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3.
Lancet Infect Dis ; 24(3): e189-e195, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37837983

ABSTRACT

Non-timely reporting, selective reporting, or non-reporting of clinical trial results are prevalent and serious issues. WHO mandates that summary results be available in registries within 12 months of study completion and published in full text within 24 months. However, only a limited number of clinical trials in infectious diseases, including those done during the COVID-19 pandemic, have their results posted on ClinicalTrials.gov. An analysis of 50 trials of eight antiviral drugs tested against COVID-19 with a completion date of at least 2 years ago revealed that only 18% had their results published in the registry, with 40% not publishing any results. Non-timely and non-reporting practices undermine patient participation and are ethically unacceptable. Strategies should include obligatory reporting of summary results within 12 months in clinical trial registries, with progress towards peer-reviewed publication within 24 months indicated. Timely publication of research papers should be encouraged through an automated flagging mechanism in clinical trial registries that draws attention to the status of results reporting, such as a green tick for trials that have reported summary results within 12 months and a red tick in case of failure to do so. We propose the inclusion of mandatory clinical trial reporting standards in the International Conference on Harmonization Good Clinical Practice guidelines, which should prohibit sponsor contract clauses that restrict reporting (referred to as gag clauses) and require timely reporting of results as part of the ethics committees' clearance process for clinical trial protocols.


Subject(s)
COVID-19 , Communicable Diseases , Humans , Pandemics , Communicable Diseases/drug therapy , Registries , Bias
4.
J Clin Med ; 11(10)2022 May 23.
Article in English | MEDLINE | ID: mdl-35629060

ABSTRACT

Weitzman et al. used PubMed text mining to determine the trends of antimalarial resistance over the last 40 years [...]

5.
Clin Infect Dis ; 72(7): 1171-1178, 2021 04 08.
Article in English | MEDLINE | ID: mdl-31998942

ABSTRACT

BACKGROUND: Rickettsial disease (RD) is a prevalent and underestimated cause of febrile illness worldwide, especially in the absence of an inoculation eschar. We attempted to quantify this underestimation at our clinic, by investigating past cases of febrile illness in travelers who had tested negative for leptospirosis, a disease that can initially present similarly to non-eschar RD, and which we routinely consider when other important causes of unspecified febrile illness have tested negative. METHODS: We performed a retrospective analysis in febrile returned travelers from Asia, Africa, or the Americas between 2010 and 2017, who had tested negative for leptospirosis. Serologic immunofluorescence assays were performed for Orientia tsutsugamushi (scrub typhus), typhus group, and spotted fever group RD. We performed a medical records review of all patients who tested positive. In case of a fitting medical history, cases were deemed either confirmed (based on convalescent serology) or suspected (based on single serology). RESULTS: Among 97 patients, convalescent serology was available in 16 (16.5%) patients, and a single serology in 81 (83.5%) patients. RD was the likely diagnosis in 8 of 16 (50.0%) patients with convalescent serology, and in 8 of 81 (9.9%) with single serology. Of the 16 confirmed/suspected cases, 11 (69%) had been missed and 7 (44%) had not received adequate empiric antibiotic therapy. CONCLUSIONS: This study shows that non-eschar RD is an important and poorly recognized cause of illness in travelers, even in a specialized travel clinic. A lower threshold to test and treat for RD is warranted in returning travelers with febrile illness.


Subject(s)
Rickettsia Infections , Scrub Typhus , Africa , Asia , Humans , Retrospective Studies , Rickettsia Infections/diagnosis , Rickettsia Infections/epidemiology , Scrub Typhus/diagnosis , Scrub Typhus/epidemiology
6.
Cochrane Database Syst Rev ; 8: CD011871, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31425612

ABSTRACT

BACKGROUND: Early diagnosis of leptospirosis may contribute to the effectiveness of antimicrobial therapy and early outbreak recognition. Nucleic acid and antigen detection tests have the potential for early diagnosis of leptospirosis. With this systematic review, we assessed the sensitivity and specificity of nucleic acid and antigen detection tests. OBJECTIVES: To determine the diagnostic test accuracy of nucleic acid and antigen detection tests for the diagnosis of human symptomatic leptospirosis. SEARCH METHODS: We searched electronic databases including MEDLINE, Embase, the Cochrane Library, and regional databases from inception to 6 July 2018. We did not apply restrictions to language or time of publication. SELECTION CRITERIA: We included diagnostic cross-sectional studies and case-control studies of tests that made use of nucleic acid and antigen detection methods in people suspected of systemic leptospirosis. As reference standards, we considered the microscopic agglutination test alone (which detects antibodies against leptospirosis) or in a composite reference standard with culturing or other serological tests. Studies were excluded when the controls were healthy individuals or when there were insufficient data to calculate sensitivity and specificity. DATA COLLECTION AND ANALYSIS: At least two review authors independently extracted data from each study. We used the revised Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2) to assess risk of bias. We calculated study-specific values for sensitivity and specificity with 95% confidence intervals (CI) and pooled the results in a meta-analysis when appropriate. We used the bivariate model for index tests with one positivity threshold, and we used the hierarchical summary receiver operating characteristic model for index tests with multiple positivity thresholds. As possible sources of heterogeneity, we explored: timing of index test, disease prevalence, blood sample type, primers or target genes, and the real-time polymerase chain reaction (PCR) visualisation method. These were added as covariates to the meta-regression models. MAIN RESULTS: We included 41 studies evaluating nine index tests (conventional PCR (in short: PCR), real-time PCR, nested PCR, PCR performed twice, loop-mediated isothermal amplification, enzyme-linked immunosorbent assay (ELISA), dot-ELISA, immunochromatography-based lateral flow assay, and dipstick assay) with 5981 participants (1834 with and 4147 without leptospirosis). Methodological quality criteria were often not reported, and the risk of bias of the reference standard was generally considered high. The applicability of findings was limited by the frequent use of frozen samples. We conducted meta-analyses for the PCR and the real-time PCR on blood products.The pooled sensitivity of the PCR was 70% (95% CI 37% to 90%) and the pooled specificity was 95% (95% CI 75% to 99%). When studies with a high risk of bias in the reference standard domain were excluded, the pooled sensitivity was 87% (95% CI 44% to 98%) and the pooled specificity was 97% (95% CI 60% to 100%). For the real-time PCR, we estimated a summary receiver operating characteristic curve. To illustrate, a point on the curve with 85% specificity had a sensitivity of 49% (95% CI 30% to 68%). Likewise, at 90% specificity, sensitivity was 40% (95% CI 24% to 59%) and at 95% specificity, sensitivity was 29% (95% CI 15% to 49%). The median specificity of real-time PCR on blood products was 92%. We did not formally compare the diagnostic test accuracy of PCR and real-time PCR, as direct comparison studies were lacking. Three of 15 studies analysing PCR on blood products reported the timing of sample collection in the studies included in the meta-analyses (range 1 to 7 days postonset of symptoms), and nine out of 16 studies analysing real-time PCR on blood products (range 1 to 19 days postonset of symptoms). In PCR studies, specificity was lower in settings with high leptospirosis prevalence. Other investigations of heterogeneity did not identify statistically significant associations. Two studies suggested that PCR and real-time PCR may be more sensitive on blood samples collected early in the disease stage. Results of other index tests were described narratively. AUTHORS' CONCLUSIONS: The validity of review findings are limited and should be interpreted with caution. There is a substantial between-study variability in the accuracy of PCR and real-time PCR, as well as a substantial variability in the prevalence of leptospirosis. Consequently, the position of PCR and real-time PCR in the clinical pathway depends on regional considerations such as disease prevalence, factors that are likely to influence accuracy, and downstream consequences of test results. There is insufficient evidence to conclude which of the nucleic acid and antigen detection tests is the most accurate. There is preliminary evidence that PCR and real-time PCR are more sensitive on blood samples collected early in the disease stage, but this needs to be confirmed in future studies.


Subject(s)
Antibodies, Bacterial/immunology , Leptospira/immunology , Leptospirosis/diagnosis , Nucleic Acids/blood , Polymerase Chain Reaction/methods , Enzyme-Linked Immunosorbent Assay/methods , Humans , Leptospirosis/blood , ROC Curve , Sensitivity and Specificity
7.
BMJ Open ; 8(9): e019642, 2018 09 08.
Article in English | MEDLINE | ID: mdl-30196265

ABSTRACT

OBJECTIVE: To determine which service models and organisational structures are effective and cost-effective for delivering tuberculosis (TB) services to hard-to-reach populations. DESIGN: Embase and MEDLINE (1990-2017) were searched in order to update and extend the 2011 systematic review commissioned by National Institute for Health and Care Excellence (NICE), discussing interventions targeting service models and organisational structures for the identification and management of TB in hard-to-reach populations. The NICE and Cochrane Collaboration standards were followed. SETTING: European Union, European Economic Area, European Union candidate countries and Organisation for Economic Co-operation and Development countries. PARTICIPANTS: Hard-to-reach populations, including migrants, homeless people, drug users, prisoners, sex workers, people living with HIV and children within vulnerable and hard-to-reach populations. PRIMARY AND SECONDARY OUTCOME MEASURES: Effectiveness and cost-effectiveness of the interventions. RESULTS: From the 19 720 citations found, five new studies were identified, in addition to the six discussed in the NICE review. Community health workers from the same migrant community, street teams and peers improved TB screening uptake by providing health education, promoting TB screening and organising contact tracing. Mobile TB clinics, specialised TB clinics and improved cooperation between healthcare services can be effective at identifying and treating active TB cases and are likely to be cost-effective. No difference in treatment outcome was detected when directly observed therapy was delivered at a health clinic or at a convenient location in the community. CONCLUSIONS: Although evidence is limited due to the lack of high-quality studies, interventions using peers and community health workers, mobile TB services, specialised TB clinics and improved cooperation between health services can be effective to control TB in hard-to-reach populations. Future studies should evaluate the (cost-)effectiveness of interventions on TB identification and management in hard-to-reach populations and countries should be urged to publish the outcomes of their TB control systems. PROSPERO REGISTRATION NUMBER: CRD42015017865.


Subject(s)
Delivery of Health Care/organization & administration , Health Education/organization & administration , Models, Organizational , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/epidemiology , Community Health Workers/organization & administration , Drug Users , Europe , HIV Infections/epidemiology , Ill-Housed Persons , Humans , Incidence , Israel , Mobile Health Units/organization & administration , Peer Group , Prisoners , Sex Workers , Transients and Migrants , Tuberculosis, Pulmonary/drug therapy , United States
8.
Travel Med Infect Dis ; 24: 44-50, 2018.
Article in English | MEDLINE | ID: mdl-29753855

ABSTRACT

BACKGROUND: Leptospirosis is a potentially fatal zoonotic disease that is prevalent in travellers. Here, we describe epidemiological and diagnostic characteristics of all returning travellers diagnosed with leptospirosis in the Netherlands between 2009 and 2016. Furthermore, we present a detailed clinical case series of all travellers with leptospirosis who presented at the Academic Medical Center (AMC) in the same period. METHOD: We extracted data from the records of the Dutch Leptospirosis Reference Center (NRL) of all cases of leptospirosis in travellers in the Netherlands from 2009 to 2016. Patients who presented at the AMC were identified and clinical data were extracted from the hospital records. RESULTS: 224 cases of travel-related leptospirosis were included. An increase of cases was observed from 2014 onwards. The majority of cases were male (78.1%), and had travelled to South-East Asia (62.1%). Of 41 AMC cases, 53.7% were hospitalised, but most patients had a relatively mild disease course, with no fatalities. A longer delay in diagnosis and treatment initiation existed in hospitalised compared to non-hospitalised patients, suggesting a benefit of early recognition and treatment. CONCLUSIONS: Leptospirosis was increasingly observed in returning travellers in the Netherlands, and is a diagnosis that should be considered in any returning febrile traveller.


Subject(s)
Leptospirosis/diagnosis , Leptospirosis/epidemiology , Travel-Related Illness , Travel , Zoonoses/diagnosis , Zoonoses/epidemiology , Adolescent , Adult , Aged , Animals , Asia, Southeastern/epidemiology , Child , Communicable Diseases, Imported/diagnosis , Communicable Diseases, Imported/epidemiology , Communicable Diseases, Imported/microbiology , Female , Fever , Humans , Leptospirosis/drug therapy , Leptospirosis/microbiology , Male , Middle Aged , Netherlands/epidemiology , Prevalence , Young Adult , Zoonoses/drug therapy , Zoonoses/microbiology
9.
Am J Trop Med Hyg ; 99(1): 127-135, 2018 07.
Article in English | MEDLINE | ID: mdl-29761761

ABSTRACT

Leptospirosis is a potentially fatal emerging zoonosis with worldwide distribution and a broad range of clinical presentations and exposure risks. It typically affects vulnerable populations in (sub)tropical countries but is increasingly reported in travelers as well. Diagnostic methods are cumbersome and require further improvement. Here, we describe leptospirosis among travelers presenting to the GeoSentinel Global Surveillance Network. We performed a descriptive analysis of leptospirosis cases reported in GeoSentinel from January 1997 through December 2016. We included 180 travelers with leptospirosis (mostly male; 74%; mostly tourists; 81%). The most frequent region of infection was Southeast Asia (52%); the most common source countries were Thailand (N = 52), Costa Rica (N = 13), Indonesia, and Laos (N = 11 each). Fifty-nine percent were hospitalized; one fatality was reported. We also distributed a supplemental survey to GeoSentinel sites to assess clinical and diagnostic practices. Of 56 GeoSentinel sites, three-quarters responded to the survey. Leptospirosis was reported to have been most frequently considered in febrile travelers with hepatic and renal abnormalities and a history of freshwater exposure. Serology was the most commonly used diagnostic method, although convalescent samples were reported to have been collected infrequently. Within GeoSentinel, leptospirosis was diagnosed mostly among international tourists and caused serious illness. Clinical suspicion and diagnostic workup among surveyed GeoSentinel clinicians were mainly triggered by a classical presentation and exposure history, possibly resulting in underdiagnosis. Suboptimal usage of available diagnostic methods may have resulted in additional missed, or misdiagnosed, cases.


Subject(s)
Leptospira/pathogenicity , Leptospirosis/epidemiology , Travel-Related Illness , Travel/statistics & numerical data , Adolescent , Adult , Aged , Anti-Bacterial Agents/therapeutic use , Costa Rica/epidemiology , Doxycycline/therapeutic use , Female , Humans , Incidence , Indonesia/epidemiology , Laos/epidemiology , Leptospira/drug effects , Leptospira/isolation & purification , Leptospirosis/diagnosis , Leptospirosis/drug therapy , Leptospirosis/physiopathology , Male , Middle Aged , Sentinel Surveillance , Surveys and Questionnaires , Thailand/epidemiology
10.
Pulm Circ ; 8(2): 2045894018764629, 2018.
Article in English | MEDLINE | ID: mdl-29480152

ABSTRACT

Pulmonary arterial hypertension (PAH) is a syndrome characterized by progressive lung vascular remodelling, endothelial cell (EC) dysfunction, and excessive inflammation. The primary cilium is a sensory antenna that integrates signalling and fine tunes EC responses to various stimuli. Yet, cilia function in the context of deregulated immunity in PAH remains obscure. We hypothesized that cilia function is impaired in ECs from patients with PAH due to their inflammatory status and tested whether cilia length changes in response to cytokines. Primary human pulmonary and mouse embryonic EC were exposed to pro- (TNFα, IL1ß, and IFNγ) and/or anti-inflammatory (IL-10) cytokines and cilia length was quantified. Chronic treatment with all tested inflammatory cytokines led to a significant elongation of cilia in both control human and mouse EC (by ∼1 µm, P < 0.001). This structural response was PKA/PKC dependent. Intriguingly, withdrawal of the inflammatory stimulus did not reduce cilia length. IL-10, on the other hand, blocked and reversed the pro-inflammatory cytokine-induced cilia elongation in healthy ECs, but did not influence basal length. Conversely, primary cilia of ECs from PAH patients were significantly longer under basal conditions compared to controls (1.86 ± 0.02 vs. 2.43 ± 0.08 µm, P = 0.002). These cilia did not elongate further upon pro-inflammatory stimulation and anti-inflammatory treatment did not impact cilia length. The missing length modulation was specific to cytokine stimulation, as application of fluid shear stress led to increased cilia length in the PAH endothelium. We identified loss of cilia length regulation upon cytokine stimulation as part of the endothelial dysfunction in PAH.

11.
Am J Trop Med Hyg ; 96(5): 1205-1214, 2017 May.
Article in English | MEDLINE | ID: mdl-28500816

ABSTRACT

AbstractThe serum lipid profile in malaria patients has been found to differ from that of healthy controls. We investigated serum lipid profile changes in malaria patients over time compared with patients with other febrile diseases. In total, 217 patients were included in the study (111 malaria patients and 106 symptomatic controls, defined as malaria-negative febrile patients). Serum lipid levels (mmol/L) were significantly lower in malaria patients compared with those with other febrile diseases (total cholesterol [TC] = 3.26 [standard deviation = 0.94] versus 3.97 [1.22; P < 0.001]; high-density lipoprotein cholesterol [HDL-C] = 0.43 [0.47] versus 1.05 [0.67; P < 0.001], low-density lipoprotein cholesterol [LDL-C] = 2.05 [0.76] versus 2.42 [0.90; P < 0.001]. Triglycerides (TGs) levels were higher in malaria patients (1.81 [1.02] versus 1.11 [0.82; P < 0.001]). No significant differences were found for apolipoprotein A1, apolipoprotein B, and lipoprotein(a). Cholesterol levels increased toward reference values on day 28 (TC = 3.26-3.98, P < 0.001; HDL-C = 0.43-0.96, P < 0.001; LDL-C = 2.05-2.60, P < 0.001). TG levels decreased from 1.81 on admission to 1.76 (day 3) and 0.88 (day 28; P = 0.130). Lipid profile changes were not correlated with parasitemia or Plasmodium falciparum histidine-rich protein 2 levels. This study confirms characteristic temporary lipid profile changes in malaria. Lipid profile changes demonstrated a good accuracy to discriminate between malaria and other febrile diseases (area under the curve = 0.80 (95% confidence interval = 0.742-0.863, P < 0.001). Several plausible hypotheses exist regarding the pathophysiology of lipid profile changes in malaria. Further studies to elucidate the precise pathways may lead to improved understanding of the underlying pathophysiology.


Subject(s)
Fever/diagnosis , Malaria, Falciparum/diagnosis , Parasitemia/diagnosis , Adult , Antigens, Protozoan/blood , Apolipoprotein A-I/blood , Apolipoproteins B/blood , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Cohort Studies , Diagnosis, Differential , Female , Fever/blood , Gabon , Humans , Lipid Metabolism , Lipoprotein(a)/blood , Malaria, Falciparum/blood , Malaria, Falciparum/parasitology , Male , Parasitemia/blood , Parasitemia/parasitology , Plasmodium falciparum/growth & development , Protozoan Proteins/blood , ROC Curve , Triglycerides/blood
12.
Lancet Infect Dis ; 17(5): e128-e143, 2017 05.
Article in English | MEDLINE | ID: mdl-28291721

ABSTRACT

Tuberculosis disproportionately affects hard-to-reach populations, such as homeless people, migrants, refugees, prisoners, or drug users. These people often face challenges in accessing quality health care. We did a systematic review of the qualitative literature to identify barriers and facilitators to the uptake of tuberculosis diagnostic and treatment services by people from hard-to-reach populations in all European Union (EU), European Economic Area, EU candidate, and Organisation for Economic Co-operation and Development countries. The 12 studies included in this review mainly focused on migrants. Views on perceived susceptibility to and severity of tuberculosis varied widely and included many misconceptions. Stigma and challenges regarding access to health care were identified as barriers to tuberculosis diagnosis and treatment uptake, whereas support from nurses, family, and friends was a facilitator for treatment adherence. Further studies are required to identify barriers and facilitators to the improved identification and management of tuberculosis in hard-to-reach populations to inform recommendations for more effective tuberculosis control programmes.


Subject(s)
Health Services Accessibility , Transients and Migrants/psychology , Tuberculosis/diagnosis , Tuberculosis/drug therapy , European Union , Family/psychology , Ill-Housed Persons/psychology , Humans , North America , Qualitative Research , Social Stigma
13.
Lancet Infect Dis ; 17(5): e144-e158, 2017 05.
Article in English | MEDLINE | ID: mdl-28291722

ABSTRACT

Tuberculosis is over-represented in hard-to-reach (underserved) populations in high-income countries of low tuberculosis incidence. The mainstay of tuberculosis care is early detection of active tuberculosis (case finding), contact tracing, and treatment completion. We did a systematic review with a scoping component of relevant studies published between 1990 and 2015 to update and extend previous National Institute for Health and Care Excellence (NICE) reviews on the effectiveness of interventions for identifying and managing tuberculosis in hard-to-reach populations. The analyses showed that tuberculosis screening by (mobile) chest radiography improved screening coverage and tuberculosis identification, reduced diagnostic delay, and was cost-effective among several hard-to-reach populations. Sputum culture for pre-migration screening and active referral to a tuberculosis clinic improved identification. Furthermore, monetary incentives improved tuberculosis identification and management among drug users and homeless people. Enhanced case management, good cooperation between services, and directly observed therapy improved treatment outcome and compliance. Strong conclusions cannot be drawn because of the heterogeneity of evidence with regard to study population, methodology, and quality.


Subject(s)
Mass Screening/methods , Tuberculosis/diagnosis , Tuberculosis/drug therapy , Cost-Benefit Analysis , Drug Users/psychology , Global Health , Ill-Housed Persons/psychology , Humans , Mass Screening/economics , Motivation , Transients and Migrants/psychology , Tuberculosis/diagnostic imaging
14.
Malar J ; 15: 163, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26979286

ABSTRACT

BACKGROUND: The World Health Organization recommends malaria to be confirmed by either microscopy or a rapid diagnostic test (RDT) before treatment. The correct use of RDTs in resource-limited settings facilitates basing treatment onto a confirmed diagnosis; contributes to speeding up considering a correct alternative diagnosis, and prevents overprescription of anti-malarial drugs, reduces costs and avoids unnecessary exposure to adverse drug effects. This review aims to evaluate health workers' compliance to RDT results and factors contributing to compliance. METHODS: A PROSPERO-registered systematic review was conducted to evaluate health workers' compliance to RDTs in sub-Saharan Africa, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies published up to November 2015 were searched without language restrictions in Medline/Ovid, Embase, Cochrane Central Register of Controlled Trials, Web of Science, LILACS, Biosis Previews and the African Index Medicus. The primary outcome was health workers treating patients according to the RDT results obtained. RESULTS: The literature search identified 474 reports; 14 studies were eligible and included in the quantitative analysis. From the meta-analysis, health workers' overall compliance in terms of initiating treatment or not in accordance with the respective RDT results was 83% (95% CI 80-86%). Compliance to positive and negative results was 97% (95% CI 94-99%) and 78% (95% CI 66-89%), respectively. Community health workers had higher compliance rates to negative test results than clinicians. Patient expectations, work experience, scepticism of results, health workers' cadres and perceived effectiveness of the test, influenced compliance. CONCLUSIONS: With regard to published data, compliance to RDT appears to be generally fair in sub-Saharan Africa; compliance to negative results will need to improve to prevent mismanagement of patients and overprescribing of anti-malarial drugs. Improving diagnostic capacity for other febrile illnesses and developing local evidence-based guidelines may help improve compliance and management of negative RDT results. TRIAL REGISTRATION: CRD42015016151 (PROSPERO).


Subject(s)
Antimalarials/therapeutic use , Attitude of Health Personnel , Chromatography, Affinity/statistics & numerical data , Diagnostic Tests, Routine/statistics & numerical data , Guideline Adherence , Malaria/diagnosis , Malaria/drug therapy , Africa South of the Sahara , Chromatography, Affinity/methods , Diagnostic Tests, Routine/methods , Humans
15.
Malar J ; 15: 160, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26975570

ABSTRACT

BACKGROUND: There is a need for accurate and field-applicable instruments for the evaluation of the quality of anti-malarial drugs. The aim of this study was to determine the diagnostic accuracy of the NanoRam(®), a handheld Raman spectrometer (RS), to identify anti-malarial drugs. METHODS: In total, 289 anti-malarial drugs collected in a randomized field survey in Gabon were evaluated. The samples were compared with authentic products as supplied by the official manufacturer. To determine the sensitivity and specificity of the handheld NanoRam(®) spectrometer in the identification of anti-malarial drugs, a two-gate reversed-flow design was applied. The standards for reporting of diagnostic accuracy studies (STARD) were followed. The index test was the handheld RS. The reference test standards were thin layer chromatography and high performance liquid chromatography with ultraviolet photo diode array detection. RESULTS: The sensitivity [95% confidence interval (95% CI)] and specificity of the RS to correctly identify an anti-malarial drug were 100% (95% CI 94.9-100%) and 96% (95% CI 92.3-99.0%), respectively. The RS could not differentiate between different batches of the same product or different manufacturers of the same product. Intra-observer agreement for 289 samples was 100%. The average time to conduct the RS was 15 s per sample compared to 45 min per sample for TLC. CONCLUSION: The handheld RS holds promise as an easy-to-use, quick and field-applicable instrument for the evaluation of quality of anti-malarial drugs, potentially empowering pharmacists, drug inspectors and medical regulatory authorities. Trial registration NTR4341 (Dutch Trial Registry).


Subject(s)
Antimalarials/chemistry , Spectrum Analysis/instrumentation , Spectrum Analysis/methods , Gabon , Pilot Projects , Sensitivity and Specificity
16.
Malar J ; 15: 99, 2016 Feb 18.
Article in English | MEDLINE | ID: mdl-26891915

ABSTRACT

BACKGROUND: Pregnancy has been reported to alter the pharmacokinetic properties of anti-malarial drugs, including the different components of artemisinin-based combination therapy (ACT). However, small sample sizes make it difficult to draw strong conclusions based on individual pharmacokinetic studies. The aim of this review is to summarize the evidence of the influence of pregnancy on the pharmacokinetic properties of different artemisinin-based combinations. METHODS: A PROSPERO-registered systematic review to identify clinical trials that investigated the influence of pregnancy on the pharmacokinetic properties of different forms of ACT was conducted, following PRISMA guidelines. Without language restrictions, Medline/PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, LILACS, Biosis Previews and the African Index Medicus were searched for studies published up to November 2015. The following components of ACT that are currently recommend by the World Health Organization as first-line treatment of malaria in pregnancy were reviewed: artemisinin, artesunate, dihydroartemisinin, lumefantrine, amodiaquine, mefloquine, sulfadoxine, pyrimethamine, piperaquine, atovaquone and proguanil. RESULTS: The literature search identified 121 reports, 27 original studies were included. 829 pregnant women were included in the analysis. Comparison of the available studies showed lower maximum concentrations (Cmax) and exposure (AUC) of dihydroartemisinin, the active metabolite of all artemisinin derivatives, after oral administration of artemether, artesunate and dihydroartemisinin in pregnant women. Low day 7 concentrations were commonly seen in lumefantrine studies, indicating a low exposure and possibly reduced efficacy. The influence of pregnancy on amodiaquine and piperaquine seemed not to be clinically relevant. Sulfadoxine plasma concentration was significantly reduced and clearance rates were higher in pregnancy, while pyrimethamine and mefloquine need more research as no general conclusion can be drawn based on the available evidence. For atovaquone, the available data showed a lower maximum concentration and exposure. Finally, the maximum concentration of cycloguanil, the active metabolite of proguanil, was significantly lower, possibly compromising the efficacy. CONCLUSION: These findings suggest that reassessment of the dose of the artemisinin derivate and some components of ACT are necessary to ensure the highest possible efficacy of malaria treatment in pregnant women. However, for most components of ACT, data were insufficient and extensive research with larger sample sizes will be necessary to identify the exact influences of pregnancy on the pharmacokinetic properties of different artemisinin-based combinations. In addition, different clinical studies used diverse study designs with various reported relevant outcomes. Future pharmacokinetic studies could benefit from more uniform designs, in order to increase quality, robustness and effectiveness. STUDY REGISTRATION: CRD42015023756 (PROSPERO).


Subject(s)
Artemisinins/pharmacokinetics , Antimalarials/pharmacokinetics , Antimalarials/pharmacology , Antimalarials/therapeutic use , Artemisinins/pharmacology , Artemisinins/therapeutic use , Drug Combinations , Female , Humans , Malaria/drug therapy , Malaria/physiopathology , Plasmodium falciparum/drug effects , Plasmodium ovale/drug effects , Plasmodium vivax/drug effects , Pregnancy
17.
Malar J ; 14: 273, 2015 Jul 15.
Article in English | MEDLINE | ID: mdl-26169915

ABSTRACT

BACKGROUND: Recent studies alluded to the alarming scale of poor anti-malarial drug quality in malaria-endemic countries, but also illustrated the major geographical gaps in data on anti-malarial drug quality from endemic countries. Data are particularly scarce from Central Africa, although it carries the highest burden of malaria. The aim of this medicine quality field survey was to determine the prevalence of poor-quality anti-malarial drugs in Gabon. METHODS: A field survey of the quality of anti-malarial drugs in Gabonese pharmacies was conducted using the Global Pharma Health Fund Minilab(®) tests, following the Medicine Quality Assessment Reporting Guidelines. Anti-malarial drugs were purchased randomly from selected pharmacies in Gabon. Semi-quantitative thin-layer chromatography (TLC) and disintegration testing were carried out to measure the concentration of active pharmaceutical ingredients (APIs). The samples failing the TLC test were analysed by high-performance liquid chromatography. Following the collection of anti-malarial drugs, a street survey was conducted to understand where people purchase their anti-malarial drugs. RESULTS: A total of 432 samples were purchased from 41 pharmacies in 11 cities/towns in Gabon. The prevalence of poor-quality anti-malarial drugs was 0.5% (95% CI 0.08-1.84%). Two out of 432 samples failed the MiniLab(®) semi-quantitative TLC test, of which a suspected artemether-lumefantrine (AL) sample was classified as falsified and one sulfadoxine-pyrimethamine (SP) sample as substandard. High performance liquid chromatography with ultraviolet photo diode array detection analysis confirmed the absence of APIs in the AL sample, and showed that the SP sample did contain the stated APIs but the amount was half the stated dose. Of the people interviewed, 92% (187/203) purchased their anti-malarial drugs at a pharmacy. CONCLUSION: Using the GPHF Minilab(®), the prevalence of poor-quality anti-malarial drugs is far lower than anticipated. The findings emphasize the need for randomized and robust sampling methods in order to collect representative data on anti-malarial drug quality. TRIAL REGISTRATION: NTR4341 (Dutch Trial Registry).


Subject(s)
Antimalarials/analysis , Pharmacies , Antimalarials/standards , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Gabon , Quality Control
18.
Clin Infect Dis ; 60(4): 612-26, 2015 Feb 15.
Article in English | MEDLINE | ID: mdl-25344542

ABSTRACT

Human immunodeficiency virus (HIV) and sickle cell disease (SCD) are regarded as endemic in overlapping geographic areas; however, for most countries only scarce data on the interaction between HIV and SCD and disease burden exist. HIV prevalence in SCD patients varies between 0% and 11.5% in published studies. SCD has been suggested to reduce disease progression of HIV into AIDS. Various interactions of antiretroviral therapy with SCD exist. Both SCD and HIV act as common risk factors for stroke, avascular necrosis, severe splenic dysfunction, pulmonary arterial hypertension, and sepsis, which may result in synergistic increase in risk of developing these diseases. No treatment guidelines regarding SCD with HIV coinfection were identified. Available evidence is mainly based on small clinical studies, thus making strong recommendations difficult. An increased effort to elucidate the precise interactions is warranted to better understand both diseases and effect more adequate treatment approaches, especially in view of their geographical coprevalence.


Subject(s)
Anemia, Sickle Cell/complications , HIV Infections/complications , Africa/epidemiology , Anemia, Sickle Cell/epidemiology , Antiretroviral Therapy, Highly Active , Cohort Studies , Disease Progression , HIV Infections/drug therapy , HIV Infections/epidemiology , Humans , Hypertension, Pulmonary , Osteonecrosis/etiology , Prevalence , Risk Factors , Sepsis/etiology , Stroke/etiology
19.
Malar J ; 13: 463, 2014 Nov 26.
Article in English | MEDLINE | ID: mdl-25428624

ABSTRACT

BACKGROUND: Artemisinin combination therapy (ACT) is recommended as first-line treatment for uncomplicated Plasmodium falciparum malaria, whereas chloroquine is still commonly used for the treatment of non-falciparum species (Plasmodium vivax, Plasmodium ovale and Plasmodium malariae). A more simplified, more uniform treatment approach across all malaria species is worthwhile to be considered both in endemic areas and for malaria as an imported condition alike. METHODS: A PROSPERO-registered systematic review to determine the efficacy and safety of ACT for the treatment of non-falciparum malaria was conducted, following PRISMA guidelines. Without language restrictions, Medline/PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, LILACS, Biosis Previews and the African Index Medicus were searched for studies published up to November 2014. RESULTS: The literature search identified 986 reports; 40 publications were found eligible for inclusion, all of them on non-falciparum malaria in endemic areas. Most evidence was available for P. vivax (n = 35). Five clinical trials in total were identified evaluating ACT for P. ovale, P. malariae and Plasmodium knowlesi. Most ACT presentations have high efficacy against P. vivax parasites; artemisinin-based combinations have shorter parasite and fever clearance times compared to chloroquine. ACT is as effective as chloroquine in preventing recurrent parasitaemia before day 28. Artemisinin-based combinations with long half-lives show significantly fewer recurrent parasitaemia up to day 63. The limited evidence available supports both the use of chloroquine and an ACT for P. ovale and P. malariae. ACT seems to be preferable for optimal treatment of P. knowlesi. CONCLUSION: ACT is at least equivalent to chloroquine in effectively treating non-falciparum malaria. These findings may facilitate development of simplified protocols for treating all forms of malaria with ACT, including returning travellers. Obtaining comprehensive efficacy and safety data on ACT use for non-falciparum species particularly for P. ovale, P. malariae and P. knowlesi should be a research priority. TRIAL REGISTRATION: CRD42014009103.


Subject(s)
Antimalarials/adverse effects , Antimalarials/therapeutic use , Artemisinins/adverse effects , Artemisinins/therapeutic use , Malaria/drug therapy , Drug Therapy, Combination/adverse effects , Drug Therapy, Combination/methods , Drug-Related Side Effects and Adverse Reactions/epidemiology , Drug-Related Side Effects and Adverse Reactions/pathology , Humans , Treatment Outcome
20.
Int J Infect Dis ; 28: 47-64, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25197035

ABSTRACT

BACKGROUND: Leptospirosis is an emerging zoonotic infection worldwide, possibly due to climate change and demographic shifts. It is regarded as endemic in Sub-Saharan Africa; however, for most countries scarce epidemiological data, if any, exist. The primary objectives were to describe the prevalence of leptospirosis in countries in Sub-Saharan Africa, and to develop options for prevention and control in the future. METHODS: A systematic review was conducted to determine the prevalence of leptospirosis in Sub-Saharan Africa; the PRISMA guidelines were followed. Medline/PubMed, Embase, The Cochrane Library, Web of Science, BIOSIS Previews, the African Index Medicus, AJOL, and Google Scholar were searched. RESULTS: Information about the prevalence and incidence of leptospirosis in humans is available, but remains scarce for many countries. Data are unavailable or outdated for many countries, particularly those in Central Africa. Most data are available from animals, probably due to the economic losses caused by leptospirosis in livestock. In humans, leptospirosis is an important cause of febrile illness in Sub-Saharan Africa. It concerns numerous serogroups, harboured by many different animal carriers. DISCUSSION: A wide variety of data was identified. Prevalence rates vary throughout the continent and more research, especially in humans, is needed to reliably gauge the extent of the problem. Preventive measures need to be reconsidered to control outbreaks in the future.


Subject(s)
Leptospirosis/epidemiology , Africa South of the Sahara/epidemiology , Animals , Humans , Incidence , Leptospirosis/diagnosis , Prevalence , Zoonoses/epidemiology
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