Accuracy of a Plasmodium falciparum specific histidine-rich protein 2 rapid diagnostic test in the context of the presence of non-malaria fevers, prior anti-malarial use and seasonal malaria transmission

Abstract

BackgroundIt remains challenging to distinguish malaria from other fever causing infections, as a positive rapid diagnostic test does not always signify a true active malaria infection. This study was designed to determine the influence of other causes of fever, prior anti-malarial treatment, and a possible seasonality of the performance of a PfHRP2 RDT for the diagnosis of malaria in children under-5 years of age living in a malaria endemic area.MethodsA prospective etiology study was conducted in 2015 among febrile children under 5 years of age in Burkina Faso. In order to assess the influence of other febrile illnesses, prior treatment and seasonality on the performance of a PfHRP2 RDT in diagnosing malaria, the RDT results were compared with the gold standard (expert microscopic diagnosis of Plasmodium falciparum) and test results were analysed by assuming that prior anti-malarial use and bacterial/viral infection status would have been known prior to testing. To assess bacterial and viral infection status blood, urine and stool samples were analysed.ResultsIn total 683 blood samples were analysed with microscopy and RDT-PfHRP2. Plasmodium falciparum malaria was diagnosed in 49.8% (340/683) by microscopy compared to 69.5% (475/683) by RDT-PfHRP2. The RDT-PfHRP2 reported 29.7% (141/475) false positive results and 1.8% (6/340) false negative cases. The RDT-PfHRP2 had a high sensitivity (98.2%) and negative predictive value (97.1%), but a low specificity (58.9%) and positive predictive value (70.3%). Almost 50% of the alternative cause of fever were diagnosed by laboratory testing in the RDT false positive malaria group.ConclusionsThe use of a malaria RDT-PfHRP2 in a malaria endemic area may cause misdiagnosis of the actual cause of fever due to false positive test results. The development of a practical diagnostic tool to screen for other causes of fever in malaria endemic areas is required to save lives.

Prevalence of Asymptomatic Malaria among Children in the Tamale Metropolis: How Does the PfHRP2 CareStart™ RDT Perform against Microscopy?

“…With regards to PPV and NPV, it was observed that RDT exhibited an almost excellent NPV with a meagre PPV. e NPV of the RDT observed by Kiemde et al [25] and Ilombe et al [36] is as good as that in this study, but whilst the PPV in their reports is likewise lower, it is 2-4 folds higher than that in the current study. e results of the current study however do not suggest that the PfHRP2 CareStart ™ RDT is of substandard, but rather re-echo the fact that at very low parasite density (far below the 200 parasites/μL minimum threshold as set by WHO) current batch of RDTs are not very useful and therefore the need for ultrasensitive RDT especially in areas where even microscopy is a challenge and PCR is simply impossible.…”

“…Also, these studies and that of Kwenti et al [35], much like this present study, reported RDT to have a rather high specificity than sensitivity. However, contrary to this finding, several other studies have reported higher sensitivity rather than specificity for RDT in asymptomatic individuals [25,[36][37][38]. With regards to PPV and NPV, it was observed that RDT exhibited an almost excellent NPV with a meagre PPV.…”

“…Nevertheless, in Myanmar, Huang et al [21] and Zaw et al [22] separately reported a higher parasite prevalence among asymptomatic males. Likewise, Kiemde et al [25] found asymptomatic malaria to be prevalent among males using both microscopy and RDT. In another study conducted in Ghana, asymptomatic Plasmodium infection was observed to be rather prevalent among females [24].…”

Implementation of a malaria rapid diagnostic test in a rural setting of Nanoro, Burkina Faso: from expectation to reality

“…In general, the specificity of the HRP2-based RDTs is being questioned particularly under low transmission conditions [20]. This is supported by one of previous studies conducted in the same study area in which a high prevalence of false positive RDT results was reported during the dry season (April–May; low transmission) [22]. However, the present study was mainly conducted during the rainy season (June–October; high transmission season) but still the number of false positive tests was almost twofold higher at the participating health facilities compared to the laboratory of CRUN.…”

<p>Optimal Approach and Strategies to Strengthen Pharmacovigilance in Sub-Saharan Africa: A Cohort Study of Patients Treated with First-Line Artemisinin-Based Combination Therapies in the Nanoro Health and Demographic Surveillance System, Burkina Faso</p>

“…In addition, with the increase in the number of concomitant medication prescriptions, the risk of occurrence of ADRs increased. This could be explained partly by the fact that during the period of high malaria transmission, the diagnosis of malaria episodes (with malaria RDTs) is more accurate 55 and therefore would improve the accuracy in the drug prescription for illness management (less prescription of concomitant therapy). At the same time, the rainy season coincides with the beginning of farming activities, and families usually move from their usual homeland to hamlets with limited geographical accessibility.…”