findings suggest that open eaves and gaps in housing materials associated with iron sheet roofing represent a modifiable risk factor for malaria, and may facilitate mosquito house entry; larger sample sizes will be required to confirm this finding. Evidence for possible zooprophylaxis was observed among livestock owners in this population for those who sheltered animals inside the home at night.

Évaluation prospective des prescriptions antibiotiques d’un échantillon de médecins généralistes français

The aim of our study was to assess the quality of antibiotic prescriptions in a sample of general practitioners (GPs) receiving junior doctors in training, whatever the motive of the prescription. We performed a prospective observational study of all antibiotics prescribed in October 2012 by 21 GPs working in southeastern France. Two specialists (general medicine and infectious diseases) independently assessed the compliance with recommendations of antibiotic prescriptions using a validated algorithm. Two hundred and thirty-two antibiotic courses were prescribed, mainly for low respiratory tract infections (30%), ENT (26%), urinary tract (22%) or skin (13%) infections. Forty prescriptions were considered as appropriate (17%), 77 as inappropriate (33%; mainly due to a non-recommended molecule choice [77%] or a too long treatment duration [44%]) and 115 prescriptions were unnecessary (50%), due to diagnostic issues. There were wide variations between GPs. An essential laboratory or imaging investigation was missing for 36% of prescriptions: chest X-ray for pneumonia (80% were missing), rapid antigen diagnostic test for acute pharyngitis (23% missing) and urine dipstick for urinary tract infections (80% missing). Fluoroquinolones and macrolides/synergistins accounted for 31% of the prescriptions, and were associated with a lower prevalence of appropriate prescriptions (7% and 2% respectively, P<0.001). There was a co-prescription of anti-inflammatory drugs in 15% of the cases. The misuse of antibiotics was frequent in this study. Improving the diagnostic workout is of paramount importance. Urgent actions are needed to improve antibiotic use in general practice.

Ultrasound diagnosis of malaria: examination of the spleen, liver, and optic nerve sheath diameter.

Over 90% of all cases of malaria worldwide occur in Africa. Current methods of diagnosis are time and labor intensive, and could lead to delayed treatment. In this study we investigated the effectiveness of measurements of spleen, liver, and optic nerve sheath diameter (ONSD) in identifying patients with malaria or severe malaria through the use of hand-held ultrasound devices. We recruited 40 adult patients with malaria and 16 adult control subjects at two hospitals in Mwanza, Tanzania. Ultrasonographic diagnosis was compared with rapid antigen diagnostic test and peripheral blood smear as the gold standards. An receiver operating characteristic curve test was performed to determine the most optimal diagnostic threshold for malaria and severe malaria, using each of the measurements for liver size, spleen size, and ONSD. The thresholds were determined to be >12 cm for spleen length and >15.1 cm for liver length, whereas ONSD was not significant in this study. The sensitivities for malaria diagnosis were 66.7% and 58.3% for liver and spleen length respectively, suggesting that these measurements may not be suitable for identifying patients with severe malaria. However, the high specificity of 90.9% for spleen length and the acceptable specificity of 75.0% for liver length suggest that these measurements can be used as a method to eliminate false-positive diagnoses (i.e. patients who do not have severe malaria but are classified as having it by a test with a high sensitivity), giving a high positive predictive value. We report a high specificity for spleen size and a moderate specificity for liver size in the ultrasonographic diagnosis of severe malaria. Thus when paired with a highly sensitive method of malaria diagnosis, ultrasonographic measurement of spleen and liver size is promising as part of a diagnostic algorithm for malaria. It could be used to stratify risk in patients diagnosed with malaria and assist in their triage. If no sensitive tests are available, ultrasound might be useful to suggest malaria as a cause of a patient's constellation of clinical symptoms.

Analysis of Different Recommendations From International Guidelines for the Management of Acute Pharyngitis in Adults and Children

BackgroundStreptococcal pharyngitis is a frequently observed condition, but its optimal management continues to be debated. ObjectiveThe goal of this study was to evaluate the available guidelines, developed at the national level, for the management of streptococcal pharyngitis in Western countries, with a focus on their differences. MethodsA literature search was conducted of the Cochrane Library, EMBASE, TRIP, and MEDLINE databases from their inception (1993 for the Cochrane Library, 1980 for EMBASE, 1997 for TRIP, and 1966 for MEDLINE) through April 25, 2010. The following search terms were used: pharyngitis, sore throat, tonsillitis, pharyngotonsillitis, Streptococcus pyogenes, Group A β-haemolytic Streptococcus pyogenes, and streptococcal pharyngitis. Searches were limited to type of article or document (practice guideline or guideline) with no language restrictions or language limits. ResultsTwelve national guidelines were identified: 6 from European countries (France, United Kingdom, Finland, Holland, Scotland, and Belgium), 5 from the United States, and 1 from Canada. Recommendations differ substantially with regard to the use of a rapid antigen diagnostic test or throat culture and the indications for antibiotic treatment. The North American, Finnish, and French guidelines recommend performing one timely microbiologic investigation in suspected cases, and prescribing antibiotics in confirmed cases to prevent suppurative complications and acute rheumatic fever. According to the remaining European guidelines, however, acute sore throat is considered a benign, self-limiting disease. Microbiologic tests are not routinely recommended by these latter guidelines, and antibiotic treatment is reserved for well-selected cases. The use of the Centor score, for evaluation of the risk of streptococcal infection, is recommended by several guidelines, but subsequent decisions on the basis of the results differ in terms of which subjects should undergo microbiologic investigation. All guidelines agree that narrow-spectrum penicillin is the first choice of antibiotic for the treatment of streptococcal pharyngitis and that treatment should last for 10 days to eradicate the microorganism. Once-daily amoxicillin was recommended by 2 US guidelines as equally effective. ConclusionThe present review found substantial discrepancies in the recommendations for the management of pharyngitis among national guidelines in Europe and North America.

Better diagnosis and treatment of throat infections caused by group A β-haemolytic streptococci

This study aims to assess the diagnostic value of a rapid streptococcal antigen test in addition to four clinical features in patients with sore throat, using throat culture and antibody titre as reference tests, and to evaluate the efficacy of the current antibiotics used in the treatment of throat infections caused by group A β-haemolytic streptococcus (GABHS). Four clinical features (fever [history of] ≥38˚C, lack of cough, tonsillar exudate, and anterior cervical lymphadenopathy) are recorded in 355 patients aged four years to ≥15 years. A rapid antigen diagnostic test (RADT) is performed, as well as a throat culture. Antistreptolysin O (ASO) titre is performed in patients ≥11 years. GABHS from patients are tested for susceptibility to different antibiotics. Throat cultures were positive for GABHS in 19% patients. Rapid tests were positive in 24%. Compared with throat culture, the rapid test gave a sensitivity of 91%, specificity of 91%, positive predictive value of 73% and a negative predictive value of 98%. For patients with three or four clinical features, however, the sensitivity was considerably higher at 97%. Using the ASO test as a reference, no association was found between RADT and culture results. Zithromax showed the highest prescription rate (25.5%) and produced a high cure rate (91%) in patients with GABHS pharyngitis.