RESUMEN
Objectives: Malaria in pregnancy (MIP) is a major healthcare challenge in low-income countries with high malaria endemicity. Early but accurate diagnosis and appropriate treatment is the hallmark of preventing disease progression/adverse outcomes in the mother, foetus and neonates. We assessed the comparative diagnostic performance of Malaria Rapid Diagnostic Test (mRDT), microscopy and PCR for malaria diagnosis in pregnant women for early detection of asymptomatic malaria in pregnant women. Study design: Five hundred and twenty Pregnant women attending study clinics within Ikene and Remo North LGAs with gestational age between 16 and 29 weeks, willing and consented; were enrolled into the study. Blood samples collected via venepuncture were screened for malaria using microscopy, mRDTs kits, and PCR techniques on their first visit (V1) and at delivery. The parasite positivity rates, sensitivity and specificity were calculated and compared for each technique using PCR as the standard. Data was entered into REDCap® online database and analysis done using Stata and MedCalc®. Results and conclusions: Average age of enrolled women was 28.8 years and mean gestational age was 21.0 weeks. The parasite positivity rates were 4.3%, 8.8% and 25.0% for microscopy, mRDT and PCR at V1 and was 2.4%, 3.4% and 43.4% at delivery, respectively. Sensitivity for microscopy and mRDT was 11.2% and 30.3% respectively at V1, while specificity was 98.2% and 98.5%. At delivery, the sensitivity reduced to 1.6% and 4.9%; while specificity was 96.9% and 97.6% respectively. Only 2.3% cases correlated with all three diagnostic methods. Our data showed a decrease in sensitivity of the diagnostic methods as pregnancy progressed, which may be due to very low parasitaemia, but high specificity. Our study demonstrated a high rate of subpatent parasitaemia amongst pregnant women. This finding therefore raises the question of the effect of subpatent parasitaemia on the health of the mother and foetus.
RESUMEN
BACKGROUND: Malaria rapid diagnostic tests (mRDTs) are the preferred option for programmatic deployment. AIMS: There are numerous mRDTs on the Nigerian market and there is a need to guide practitioners on the relative performance of the commonly used brands of mRDT in Nigeria. SUBJECTS AND METHODS: The performance of three commonly used Histidine-Rich-Protein-2-based mRDTs (SD-Bioline™, Carestart™ and Paracheck-Pf™) against microscopy of Giemsa stained blood and polymerase chain reaction (PCR) was evaluated among 190 febrile under-5 children in Ibadan, Nigeria. We calculated the sensitivity, specificity, predictive values, accuracy, and agreements. RESULTS: There were 53.2% males. The prevalence of malaria parasite by microscopy was 46.8% and 57.9% by PCR. Malaria parasite detection by SD-Bioline™ was 60.5%, Carestart™: 60.0% and Paracheck-Pf™ 60.0%. Using microscopy as the gold standard, the sensitivities of SD-Bioline™, Carestart™ and Paracheck-Pf™ mRDT were 97.8%, 96.7% and 97.8% respectively while the specificities were 73.0%, 72.0% and 74.0% respectively. Using PCR as the gold standard, the sensitivity for both SD-Bioline™ and Paracheck-Pf™ was 85.5% and for CareStart was 84.6% while the specificity of SD-Bioline™, Carestart™, and Paracheck-Pf™ was 73.8%, 72.4%, and 75.0% respectively. The test accuracy was 81.0% for both SD-Bioline™ and Paracheck-Pf™ and 80.0% for Caresatrt™. The kappa coefficient of agreement between PCR and each of SD-Bioline™, Carestart, ParaCheck™ and microscopy was 0.597, 0.578, 0.609 and 0.739 respectively. CONCLUSION: The performance of the three mRDTs is a proof that any of the three is suitable for use in the diagnosis of malaria in the southwest of Nigeria.
