Anti-malaria prescription in pregnancy among general practitioners in Enugu state, south east Nigeria

Polymorphisms in Plasmodium falciparum chloroquine resistance transporter (Pfcrt) and multidrug-resistant gene 1 (Pfmdr-1) in Nigerian children 10 years post-adoption of artemisinin-based combination treatments

The emergence and spread of Plasmodium falciparum parasites resistant to artemisinin derivatives and their partners in southeastern Asia threatens malaria control and elimination efforts, and heightens the need for an alternative therapy. We have explored the distribution of P. falciparum chloroquine resistance transporter (Pfcrt) and multidrug-resistant gene 1 (Pfmdr-1) haplotypes 10 years following adoption of artemisinin-based combination therapies in a bid to investigate the possible re-emergence of Chloroquine-sensitive parasites in Nigeria, and investigated the effect of these P. falciparum haplotypes on treatment outcomes of patients treated with artemisinin-based combination therapies. A total of 271 children aged <5 years with uncomplicated falciparum malaria were included in this study. Polymorphisms on codons 72-76 of the Pfcrt gene and codon 86 and 184 of Pfmdr-1 were determined using the high resolution melting assay. Of 240 (88.6%) samples successfully genotyped with HRM for Pfcrt, wildtype C72M74N75K76 (42.9%) and mutant C72I74E75T76 (53.8%) were observed. Also, wildtype N86Y184 (62.9%) and mutant N86F184 (21.1%), Y86Y184 (6.4%), and Y86F184 (0.4%) haplotypes of Pfmdr-1 were observed. Measures of responsiveness to ACTs were similar in children infected with P. falciparum crt haplotypes (C72I74E75T76 and C72M74N75K76) and major mdr-1 haplotypes (N86Y184, N86F184 and Y86Y184). Despite a 10 year gap since the malaria treatment policy changed to ACTs, over 50% of the P. falciparum parasites investigated in this study harboured the Chloroquine-resistant C72I74E75T76 haplotype, however this did not compromise the efficacy of artemisinin-based combination therapies. Should complete artemisinin resistance emerge from or spread to Nigeria, chloroquine might not be a good alternative therapy.

Medication use among pregnant women at a secondary health institution: utilisation patterns and predictors of quantity

BACKGROUND

Despite the lack of adequate studies on the safety of drugs in pregnancy, surprisingly, available evidence shows that pregnant women still take large number of drugs.

OBJECTIVES

The study aim was to determine drug utilization pattern and predictors of number of medications used by pregnant women.

METHODS

This was a cross-sectional survey of 369 pregnant women attending a secondary health facility. Data were collected using interviewer-administered questionnaire. Descriptive and inferential statistics using the Chi-Square test were carried out with level of significance set at p<0.05.

RESULTS

Three hundred and sixty-nine women were interviewed. Their mean age was 27.7 years (SD± 4.78) and the mean number of pregnancies was 2.46 (SD± 1.34). On average, 2.62 medications were taken, with the lowest being 1 and the highest being 12 different medications during the course of pregnancy. Those who were on more than 2 medications were more likely to be older than 30 years, had lower education and with history of associated medical conditions. All participants were on one form of supplements or the other, nearly half had used antimalarials, 12.8%, 5.8% 2.4% were on antibiotics, anti-hypertensive and anti-retroviral medications respectively. All the medications prescribed were from category A, B, C, N, and none from category D and X.

CONCLUSION

Varieties of medications were used during the course of pregnancy among this population, however, most of these drugs were still within safety profile.

High multiple mutations of Plasmodium falciparum-resistant genotypes to sulphadoxine-pyrimethamine in Lagos, Nigeria

Background

Plasmodium falciparum-resistance to sulphadoxine-pyrimethamine (SP) has been largely reported among pregnant women. However, the profile of resistance markers to SP dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) in the general population are varied and not frequently monitored. Currently, SP is used as partner drug for artemisinin combination therapy (SP-artesunate) in some sub-Saharan African countries or as a prophylactic drug in intermittent preventive treatment of malaria during pregnancy and infants and in seasonal malaria chemoprevention (SMC). Profiling of P. falciparum-resistant genotypes to SP is dynamic and critical in providing data that would be useful for malaria control programmes. This study assessed the profile of dhfr and dhps genes genotypes among individuals with malaria in Lagos, Nigeria.

Methods

Molecular markers of SP resistance were identified by nested PCR and sequenced among malaria positive dried blood spots (DBS) that were collected from individuals attending health facilities from January 2013 to February 2014 and during community surveys from October 2010 to September 2011 across different Local Government Areas of Lagos State, Nigeria.

Results

A total of 242 and 167 samples were sequenced for dhfr and dhps, respectively. Sequence analysis of dhfr showed that 95.5% (231/242), 96.3% (233/242) and 96.7% (234/242) of the samples had N51I, C59R and S108N mutant alleles, respectively. The prevalence of dhps mutation at codons A437G, A613S, S436A, A581G, I431V and K540E were 95.8% (160/167), 41.9% (70/167), 41.3% (69/167), 31.1% (52/167), 25.1% (42/167), and 1.2% (2/167) respectively. The prevalence of triple mutations (CIRNI) in dhfr was 93.8% and 44.3% for the single dhps haplotype mutation (SGKAA). Partial SP-resistance due to quadruple dhfr-dhps haplotype mutations (CIRNI-SGKAA) and octuple haplotype mutations (CIRNI-VAGKGS) with rate of 42.6% and 22.0%, respectively has been reported.

Conclusions

There was increased prevalence in dhfr triple haplotype mutations when compared with previous reports in the same environment but aligned with high prevalence in other locations in Nigeria and other countries in Africa. Also, high prevalence of dhfr and dhps mutant alleles occurred in the study areas in Lagos, Nigeria five to eight years after the introduction of artemisinin combination therapy underscores the need for continuous monitoring.

Use of Intermittent Preventive Treatment among Pregnant Women in Sub-Saharan Africa: Evidence from Malaria Indicator Surveys

Uptake of intermittent preventive therapy in pregnancy (IPTp) with sulfadoxine-pyrimethamine (IPTp-SP) is a clinically-proven method to prevent the adverse outcomes of malaria in pregnancy (MiP) for the mother, her foetus, and the neonates. The majority of countries in sub-Saharan Africa have introduced IPTp policies for pregnant women during the past decade. Nonetheless, progress towards improving IPTp coverage remains dismal, with widespread regional and socioeconomic disparities in the utilisation of this highly cost-effective service. In the present study, our main objective was to measure the prevalence of IPTp uptake in selected malaria-endemic countries in sub-Saharan Africa, and to investigate the patterns of IPTp uptake among different educational and wealth categories adjusted for relevant sociodemographic factors. For this study, cross-sectional data on 18,603 women aged between 15 and 49 years were collected from the Malaria Indicator Surveys (MIS) conducted in Burkina Faso, Ghana, Mali, Malawi, Kenya, Nigeria, Sierra Leone, and Uganda. The outcome variable was taking three doses of IPTp-SP in the last pregnancy, defined as adequate by the WHO. According to the analysis, the overall prevalence of taking three doses of IPTp-SP in the latest pregnancy was 29.5% (95% CI = 28.2–30.5), with the prevalence being highest for Ghana (60%, 95% CI = 57.1–62.8), followed by Kenya (37%, 95% CI = 35.3–39.2) and Sierra Leone (31%, 95% CI = 29.2–33.4). Women from non-poor households (richer—20.7%, middle—21.2%, richest—18.1%) had a slightly higher proportion of taking three doses of IPTp-SP compared with those from poorest (19.0%) and poorer (21.1%) households. Regression analysis revealed an inverse association between uptake of IPTp-SP and educational level. With regard to wealth status, compared with women living in the richest households, those in the poorest, poorer, middle, and richer households had significantly higher odds of not taking at least three doses of IPTp-SP during their last pregnancy. The present study concludes that the prevalence of IPTp-SP is still alarmingly low and is significantly associated with individual education and household wealth gradient. Apart from the key finding of socioeconomic disparities within countries, were the between-country variations that should be regarded as a marker of inadequate policy and healthcare system performance in the respective countries. More in-depth and longitudinal studies are required to understand the barriers to, and preferences of, using IPTp-SP among women from different socioeconomic backgrounds.

Treatment of uncomplicated and severe malaria during pregnancy

Over the past 10 years, the available evidence on the treatment of malaria during pregnancy has increased substantially. Owing to their relative ease of use, good sensitivity and specificity, histidine rich protein 2 based rapid diagnostic tests are appropriate for symptomatic pregnant women; however, such tests are less appropriate for systematic screening because they will not detect an important proportion of infections among asymptomatic women. The effect of pregnancy on the pharmacokinetics of antimalarial drugs varies greatly between studies and class of antimalarial drugs, emphasising the need for prospective studies in pregnant and non-pregnant women. For the treatment of malaria during the first trimester, international guidelines are being reviewed by WHO. For the second and third trimester of pregnancy, results from several trials have confirmed that artemisinin-based combination treatments are safe and efficacious, although tolerability and efficacy might vary by treatment. It is now essential to translate such evidence into policies and clinical practice that benefit pregnant women in countries where malaria is endemic. Access to parasitological diagnosis or appropriate antimalarial treatment remains low in many countries and regions. Therefore, there is a pressing need for research to identify quality improvement interventions targeting pregnant women and health providers. In addition, efficient and practical systems for pharmacovigilance are needed to further expand knowledge on the safety of antimalarial drugs, particularly in the first trimester of pregnancy.

Antimalarial treatment patterns among pregnant women attending antenatal care clinics in south east Nigeria and the future implications

BACKGROUND

Prompt and effective treatment of malaria in pregnancy in accordance with recommended guidelines is essential to help prevent adverse events among pregnant mothers and the foetus.

AIM

The aim of this study was to assess current prescribing of antimalarial medicines in pregnancy against policy guidelines in south east Nigeria to provide future guidance.

METHODS

A review of prescription records of pregnant women treated for malaria over a 6-month period between August 2013 and January 2014 was carried out to assess the prescribing patterns for both the prevention and treatment of malaria in each trimester and analyzed for conformity to recommended guidelines.

RESULTS

Among 859 antenatal records reviewed, the majority (83.2%) were in the second and third trimesters. Artemisinin-based combination therapies (40.9%) and sulfadoxine-pyrimethamine (37.5%) were the most prescribed antimalarial medicines for both treatment and prophylaxis (prevention), respectively, in all trimesters. Overall, 68.5% of the prescriptions conformed to guideline recommendations, with the prescriptions for non-recommended drugs occurring most often in the first trimester. In the second and three trimesters, up to 79.9% of pregnant women received appropriate medicines for both treatment and prevention of malaria, with artemether-lumefantrine the most prescribed regimen.

CONCLUSION

Current practice indicates greater conformity with guidelines particularly in the second and three trimesters vs previous studies. However, there are still concerns with prescribing practices in the first trimester, especially in private health facilities. This needs addressing.

Molecular determinants of sulfadoxine-pyrimethamine resistance in Plasmodium falciparum in Nigeria and the regional emergence of dhps 431V

There are few published reports of mutations in dihydropteroate synthetase (dhps) and dihydrofolate reductase (dhfr) genes in P. falciparum populations in Nigeria, but one previous study has recorded a novel dhps mutation at codon 431 among infections imported to the United Kingdom from Nigeria. To assess how widespread this mutation is among parasites in different parts of the country and consequently fill the gap in sulfadoxine-pyrimethamine (SP) resistance data in Nigeria, we retrospectively analysed 1000 filter paper blood spots collected in surveys of pregnant women and children with uncomplicated falciparum malaria between 2003 and 2015 from four sites in the south and north.

Genomic DNA was extracted from filter paper blood spots and placental impressions. Point mutations at codons 16, 50, 51, 59, 108, 140 and 164 of the dhfr gene and codons 431, 436, 437, 540, 581 and 613 of the dhps gene were evaluated by nested PCR amplification followed by direct sequencing.

The distribution of the dhps-431V mutation was widespread throughout Nigeria with the highest prevalence in Enugu (46%). In Ibadan where we had sequential sampling, its prevalence increased from 0% to 6.5% between 2003 and 2008. Although there were various combinations of dhps mutations with 431V, the combination 431V + 436A + 437G+581G+613S was the most common.

All these observations support the view that dhps-431V is on the increase. In addition, P. falciparum DHPS crystal structure modelling shows that the change from Isoleucine to Valine (dhps-431V) could alter the effects of both S436A/F and A437G, which closely follow the 2nd β-strand. Consequently, it is now a research priority to assess the implications of dhps-VAGKGS mutant haplotype on continuing use of SP in seasonal malaria chemoprevention (SMC) and intermittent preventive treatment in pregnancy (IPTp). Our data also provides surveillance data for SP resistance markers in Nigeria between 2003 and 2015.

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We present data on dhps and dhfr mutations in P. falciparum populations in Nigeria.

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Increased prevalence of I431V mutation was seen between 2003 and 2015 from 0 to 36%.

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The 431V + 436A + 437G + 581G + 613S was the most common with dhps-431V mutation.

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Crystal structure modelling of Pf DHPS shows that 431Vcould alter S436A and A437G.