Malaria and typhoid fever among patients presenting with febrile illnesses in Ga West Municipality, Ghana

BACKGROUND

Clinicians in areas where malaria and typhoid fever are co-endemic often treat infected patients irrationally, which may lead to the emergence of drug resistance and extra cost to patients. This study determined the proportion of febrile conditions attributable to either malaria and/or typhoid fever and the susceptibility patterns of Salmonella spp. isolates to commonly used antimicrobial agents in Ghana.

METHODS

One hundred and fifty-seven (157) febrile patients attending the Ga West Municipal Hospital, Ghana, from February to May 2017 were sampled. Blood samples were collected for cultivation of pathogenic bacteria and the susceptibility of the Salmonella isolates to antimicrobial agents was performed using the Kirby-Bauer disk diffusion method with antibiotic discs on Müller Hinton agar plates. For each sample, conventional Widal test for the detection of Salmonella spp was done as well as blood film preparation for detection of Plasmodium spp. Data on the socio-demographic and clinical characteristics of the study participants were collected using an android technology software kobo-collect by interview.

RESULTS

Of the total number of patients aged 2-37 years (median age = 6 years, IQR 3-11), 82 (52.2%) were females. The proportion of febrile patients with falciparum malaria was 57/157 (36.3%), while Salmonella typhi O and H antigens were detected in 23/157 (14.6%) of the samples. The detection rate of Salmonella spp in febrile patients was 10/157 (6.4%). Malaria and typhoid fever coinfection using Widal test and blood culture was 9 (5.7%) and 3 (1.9%), respectively. The isolates were highly susceptible to cefotaxime, ceftriaxone, ciprofloxacin, and amikacin but resistant to ampicillin, tetracycline, co-trimoxazole, gentamicin, cefuroxime, chloramphenicol, and meropenem.

CONCLUSION

Plasmodium falciparum and Salmonella spp coinfections were only up to 1.9%, while malaria and typhoid fever, individually, were responsible for 36.3% and 6.4%, respectively. Treatment of febrile conditions must be based on laboratory findings in order not to expose patients to unnecessary side effects of antibiotics and reduce the emergence and spread of drug resistance against antibiotics.

Utilization of 18s ribosomal RNA LAMP for detecting Plasmodium falciparum in microscopy and rapid diagnostic test negative patients

In this study, Plasmodium falciparum was detected in patients that were declared negative for malaria microscopy and rapid diagnostic test kit (mRDT), using Plasmodium 18s rRNA loop-mediated isothermal amplification (LAMP) technique. The main aim of this study was to assess the usefulness of LAMP assay for detecting pre-clinical malaria, when microscopy and mRDT were less sensitive. DNA was obtained from 100 μL of whole blood using the boil and spin method. Subsequently, the Plasmodium 18s rRNA LAMP assay was performed to amplify the specific Plasmodium 18s rRNA gene. Microscopy and mRDT negative samples [697/2223 (31.2%)] were used for this study. Compared to frequencies obtained for the other demographic variables, most of the patients were < 6 years (37.7%), females (59.0%), peri-urban dwellers (39.0%) and patients that sought outpatient department services (39.3%). Overall, the prevalence of Plasmodium 18s rRNA was 17.5%. when stratified by study variables, Plasmodium 18s rRNA LAMP positivity was higher in patients over 30 years [58/122 (54.2%)], males [69/122 (56.5%)], rural dwellers [69/122 (56.5%)] and patients that sought OPD services [68/122 (55.7%)]. The risk of being infected with Plasmodium when routine tests were negative was higher in 15-30-year group (OR = 3.03, 95% CI: 1.6-5.8, p = 0.0007), patients > 30 years (OR = 15.2, 95% CI: 8.3-27.7, p<0.001), males (OR = 2.1, 95% CI: 1.4-3.2, p = 0.0002) and rural dwellers (OR = 2.2, 95% CI:1.4-3.6, p = 0.0009). However, risk was lower in post-natal children (OR = 0.3, 95% CI: 0.18-0.51, p<0.001). Majority (81.5%) of the infected patients presented with headache, herpes labialis, diarrhea and vomiting. We demonstrated the lack of sensitivities of microscopy and mRDT for one-time diagnosis of malaria. Therefore, it is essential to utilize a sensitive technique such as Plasmodium 18s rRNA LAMP to increase the detection rate of Plasmodium infection.

Effect of Asymptomatic Plasmodium falciparum Parasitaemia on Platelets Thrombogenicity in Blood Donors

Currently, blood donors in Ghana are not screened for malaria parasites. Therefore, this study assessed platelet thrombogenicity in blood donors infected asymptomatically with Plasmodium falciparum and the relationship between tumour necrosis factor alpha (TNF-α), 8-iso-prostaglandin F2α oxidative stress biomarker (8-iso-PG2α), C-reactive protein (hs-CRP) and D-dimer, and platelet thrombogenes levels. Haematology analyser was used to enumerate platelet count and platelet indices in 80 P. falciparum infected blood donors and 160 matched non-infected controls. Replicate serum levels of von Willebrand Factor (vWF), platelet factor 4 (PF4), P-selectin thrombogenic factors as well as TNF-α and 8-iso-PG2α were determined using enzyme immuno-assay while high sensitive hs-CRP and D-dimer concentrations were determined by fluorescent immunoassay. The geometric mean of parasite density in malaria infected donors was 1784 parasites/µL (505-2478 parasites/µL). This led to significant increase in the mean levels of 8-iso-PG2α, hs-CRP, TNF-α and D-dimer. However, PF4, P-selectin were significantly lower in infected donors while vWF levels did not differ significantly among the groups even though lower levels were observed in the infected donors. Significant direct relationship existed between both P-selectin and PF4 and platelet count, and plateletcrit and platelet large cell ratio whereas these thrombogenic factors varied inversely to 8-iso-PG2α, TNF-α and hs-CRP. Relative thrombocytopaenia was associated with significant reduction in P-selectin and platelet factor 4 levels together with increased 8-iso-PG2α, hs-CRP, TNF-α and D-dimer levels. Taken together, it is recommended that all P. falciparum infected blood donors should be deferred.

Characterization of putative drug resistant biomarkers in Plasmodium falciparum isolated from Ghanaian blood donors

BACKGROUND

Plasmodium falciparum parasites, which could harbour anti-malaria drug resistance genes, are commonly detected in blood donors in malaria-endemic areas. Notwithstanding, anti-malaria drug resistant biomarkers have not been characterized in blood donors with asymptomatic P. falciparum infection.

METHODS

A total of 771 blood donors were selected from five districts in the Greater Accra Region, Ghana. Each donor sample was screened with malaria rapid diagnostic test (RDT) kit and parasitaemia quantified microscopically. Dried blood spots from malaria positive samples were genotyped for P. falciparum chloroquine resistance transporter (Pfcrt), P. falciparum multi-drug resistance (Pfmdr1), P. falciparum dihydropteroate-synthetase (Pfdhps), P. falciparum dihydrofolate-reductase (Pfdhfr) and Kelch 13 propeller domain on chromosome 13 (Kelch 13) genes.

RESULTS

Of the 771 blood donors, 91 (11.8%) were positive by RDT. Analysis of sequence reads indicated successful genotyping of Pfcrt, Pfmdr1, Pfdhfr, Pfdhps and Kelch 13 genes in 84.6, 81.3, 86.8, 86.9 and 92.3% of the isolates respectively. Overall, 21 different mutant haplotypes were identified in 69 isolates (75.8%). In Pfcrt, CVIET haplotype was observed in 11.6% samples while in Pfmdr1, triple mutation (resulting in YFN haplotype) was detected in 8.1% of isolates. In Pfdhfr gene, triple mutation resulting in IRNI haplotype and in Pfdhps gene, quintuple mutation resulting in AGESS haplotype was identified in 17.7% parasite isolates. Finally, five non-synonymous Kelch 13 alleles were detected; C580Y (3.6%), P615L (4.8%), A578S (4.8%), I543V (2.4%) and A676S (1.2%) were detected.

CONCLUSION

Results obtained in this study indicated various frequencies of mutant alleles in Pfcrt, Pfmdr1, Pfdhfr, Pfdhps and Kelch 13 genes from P. falciparum infected blood donors. These alleles could reduce the efficacy of standard malaria treatment in transfusion-transmitted malaria cases. Incorporating malaria screening into donor screening protocol to defer infected donors is therefore recommended.

The prevalence of hepatitis B virus E antigen among Ghanaian blood donors

Hepatitis B viral infection is an important clinical problem due to its worldwide distribution and potential of adverse sequelae, including hepatocellular carcinoma (HCC). We studied the prevalence of hepatitis B virus ‘e’ antigen (HBeAg) among individuals determined to be hepatitis B virus (HBV) surface antigen-positive and analyzed the gender/age category associated with more active HBV infection and whether alteration in the levels of alanine aminotransferase could be associated with HBeAg positivity. A total of 150 prospective blood donors who tested positive for hepatitis B surface antigen (HBsAg) at the blood transfusion center of the Komfo Anokye Teaching Hosptital (KATH), Kumasi were randomly selected for the study. The serum samples were further tested for HBsAg and HBeAg using a lateral flow immunochromatographic assay. Twenty (20) individuals were found to be HBeAg-positive giving an overall prevalence of 13.3%, of which 18 (15.5%) were males and 2 (5.9%) were females. Our results also revealed that the prevalence of HBeAg was higher in patients between the age group of 10-20 years and appeared to decrease with increase in age. There was no statistical difference between the HBeAg positive and negative individuals with respect to alanine aminotransferase (ALT) levels. We show for the first time that approximately 1/10 of HBV-infected individuals are HBeAg positive in the Ashanti Region of Ghana, suggestive of active viral replication and liver-cell infectivity thereby contributing to an increased HBV-transmission pool within the Ghanaian population.