Vivax Malaria Patients Research Articles

Screening and identification of potential novel biomarker for diagnosis of complicated Plasmodium vivax malaria

BackgroundIn the recent years Plasmodium vivax has been reported to cause severe infections associated with mortality. Clinical evaluation has limited accuracy for the early identification of the patients progressing towards the fatal condition. Researchers have tried to identify the serum and the plasma-based indicators of the severe malaria. Discovery of MicroRNA (miRNA) has opened up an era of identification of early biomarkers for various infectious and non-infectious diseases. MicroRNAs (miRNA) are the small non-coding RNA molecules of length 19–24 nts and are responsible for the regulation of the majority of human gene expressions at post transcriptional level.MethodsWe identified the differentially expressed miRNAs by microarray and validated the selected miRNAs by qRT-PCR. We assessed the diagnostic potential of these up-regulated miRNAs for complicated P. vivax malaria. Futher, the bioinformtic analysis was performed to construct protein–protein and mRNA–miRNA networks to identify highly regulated miRNA.ResultsIn the present study, utility of miRNA as potential biomarker of complicated P. vivax malaria was explored. A total of 276 miRNAs were found to be differentially expressed by miRNA microarray and out of which 5 miRNAs (hsa-miR-7977, hsa-miR-28-3p, hsa-miR-378-5p, hsa-miR-194-5p and hsa-miR-3667-5p) were found to be significantly up-regulated in complicated P. vivax malaria patients using qRT-PCR. The diagnostic potential of these 5 miRNAs were found to be significant with sensitivity and specificity of 60–71% and 69–81% respectively and area under curve (AUC) of 0.7 (p < 0.05). Moreover, in silico analysis of the common targets of up-regulated miRNAs revealed UBA52 and hsa-miR-7977 as majorly regulated hubs in the PPI and mRNA–miRNA networks, suggesting their putative role in complicated P. vivax malaria.ConclusionmiR-7977 might act as a potential biomarker for differentiating complicated P. vivax malaria from uncomplicated type. The elevated levels of miR-7977 may have a role to play in the disease pathology through UBA52 or TGF-beta signalling pathway.

A prospective comparative study of clinical profile and severity of plasmodium falciparum and plasmodium vivax in coastal Andhra Pradesh, India

Background: Plasmodium falciparum (P. falciparum) causes vital organ dysfunction. The manifestation of severe form of falciparum malaria includes cerebral malaria, acidosis, severe anaemia, renal failure, hypotension, shock, disseminated intravascular coagulation and convulsion. Death rate used to be high. But vivax malaria is not presented in severe form and there is tendency of recurrence. Present study has been designed to compare clinical profile and severity of P. falciparum and Plasmodium vivax (P. vivax) malaria in coastal district of Andhra Pradesh.Methods: Present study is a prospective comparative randomized observational study conducted in the depart of general medicine Rangaraya Medical College, Kakinada, Andhra Pradesh from February 2016 to May 2018. The study population include 260 patients diagnosed to have P. falciparum and P. vivax malaria and being admitted in the general medicine dept. Govt medical college Kakinada randomly selected based on exclusion and inclusion criteria.Results: Out of 172 Falciparum malaria patients’ anaemia was present in 39.53% patient and out of 88 P. vivax patients 43.18% patients have anaemia. Thrombocytopenia was present in 19.76% patients of falciparum malaria and 79.54% of P. vivax. Increased leucocyte count was seen in 29.65% P. falciparum and 4.54% P. vivax patients. Leukopenia was seen in 9.3% P. falciparum and 1.136% P. vivax patient. PT and APTT was increased in 12.79% patients of P. falciparum malaria and 6.8% patients of P. vivax malaria. Liver enzyme was elevated in 27.9% of P. falciparum patients and 47.72% patients of P. vivax patients. Raised serum urea and creatinine, was seen in 18.60% patients of P. falciparum and 18.18% patients of P. vivax malaria. Electrolyte imbalance was also found in both groups.Conclusions: - In present study number of falciparum malaria cases were more than vivax with male predominance. Hepatomegaly was more common falciparum, but splenomegaly was more common in vivax malaria patients. Anaemia and thrombocytopenia were more common in P. vivax malaria patients. Elevated liver enzyme was more common in P. vivax patients but elevated serum urea and creatinine was almost same in both groups. Except hepatic dysfunction all other complication was more in falciparum then vivax infection. Death was only marginally high in falciparum then vivax malaria patients.

Cross-species analysis of apical asparagine-rich protein of Plasmodium vivax and Plasmodium knowlesi

The Plasmodium falciparum apical asparagine (Asn)-rich protein (AARP) is one of malarial proteins, and it has been studied as a candidate of malaria subunit vaccine. Basic characterization of PvAARP has been performed with a focus on its immunogenicity and localization. In this study, we further analyzed the immunogenicity of PvAARP, focusing on the longevity of the antibody response, cross-species immunity and invasion inhibitory activity by using the primate malaria parasite Plasmodium knowlesi. We found that vivax malaria patient sera retained anti-PvAARP antibodies for at least one year without re-infection. Recombinant PvAARP protein was strongly recognized by knowlesi malaria patients. Antibody raised against the P. vivax and P. knowlesi AARP N-termini reacted with the apical side of the P. knowlesi merozoites and inhibited erythrocyte invasion by P. knowlesi in a concentration-dependent manner, thereby suggesting a cross-species nature of anti-PvAARP antibody against PkAARP. These results can be explained by B cell epitopes predicted in conserved surface-exposed regions of the AARP N-terminus in both species. The long-lived anti-PvAARP antibody response, cross-reactivity, and invasion inhibitory activity of anti-PvAARP support a critical role of AARP during the erythrocyte invasion and suggest that PvAARP induces long-lived cross-species protective immunity against P. vivax and P. knowlesi.

Distinct inflammatory profile underlies pathological increases in creatinine levels associated with Plasmodium vivax malaria clinical severity.

BackgroundAlthough Plasmodium vivax infection is a frequent cause of malaria worldwide, severe presentations have been more regularly described only in recent years. In this setting, despite clinical descriptions of multi-organ involvement, data associating it with kidney dysfunction are relatively scarce. Here, renal dysfunction is retrospectively analyzed in a large cohort of vivax malaria patients with an attempt to dissect its association with disease severity and mortality, and to determine the role of inflammation in its progression.MethodsA retrospective analysis of a databank containing 572 individuals from the Brazilian Amazon, including 179 patients with P. vivax monoinfection (161 symptomatic malaria, 12 severe non-lethal malaria, and 6 severe lethal disease) and 165 healthy controls, was performed. Data on levels of cytokines, chemokines, C-reactive protein (CRP), fibrinogen, creatinine, hepatic enzymes, bilirubin levels, free heme, and haptoglobin were analyzed to depict and compare profiles from patients per creatinine levels.ResultsElevated creatinine levels were found predominantly in women. Vivax malaria severity was highly associated with abnormal creatinine increases, and nonsurvivors presented the highest values of serum creatinine. Indication of kidney dysfunction was not associated with parasitemia levels. IFN-γ/IL-10 ratio and CRP values marked the immune biosignature of vivax malaria patients, and could distinguish subjects with elevated creatinine levels who did not survive from those who did. Patients with elevated serum creatinine or severe vivax malaria displayed indication of cholestasis. Biomarkers of hemolysis did not follow increases in serum creatinine.ConclusionThese findings reinforce the hypothesis that renal dysfunction is a key component in P. vivax malaria associated with clinical severity and mortality, possibly through intense inflammation and immune imbalance. Our study argues for systematic evaluation of kidney function as part of the clinical assessment in vivax malaria patients, and warrants additional studies in experimental models for further mechanism investigations.

CYP2D6 activity and the risk of recurrence of Plasmodium vivax malaria in the Brazilian Amazon: a prospective cohort study

BackgroundCYP2D6 pathway mediates the activation of primaquine into active metabolite(s) in hepatocytes. CYP2D6 is highly polymorphic, encoding CYP2D6 isoforms with normal, reduced, null or increased activity. It is hypothesized that Plasmodium vivax malaria patients with defective CYP2D6 function would be at increased risk for primaquine failure to prevent recurrence. The aim of this study was to investigate the association of CYP2D6 polymorphisms and inferred CYP2D6 phenotypes with malaria recurrence in patients from the Western Brazilian Amazon, following chloroquine/primaquine combined therapy.MethodsThe prospective cohort consisted of P. vivax malaria patients who were followed for 6 months after completion of the chloroquine/primaquine therapy. Recurrence was defined as one or more malaria episodes, 28–180 days after the initial episode. Genotyping for nine CYP2D6 SNPs and copy number variation was performed using TaqMan assays in a Fast 7500 Real-Time System. CYP2D6 star alleles (haplotypes), diplotypes and CYP2D6 phenotypes were inferred, and the activity score system was used to define the functionality of the CYP2D6 diplotypes. CYP2D6 activity scores (AS) were dichotomized at ≤ 1 (gPM, gIM and gNM-S phenotypes) and ≥ 1.5 (gNM-F and gUM phenotypes).ResultsGenotyping was successfully performed in 190 patients (44 with recurrence and 146 without recurrences). Recurrence incidence was higher in individuals presenting reduced activity CYP2D6 phenotypes (adjusted relative risk = 1.89, 95% CI 1.01–3.70; p = 0.049). Attributable risk and population attributable fraction were 11.5 and 9.9%, respectively. The time elapsed from the first P. vivax malaria episode until the recurrence did not differ between patients with AS of ≤ 1 versus ≥ 1.5 (p = 0.917).ConclusionsThe results suggest that CYP2D6 polymorphisms are associated with increased risk of recurrence of vivax malaria, following chloroquine–primaquine combined therapy. This association is interpreted as the result of reduced conversion of primaquine into its active metabolites in patients with reduced CYP2D6 enzymatic activity.

Genomic Analyses Reveal the Common Occurrence and Complexity of Plasmodium vivax Relapses in Cambodia.

ABSTRACTPlasmodium vivax parasites have a unique dormant stage that can cause relapses weeks or months after the initial infection. These dormant parasites are among the main challenges of vivax malaria control as they constitute a reservoir that is difficult to eliminate. Since field studies are confounded by reinfections and possible recrudescence of drug-resistant parasites, most analyses of P. vivax relapses have focused on travelers returning from regions of malaria endemicity. However, it is not clear whether these individuals accurately recapitulate the relapse patterns of repeatedly infected individuals residing in areas of endemicity. Here, we present analyses of vivax malaria patients enrolled in a tightly controlled field study in Cambodia. After antimalarial drug treatment was administered, we relocated 20 individuals to a nontransmission area and followed them for 60 days, with blood collection performed every second day. Our analyses reveal that 60% of the patients relapsed during the monitoring period. Using whole-genome sequencing and high-throughput genotyping, we showed that relapses in Cambodia are often polyclonal and that the relapsing parasites harbor various degrees of relatedness to the parasites present in the initial infection. Our analyses also showed that clone populations differed dynamically, with new clones emerging during the course of the relapsing infections. Overall, our study data show that it is possible to investigate the patterns, dynamics, and diversity of P. vivax relapses of individuals living in a region of malaria endemicity and reveal that P. vivax relapses are much more pervasive and complex than previously considered. (This study has been registered at ClinicalTrials.gov under registration no. NCT02118090.)

Glucose-6-Phosphate dehydrogenase deficiency genetic variation in vivax malaria patients from Thai-Myanmar and Thai-Malaysian border

Glucose-6-Phosphate dehydrogenase deficiency genetic variation in vivax malaria patients from Thai-Myanmar and Thai-Malaysian border

Are respiratory complications of Plasmodium vivax malaria an underestimated problem?

BackgroundRespiratory complications are uncommon, but often life-threatening features of Plasmodium vivax malaria. This study aimed to estimate the prevalence and lethality associated with such complications among P. vivax malaria patients in a tertiary hospital in the Western Brazilian Amazon, and to identify variables associated with severe respiratory complications, intensive care need and death. Medical records from 2009 to 2016 were reviewed aiming to identify all patients diagnosed with P. vivax malaria and respiratory complications. Prevalence, lethality and risk factors associated with WHO defined respiratory complications, intensive care need and death were assessed.ResultsA total of 587 vivax malaria patients were hospitalized during the study period. Thirty (5.1%) developed respiratory complications. Thirteen (43.3%) developed severe respiratory complications, intensive care was required for 12 (40%) patients and 5 (16.6%) died. On admission, anaemia and thrombocytopaenia were common findings, whereas fever was unusual. Patients presented different classes of parasitaemia and six were aparasitaemic on admission. Time to respiratory complications occurred after anti-malarials administration in 18 (60%) patients and progressed very rapidly. Seventeen patients (56.7%) had comorbidities and/or concomitant conditions, which were significantly associated to higher odds of developing severe respiratory complications, need for intensive care and death (p < 0.05).ConclusionRespiratory complications were shown to be associated with significant mortality in this population. Patients with comorbidities and/or concomitant conditions require special attention to avoid this potential life-threatening complication.

Malaria cases in Switzerland from 2005 to 2015 and recent rise of imported Plasmodium vivax malaria.

Reporting cases of malaria to the Federal Office of Public Health has been mandatory in Switzerland since 1974. We analysed notifications of imported confirmed malaria cases between 2005 and 2015 in Switzerland or Liechtenstein. Data for previously visited countries, nationality and reason for travelling were analysed. In contrast with the impressive drop of malaria cases reported worldwide since 2000, we found that the number of malaria cases imported yearly in Switzerland doubled in 2014 and 2015 compared to the average for the preceding decade. Since 2014, Plasmodium vivax infection represented 36% of all diagnosed malaria cases in Switzerland, compared to 11% in the decade leading to 2013. Most of the vivax malaria patients originated from the Horn of Africa, especially from Eritrea. This rise in cases was a consequence not only of an increase in the number of Eritrean refugees, but also their vivax malaria incidence rate, which jumped from 1-3‰ previously to 12‰ in 2014. This is a trend that is not matched by national statistics in Eritrea. An unreported increased incidence in the country of origin (Eritrea) might be the cause of the rise of Pv cases imported into Switzerland, but infections are also likely to occur along the harsh and long migration journey. This epidemiology highlights the need to register and use primaquine for the treatment of latent-phase P. vivax malaria in Switzerland, a medicine currently neither marketed nor systematically reimbursed. Moreover, general practitioners should be aware of this specific epidemiological situation in order to avoid misdiagnosis of febrile Eritreans even months after they reach Switzerland.

Plasma metabolomics reveals membrane lipids, aspartate/asparagine and nucleotide metabolism pathway differences associated with chloroquine resistance in Plasmodium vivax malaria.

BackgroundChloroquine (CQ) is the main anti-schizontocidal drug used in the treatment of uncomplicated malaria caused by Plasmodium vivax. Chloroquine resistant P. vivax (PvCR) malaria in the Western Pacific region, Asia and in the Americas indicates a need for biomarkers of resistance to improve therapy and enhance understanding of the mechanisms associated with PvCR. In this study, we compared plasma metabolic profiles of P. vivax malaria patients with PvCR and chloroquine sensitive parasites before treatment to identify potential molecular markers of chloroquine resistance.MethodsAn untargeted high-resolution metabolomics analysis was performed on plasma samples collected in a malaria clinic in Manaus, Brazil. Male and female patients with Plasmodium vivax were included (n = 46); samples were collected before CQ treatment and followed for 28 days to determine PvCR, defined as the recurrence of parasitemia with detectable plasma concentrations of CQ ≥100 ng/dL. Differentially expressed metabolic features between CQ-Resistant (CQ-R) and CQ-Sensitive (CQ-S) patients were identified using partial least squares discriminant analysis and linear regression after adjusting for covariates and multiple testing correction. Pathway enrichment analysis was performed using Mummichog.ResultsLinear regression and PLS-DA methods yielded 69 discriminatory features between CQ-R and CQ-S groups, with 10-fold cross-validation classification accuracy of 89.6% using a SVM classifier. Pathway enrichment analysis showed significant enrichment (p<0.05) of glycerophospholipid metabolism, glycosphingolipid metabolism, aspartate and asparagine metabolism, purine and pyrimidine metabolism, and xenobiotics metabolism. Glycerophosphocholines levels were significantly lower in the CQ-R group as compared to CQ-S patients and also to independent control samples.ConclusionsThe results show differences in lipid, amino acids, and nucleotide metabolism pathways in the plasma of CQ-R versus CQ-S patients prior to antimalarial treatment. Metabolomics phenotyping of P. vivax samples from patients with well-defined clinical CQ-resistance is promising for the development of new tools to understand the biological process and to identify potential biomarkers of PvCR.

Characterization of P. vivax blood stage transcriptomes from field isolates reveals similarities among infections and complex gene isoforms

Our understanding of the structure and regulation of Plasmodium vivax genes is limited by our inability to grow the parasites in long-term in vitro cultures. Most P. vivax studies must therefore rely on patient samples, which typically display a low proportion of parasites and asynchronous parasites. Here, we present stranded RNA-seq data generated directly from a small volume of blood from three Cambodian vivax malaria patients collected before treatment. Our analyses show surprising similarities of the parasite gene expression patterns across infections, despite extensive variations in parasite stage proportion. These similarities contrast with the unique gene expression patterns observed in sporozoites isolated from salivary glands of infected Colombian mosquitoes. Our analyses also indicate that more than 10% of P. vivax genes encode multiple, often undescribed, protein-coding sequences, potentially increasing the diversity of proteins synthesized by blood stage parasites. These data also greatly improve the annotations of P. vivax gene untranslated regions, providing an important resource for future studies of specific genes.

Quantitative Proteomics Analysis of Plasmodium vivax Induced Alterations in Human Serum during the Acute and Convalescent Phases of Infection

The radial distribution of Plasmodium vivax malaria burden has evoked enormous concern among the global research community. In this study, we have investigated the serum proteome alterations in non-severe vivax malaria patients before and during patient recuperation starting from the early febrile to the defervescence and convalescent stages of the infection. We have also performed an extensive quantitative proteomics analysis to compare the serum proteome profiles of vivax malaria patients with low (LPVM) and moderately-high (MPVM) parasitemia with healthy community controls. Interestingly, some of the serum proteins such as Serum amyloid A, Apolipoprotein A1, C-reactive protein, Titin and Haptoglobin, were found to be sequentially altered with respect to increased parasite counts. Analysis of a longitudinal cohort of malaria patients indicated reversible alterations in serum levels of some proteins such as Haptoglobin, Apolipoprotein E, Apolipoprotein A1, Carbonic anhydrase 1, and Hemoglobin subunit alpha upon treatment; however, the levels of a few other proteins did not return to the baseline even during the convalescent phase of the infection. Here we present the first comprehensive serum proteomics analysis of vivax malaria patients with different levels of parasitemia and during the acute and convalescent phases of the infection.

Investigation of lipids profile with special reference to vitamin C in vivax malaria patients in region of Sargodha

Pakistan stands among 10 countries presumed to be largest population susceptible for the vivax malaria. Vivax malaria is most often benign tertian malaria. It is often mistakenly speculated to be benign however it is actually severe and acute. Body needs vitamin C for normal physiological processes. Due to the fact vitamin C act as a strong antioxidant agent its deficiency may cause weak the body immunity. By using standard procedures and kits, the parameters estimated were as follows: vitamin C, Lipid profile (Total cholesterol, Very low-density lipoprotein (VLDL) , Low-density lipoprotein (LDL) cholesterol, High-density lipoprotein (HDL) and Total triglycerides, were evaluated by using automated analyzer, Micro Lab 300. At the end of the study it was concluded that by comparison of normal (n=43) and malarious (n=65) subjects of two age groups (≤15) and (>15) year, there were significant (p<0.05) differences observed. A significant decrease was found in vitamin C, HDL Cholesterol and LDL Cholesterol in vivax malaria patients. It was also positively correlates with severity of disease. No significant difference was observed in total cholesterol, total triglycerides and VLDL Cholesterol. The conclusion of this study was that alteration in these parameters suggests proper monitoring during treatment in order to reverse them to normal levels. Keywords: Vivax Malaria; Vitamin C; Lipid profile; Total cholesterol; HDL; VLDL http://dx.doi.org/10.19045/bspab.2017.60065

Pengaruh suplementasi seng dan vitamin B6 terhadap kadar hemoglobin, hematokrit dan indeks eritrosit pasien malaria vivax yang anemia

Background: Zinc supplementation decrease the risk of malaria parasitaemia, increasing ferritin serum level and hemoglobin in patients with malaria. Zinc influence the activity of aminolevulinic acid dehydratase (ALAD) an enzymes that catalizes heme synthesize. Vitamin B6 in pyridoxal 5-phosphate (PLP) from has a role in alpha-aminolevulinic acid (ALA) formation, which is the precursor of heme in hemoglobin. PLP also inhibit the growth of the malaria parasite.Objective: The objective was to analyze the effect of zinc and vitamin B6 supplementation on hemoglobin level, hematocrit and erythrocyte indexs (MCV, MCH and MCHC) of anemic Plasmodium vivax malaria patients.Methods: Double Blind Randomised Controlled Trial with pre and post test design. 30 subjects were divided into two groups: the suplementation group were given zinc 1x10 mg/day with vitamin B6 1x5 mg/day and the control group were given a placebo for 30 days. Data analysis by paired t-test, independent t-test and Mann Whitney.Results: There was an increase in Hb levels in the suplementation group (p=0.0001), the control group (p=0.001) and there was a significant difference on the increase between the two groups (p=0.020). Hematocrit significant increase only in the suplementation group (p=0.0001). There were no differences on erythrocyte index parameter in both groups.Conclusion: Zinc and vitamin B6 supplementation of for 30 days increase the hemoglobin level, hematocrit and there were no effect on erythrocyte indexs of anemic Plasmodium vivax malaria patients.

Characterization of Caveola-Vesicle Complexes (CVCs) Protein, PHIST/CVC-8195 in Plasmodium vivax.

Plasmodium vivax produces numerous caveola-vesicle complex (CVC) structures beneath the membrane of infected erythrocytes. Recently, a member helical interspersed subtelomeric (PHIST) superfamily protein, PcyPHIST/CVC-8195, was identified as CVCs-associated protein in Plasmodium cynomolgi and essential for survival of this parasite. Very little information has been documented to date about PHIST/CVC-8195 protein in P. vivax. In this study, the recombinant PvPHIST/CVC-8195 N and C termini were expressed, and immunoreactivity was assessed using confirmed vivax malaria patients sera by protein microarray. The subcellular localization of PvPHIST/CVC-8195 N and C termini in blood stage parasites was also determined. The antigenicity of recombinant PvPHIST/CVC-8195 N and C terminal proteins were analyzed by using serum samples from the Republic of Korea. The results showed that immunoreactivities to these proteins had 61% and 43% sensitivity and 96.9% and 93.8% specificity, respectively. The N terminal of PvPHIST/CVC-8195 which contains transmembrane domain and export motif (PEXEL; RxLxE/Q/D) produced CVCs location throughout the erythrocytic-stage parasites. However, no fluorescence was detected with antibodies against C terminal fragment of PvPHIST/CVC-8195. These results suggest that the PvPHIST/CVC-8195 is localized on the CVCs and may be immunogenic in natural infection of P. vivax.

Spleen-Dependent Immune Protection Elicited by CpG Adjuvanted Reticulocyte-Derived Exosomes from Malaria Infection Is Associated with Changes in T cell Subsets' Distribution.

Reticulocyte-derived exosomes (rex) are 30–100 nm membrane vesicles of endocytic origin released during the maturation of reticulocytes to erythrocytes upon fusion of multivesicular bodies with the plasma membrane. Combination of CpG-ODN with rex obtained from BALB/c mice infected with the reticulocyte-prone non-lethal P. yoelii 17X malaria strain (rexPy), had been shown to induce survival and long lasting protection. Here, we show that splenectomized mice are not protected upon rexPy+CpG inmunizations and that protection is restored upon passive transfer of splenocytes obtained from animals immunized with rexPy+CpG. Notably, rexPy immunization of mice induced changes in PD1− memory T cells with effector phenotype. Proteomics analysis of rexPy confirmed their reticulocyte origin and demonstrated the presence of parasite antigens. Our studies thus prove, for what we believe is the first time, that rex from reticulocyte-prone malarial infections are associated with splenic long-lasting memory responses. To try extrapolating these data to human infections, in vitro experiments with spleen cells of human transplantation donors were performed. Plasma-derived exosomes from vivax malaria patients (exPv) were actively uptaken by human splenocytes and stimulated spleen cells leading to changes in T cell subsets.

Change in Hematological disturbances in Malaria in Eastern India: an observational study

Objectives: We wanted to find out the change and pattern of hematological disturbances in patients suffering from malaria and whether the hematological disturbances had any correlation with morbidity in them.Materials and methods: In a retrospective, observational study, first 100 admitted malaria patients in a tertiary medical institute in Kolkata, was taken from August 2009 to July 2011 and their demographic, clinical and laboratorial records were noted and analysed.Results: Seventy-one patients (71%) had anemia, ninety patients (90%) had thrombocytopenia, twenty-six patients (26%) had leucopenia and two patients (2%) had leukocytosis. Vivax malaria patients had lower platelet count than their falciparum counterparts, whereas falciparum malaria patients had lower hemoglobin, packed cell volume and higher total leukocyte count; all these hematological disturbances were found to be correlated with higher morbidity in patients suffering from malaria.Conclusion: In patients suffering from malaria, there was high incidence of hematological disturbances which was changing pattern and also correlated with morbidity.Bangladesh Journal of Medical Science Vol.15(3) 2016 p.403-408

Production of Plasmodium vivax enolase in Escherichia coli and its protective properties

ABSTRACTPlasmodium vivax predominates in South-East Asia and the American continent, causes significant morbidity and inflicts a huge socioeconomic burden. Sequencing completion of the Plasmodium vivax genome and transcriptome provides the chance to identify antigens. Enolase is the eighth enzyme in the glycolytic pathway, which, apart from its glycolytic function, also possess antigenic properties and is present on the cell wall of many invasive organisms, such as Candida albicans. In order to assess whether enolase of Plasmodium vivax is also antigenic, in this study, we first reported the expression and purification of recombinant Plasmodium vivax enolase (r-Pven) in Escherichia coli, using prokaryotic expression vector. The r-Pven was expressed in soluble form in E. coli, and the expression was verified by SDS-PAGE and western blotting analysis. The r-Pven was purified to 90% purity by nickel–nitrilotriacetic acid (Ni2+–NTA) resin chromatography. For reactivity with r-Pven, compared with the average values of the reactivity of control serum samples, the average values of the reactivity of 99 individual serums from vivax malaria patients appeared higher, and there was significant difference between them (p=0.0117<0.05). Mice anti-r-Pven antibodies inhibited the growth of in vitro cultures of P. falciparum. Mice immunized with r-Pven showed protection against a challenge with the mouse malarial parasite Plasmodium berghei. The antibodies raised against r-Pven were specific for Plasmodium and did not react to the host tissues. These observations established Plasmodium vivax enolase to be a potential protective antigen.

Distribution of Antibodies Specific to the 19-kDa and 33-kDa Fragments of Plasmodium vivax Merozoite Surface Protein 1 in Two Pathogenic Strains Infecting Korean Vivax Malaria Patients

ObjectivesPlasmodium vivax merozoite surface protein 1 (PvMSP1) is the most intensively studied malaria vaccine candidate. Although high antibody response-inducing two C-terminal fragments of PvMSP1 (PvMSP1-19 and PvMSP1-42) are currently being developed as candidate malaria vaccine antigens, their high genetic diversity in various isolates is a major hurdle. The sequence polymorphism of PvMSP1 has been investigated; however, the humoral immune responses induced by different portions of this protein have not been evaluated in Korea. MethodsTwo fragments of PvMSP1 were selected for this study: (1) PvMSP1-19, which is genetically conserved; and (2) PvMSP1-33, which corresponds to a variable portion. For the latter, two representative strains, Sal 1 and Belem, were included. Thus, three recombinant proteins, PvMSP1-19, PvMSP1-33 Sal 1, and PvMSP1-33 Belem, were produced in Escherichia coli and then tested by enzyme-linked immunosorbent assays using sera from 221 patients with vivax malaria. ResultsOf the 221 samples, 198, 142, and 106 samples were seropositive for PvMSP1-19, PvMSP1-33 Sal 1, and PvMSP1-33 Belem, respectively. Although 100 samples were simultaneously seropositive for antibodies specific to all the recombinant proteins, 39 and six samples were respectively seropositive for antibodies specific to MSP1-33 Sal 1 and MSP1-33 Belem. Antibodies specific to PvMSP1-19 were the most prevalent. ConclusionMonitoring seroprevalence is essential for the selection of promising vaccine candidates as most of the antigenic proteins in P. vivax are highly polymorphic.

Therapeutic Assessment of Chloroquine-Primaquine Combined Regimen in Adult Cohort of Plasmodium vivax Malaria from Primary Care Centres in Southwestern India.

BackgroundSeveral reports of chloroquine treatment failure and resistance in Plasmodium vivax malaria from Southeast Asian countries have been published. Present study was undertaken to assess the efficacy of chloroquine-primaquine (CQ-PQ) combined regimen for the treatment of P. vivax malaria patients who were catered by the selected primary health centres (PHCs) of Udupi taluk, Udupi district, Karnataka, India.MethodFive PHCs were selected within Udupi taluk based on probability proportional to size. In-vivo therapeutic efficacy assessment of CQ (1500 mg over three days) plus PQ (210 mg over 14 days) regimen was carried out in accordance with the World Health Organization’s protocol of 28 days follow-up among microscopically diagnosed monoinfection P. vivax cohort.ResultsIn total, 161 participants were recruited in the study of which, 155 (96.3%) participants completed till day 28 follow-up, fully complied with the treatment regimen and showed adequate clinical and parasitological response. Loss to follow up was noted with 5 (3.1%) participants and non-compliance with treatment regimen occurred with one participant (0.6%). Glucose-6-phosphate dehydrogenase deficiency (G6PDd, <30% of normal mean activity) was noted among 5 (3.1%) participants and one of them did develop PQ induced dark-brown urination which subsided after PQ discontinuation. G6PDd patients were treated with PQ 45 mg/week for eight weeks while PQ was discontinued in one case with G6PD 1.4 U/g Hb due to complaint of reddish-brown coloured urine by 48 hours of PQ initiation. Nested polymerase chain reaction test revealed 45 (28%) cases as mixed (vivax and falciparum) malaria.ConclusionsThe CQ-PQ combined regimen remains outstandingly effective to treat uncomplicated P. vivax malaria in Udupi taluk and thus it should continue as first line regimen. For all P. vivax cases, G6PD screening before PQ administration must be mandatory and made available in all PHCs.