Putative molecular markers of Plasmodium falciparum resistance to antimalarial drugs in malaria parasites from Ghana.

Introduction: Antimalarial drugs including artemisinin-based combination therapy (ACT) regimens and sulphadoxine-pyrimethamine (SP) are used in Ghana for malaria therapeutics and prophylaxis respectively. The genetic basis of Plasmodium falciparum development of drug resistance involves single nucleotide polymorphisms in genes encoding proteins for multiple cellular and metabolic processes. The prevalence of single nucleotide polymorphisms in nine P. falciparum genes linked to ACT and SP resistance in the malaria parasite population was determined. Methods: Archived filter paper blood blot samples from patients aged 9 years and below with uncomplicated malaria reporting at 10 sentinel sites located in three ecological zones for the Malaria Therapeutic Efficacy Studies were used. The samples used were collected from 2007-2018 malaria transmission seasons and mutations in the genes were detected using PCR and Sanger sequencing. Results: In all 1,142 samples were used for the study. For falcipain-2 gene (pffp2), Sanger sequencing was successful for 872 samples and were further analysed. The prevalence of the mutants was 45% (392/872) with pffp2 markers V51I and S59F occurring in 15.0% (128/872) and 3.0% (26/872) of the samples respectively. Prevalence of other P. falciparum gene mutations: coronin (pfcoronin) was 44.8% (37/90); cysteine desulfurase (pfnfs) was 73.9% (68/92); apicoplast ribosomal protein S10 (pfarps10) was 36.8% (35/95); ferredoxin (pffd) was 8.8% (8/91); multidrug resistance protein-1 (pfmrp1) was 95.2.0% (80/84); multidrug resistance protein-2 (pfmrp2) was 91.4% (32/35); dihydrofolate reductase (pfdhfr) was 99.0% (84/85); dihydropteroate synthase (pfdhps) was 72% (68/95). Discussion: The observation of numerous mutations in these genes of interest in the Ghanaian isolates, some of which have been implicated in delayed parasite clearance is of great interest. The presence of these genotypes may account for the decline in the efficacies of ACT regimens being used to treat uncomplicated malaria in the country. The need for continuous monitoring of these genetic markers to give first-hand information on parasite susceptibility to antimalarial drugs to inform policy makers and stakeholders in malaria elimination in the country is further discussed.

Novel pfk13 polymorphisms in Plasmodium falciparum population in Ghana.

The molecular determinants of Plasmodium falciparum artemisinin resistance are the single nucleotide polymorphisms in the parasite's kelch propeller domain, pfk13. Validated and candidate markers are under surveillance in malaria endemic countries using artemisinin-based combination therapy. However, pfk13 mutations which may confer parasite artemisinin resistance in Africa remains elusive. It has therefore become imperative to report all observed pfk13 gene polymorphisms in malaria therapeutic efficacy studies for functional characterization. We herein report all novel pfk13 mutations observed only in the Ghanaian parasite population. In all, 977 archived samples from children aged 12 years and below with uncomplicated malaria from 2007 to 2017 were used. PCR/Sanger sequencing analysis revealed 78% (763/977) of the samples analyzed were wild type (WT) for pfk13 gene. Of the 214 (22%) mutants, 78 were novel mutations observed only in Ghana. The novel SNPs include R404G, P413H, N458D/H/I, C473W/S, R529I, M579T/Y, C580R/V, D584L, N585H/I, Q661G/L. Some of the mutations were sites and ecological zones specific. There was low nucleotide diversity and purifying selection at the pfk13 locus in Ghanaian parasite population. With increasing drug pressure and its consequent parasite resistance, documenting these mutations as baseline data is crucial for future molecular surveillance of P. falciparum resistance to artemisinin in Ghana.

Evaluation of hepatic and kidney dysfunction among newly diagnosed HIV patients with viral hepatitis infection in Cape Coast, Ghana.

OBJECTIVE: HIV positive individuals infected with viral hepatitis B (HBV) or C (HCV) are at an increased risk of progression to kidney and liver failures. Therefore, prior to initiation of antiretroviral therapy, early diagnosis and initiation of appropriate treatment protocols are imperative for co-infected individuals. This study evaluated the prevalence of HBV and HCV, and extent of liver and renal dysfunction among 90 newly diagnosed HIV patients attending the Cape Coast Teaching Hospital HIV clinic. RESULTS: Levels of alanine aminotransferase, aspartate-platelet ratio index and estimated glomerular filtration rate were used respectively to diagnose hepatotoxicity, liver fibrosis and chronic kidney disease (CKD). Association analyses were evaluated by Pearson's Chi-square test or Fisher's exact test and considered significant at p < 0.05. Using rapid diagnostic tests, 75.6% (n = 68) had HIV1 mono-infection, 24.4% (n = 22) had HIV1/HBV co-infection while 0.0% (n = 0) had HIV1/HCV co-infection. The prevalence of hepatotoxicity, liver fibrosis, and CKD were 7.8% (n = 7), 2.2% (n = 2), and 15.5% (n = 14) respectively. Similar proportions of HIV1/HBV and HIV1 were diagnosed with liver fibrosis (p = 0.431). In relation to hepatotoxicity Grade, a high proportion of HIV1/HBV were diagnosed with Grade 2 (p = 0.042). Also, severely reduced kidney function (CKD stage 4) was observed in only HIV1/HBV (n = 2, 9.1%, p = 0.053).