Platelet Hypersensitivity in Acute Malaria (Plasmodium falciparum) Infection in Man

1981 ◽  
Vol 46 (02) ◽  
pp. 547-549 ◽  
Author(s):  
E M Essien ◽  
M I Ebhota
Keyword(s):  
Plasmodium Falciparum ◽  
Malaria Infection ◽  
Light Transmission ◽  
Human Platelet ◽  
Platelet Rich Plasma ◽  
Wave Pattern ◽  
Falciparum Infection ◽  
Secondary Wave ◽  
Control Subjects ◽  
The Mean

SummaryDuring acute malaria infection, platelets in human platelet-rich plasma are hypersensitive to the addition of ADP between 1.0 uM and 5.0 uM, or adrenaline 0.11 uM as aggregating agents. The mean maximum aggregation amplitude (as % of light transmission) obtained from 8 subjects in response to added ADP (1.0 uM), 39.8 ± 27 (1SD), was significantly greater than the value in 6 controls (5.2±6.7 (1SD); t = 3, 51 P <0.005). A similar pattern of response was obtained with higher ADP concentrations (2.4,4.5 or 5.0 uM) in 22 patients and 20 control subjects (89.9±14.9% vs 77.8±16.5% (1SD) t = 2.45, P <0.02). Addition of 4.5 uM ADP to patient PRP usually evoked only a single aggregation wave (fused primary and secondary waves) while the typical primary and secondary wave pattern was usually obtained from controls.Mean plasma B-thromboglobulin (BTG) concentration in 7 patients (208.3 ± 15.6 ng/ml) was significantly higher than the value in 6 control subjects (59.2±15.7 ng/ml; t = 13.44, P <0.002).

Platelet Hypersensitivity In Acute Malaria Infection (Plasmodium Falciparum) In Man

1981 ◽  
Author(s):  
E M Essien ◽  
M I Ebhota
Keyword(s):  
Plasmodium Falciparum ◽  
Platelet Aggregation ◽  
Malaria Infection ◽  
Light Transmission ◽  
Similar Response ◽  
Aggregation Response ◽  
The Mean ◽  
Age Range

We had earlier reported altered ADP-induced platelet aggregation in man during acute malaria infection. The present study sought to determine (i) whether the changes suggested platelet hypersensitivity to ADP and (ii) whether such changes occurred in vivo or in vitro.The aggregation response of platelets (as citrated PRP) to addition of ADP from thirty patients with acute malaria infection has been compared with that of 29 control i.e., non-infected subjects. The age range of the subjects in both groups varied from 2 to 70 years. These tests were performed before the patients took any drugs. With addition of l.0μM ADP to 1 ml of PRP, the mean aggregation amplitude (as % light transmission) obtained from 8 patients, 39.8±27.1% was significantly greater than that from 9 control subjects (5.2±6.7%; t = 3.51; P < 0.005). With higher ADP concentrations (2.4 - 5.0μM) similar response in 22 subjects (mean 89.1±14.9%) was also significantly greater than that in 20 controls (77.8±16.5%; t = 12.45; P < 0.02). These results suggest that during acute malaria infection in man, circulating platelets become hypersensitive to ADP in vitro. No instances of spontaneous aggregation were however observed in the patients.βTG was determined in 7 patients and 6 controls. The mean plasma βTG in the patients (208.3±15.6 ng/ml) was significantly higher than that in controls (59.2±15.7 ng/ml; t = 13.44; P <0.001). These latter results suggest that the platelets were probably activated in vivo to release the βTG. They further suggest that the hypersensitive changes noted earlier also probably occurred in vivo.It is suggested that acute malaria (P.falciparum) infection in man is probably another clinical condition associated with platelet hypersensitivity.

scholarly journals Kinetics of ADP-induced human platelet shape change: apparent positive cooperativity

1980 ◽  
Vol 58 (1) ◽  
pp. 45-52 ◽  
Author(s):  
John G. Milton ◽  
W. Yung ◽  
C. Glushak ◽  
M. M. Frojmovic
Keyword(s):  
Light Transmission ◽  
Human Platelet ◽  
Platelet Rich Plasma ◽  
Shape Change ◽  
Hill Coefficient ◽  
A Value ◽  
The Hill ◽  
Kinetics Of ◽  
Type Response ◽  
Platelet Shape

The kinetics of ADP-induced human platelet shape change have been examined. Initial velocities of platelet shape change were estimated by two methods: (1) the slope of the initial decrease in light transmission through stirred, citrated platelet-rich plasma, and (2) direct examination of platelet morphologies by phase-contrast microscopy. In both cases, a value of the Hill coefficient, NH, significantly greater than 1 is obtained (2.0 ± 0.2 and 1.8 ± 0.2, respectively). The observed elevated value of NH is not due to a substantial fraction of the ADP being platelet bound, the presence of factors in the plasma, platelet heterogeneity, or the influence of the rate of platelet shape change reversion. Our observations suggest that ADP-induced platelet shape change may be a positively cooperative or "threshold" type response.

Dipyridamole (D) Reduces the Effectiveness of Prostaglandin (PG) I2. PGD2 and PGE1 as Inhibitors of Platelet Aggregation in Human Platelet-Rich Plasma (PRP)

1979 ◽  
Author(s):  
Di G. Minno ◽  
de G. Gaetano ◽  
M.J. Silver
Keyword(s):  
Platelet Aggregation ◽  
Inhibitory Concentration ◽  
Human Platelet ◽  
Platelet Rich Plasma ◽  
Inhibitory Effect ◽  
Mechanisms Of Action ◽  
Phosphodiesterase Activity ◽  
Inhibition Of Platelet Aggregation ◽  
Normal Humans ◽  
The Mean

The effectiveness and the mechanism of action of D as an anti-thrombotic agent has been controversial. It has been proposed that D works by potentiating the inhibitory activity of "circulating" PGE2 on platelet aggregation by inhibiting platelet phosphodiesterase activity. To determine whether such potentiation exists in normal humans we studied inhibition of aggregation by the PGs in PRP before and 90 mln after the ingestion of D (100 mg). As expected, we found that the threshold aggregating concentrations of ADP, collagen and arachidonic acid (AA) were unchanged after the ingestion of D. Unexpectedly, the threshold inhibitory concentration of each PG was greater after ingestion of D than before. The mean elevations for PGI2 were 8.8 nM (p<0.05) vs ADP; 9.1 nM(p<0 01) ys collagen; 9.2 nM (p<0.001) vs AA; for FCD2 14.5 nM (p<0.05) vs AA; for PGE, 69 0 nM (p<0.05) vs collagen and 25.9 nM (p<0.05) vs AA. The elevations for PGD2 vs ADP and collagen and for PGE1 vs ADP were not significant. These data do not support the hypothesis that D aces as an anti-thrombotic agent by potentiating the inhibition of platelet aggregation by “circulating” PGIZ. The findings show that ingestion of D Interferes with the inhibitory effect of the PGs and suggest that other mechanisms of action ot D should be investigated.(Supported by the Italian CNR and NIH).

scholarly journals Plasmodium falciparum Infection Does Not Affect Human Immunodeficiency Virus Viral Load in Coinfected Rwandan Adults

2014 ◽  
Vol 1 (2) ◽  
Author(s):  
Krishanthi Subramaniam ◽  
Rebeca M. Plank ◽  
Nina Lin ◽  
Adam Goldman-Yassen ◽  
Emil Ivan ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Drug Resistance ◽  
Plasmodium Falciparum ◽  
Viral Load ◽  
Malaria Infection ◽  
Hiv Transmission ◽  
Falciparum Infection ◽  
Resistance Testing ◽  
Plasmodium Falciparum Infection ◽  
Immunodeficiency Virus

Abstract Background.  Plasmodium falciparum infection has been reported to increase human immunodeficiency virus (HIV) viral load (VL), which can facilitate HIV transmission. We prospectively studied the impact of mild P falciparum coinfection on HIV VL in Rwanda. Methods.  We measured plasma HIV VL at presentation with malaria infection and weekly for 4 weeks after artemether-lumefantrine treatment in Rwandan adults infected with HIV with P falciparum malaria. Regression analyses were used to examine associations between malaria infection and HIV VL changes. Samples with detectable virus underwent genotypic drug-resistance testing. Results.  We enrolled 28 HIV-malaria coinfected patients and observed 27 of them for 5 weeks. Three patients (11%) were newly diagnosed with HIV. Acute P falciparum infection had no significant effect on HIV VL slope over 28 days of follow-up. Ten patients with VL &lt;40 copies/mL at enrollment maintained viral suppression throughout. Seventeen patients had a detectable VL at enrollment including 9 (53%) who reported 100% adherence to ARVs; 3 of these had detectable genotypic drug resistance. Conclusions.  Unlike studies from highly malaria-endemic areas, we did not identify an effect of P falciparum infection on HIV VL; therefore, malaria is not likely to increase HIV-transmission risk in our setting. However, routine HIV testing should be offered to adults presenting with acute malaria in Rwanda. Most importantly, we identified a large percentage of patients with detectable HIV VL despite antiretroviral (ARV) therapy. Some of these patients had HIV genotypic drug resistance. Larger studies are needed to define the prevalence and factors associated with detectable HIV VL in patients prescribed ARVs in Rwanda.

scholarly journals Evidence of Plasmodium falciparum infection after 12 years from the exposure: cryptic malaria or recrudescence?

2021 ◽  
Author(s):  
Ildebrando Patamia ◽  
Elisa Cappello ◽  
Maddalena Calvo ◽  
Giuseppe Migliorisi ◽  
Antonina Franco
Keyword(s):  
Plasmodium Falciparum ◽  
Case Report ◽  
Malaria Infection ◽  
Local Population ◽  
Clinical History ◽  
Falciparum Infection ◽  
Antimalarial Treatment ◽  
Endemic Region ◽  
Plasmodium Falciparum Infection

Abstract BackgroundMalaria infections affect a high percentage of the world's population, especially in tropical and subtropical regions. Specifically, Plasmodium falciparum is the most relevant species involved in the etiopathogenesis of this infection. The duration of P. falciparum infections is often undefined, as some reported episodes of suspected recrudescence occur several years after initial exposure.Case presentationWe present a case report of malaria infection with low parasitaemia in a man whose last stay in an endemic region or contacts with the local population was twelve years ago. The patient recovered fully with adequate antimalarial treatment, but some aspects of his clinical history were not clearly defined.ConclusionsWe discuss here the possibility that this is either a P. falciparum recrudescence or an episode of cryptic malaria, as we cannot carefully verify some details of our patient's life and history.

Free Platelet Count and Size Distribution During C1q Inhibition of Collagen-Induced Platelet Aggregation

1987 ◽  
Vol 58 (02) ◽  
pp. 682-685 ◽  
Author(s):  
Gyorgy Csako ◽  
Eva A Suba
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Light Transmission ◽  
Platelet Rich Plasma ◽  
Inhibitory Effect ◽  
Lag Phase ◽  
Large Platelet ◽  
Median Volume ◽  
Platelet Aggregates ◽  
The Mean

SummaryElectronic free platelet counting was more sensitive than turbidimetry to detect collagen-induced platelet activation in human platelet-rich plasma. Purified human Clq exhibited a greater inhibitory effect on collagen-induced platelet aggregation in turbidimetry than free platelet counting. Because the change from small to large platelet aggregates is responsible for the continuing increase in light transmission, Clq was likely more capable of blocking the formation of large platelet aggregates than the formation of small aggregates from single platelets. The iattr uf change by cullagcn in light tiansmissiun and fiec platelet count was reduced in the presence of Clq but the timing of the peak response remained the same. Electronic platelet sizing revealed that the volume of single platelets transiently increased during the turbidimetric “lag phase”. The mean, mode and median volume of the remaining free platelets then decreased, suggesting a selective loss of large, functionally more active platelets and/or platelet degranulation. Clq had no effect on the volume increment during the “lag phase”, but reduced the subsequent fall in the volume of free platelets.

scholarly journals Mild Depression of Platelet Count and Altered Platelet Function in Acute Plasmodium Falciparum Infection

1977 ◽  
Author(s):  
E. M. Essien ◽  
M. I. Ebhota
Keyword(s):  
Plasmodium Falciparum ◽  
Platelet Count ◽  
Healthy Adult ◽  
Falciparum Infection ◽  
Malaria Parasitaemia ◽  
Mild Depression ◽  
Aggregation Factor ◽  
The Mean ◽  
Induced Aggregation ◽  
Second Wave

We recently examined a possible role and extent of involvement of Plasmodium falciparum para-sitaemia in our earlier report of significantly lower circulating platelet numbers in healthy adult Nigerians (100 – 300x 103/ul) compared with matched Caucasians (150 – 140 χ 103/ml) ; (P<. 0.001), and in view of recently reported association of Plasmodium parasitaemia with thrombocytopaenia, consumptive coagulopathy (DIC) and other haemorrhagic syndromes. Ninety-eight febrile children aged between 8 months and 10 years whose fever was attributed to malaria parasitaemia only were admitted into the study. Platelet count, platelet aggregation, Factor VIII and FDP were determined on each blood sample which was collected before treatment was started. Tests were repeated 10-Hdays later. It was found that the mean platelet count of 132,000+61, 620/ul (1SD) during illness and immediately after treatment was significantly lower than the count of 234, 400+98, 480/ul, 10–14 days later, (t = 6.496 ; P<c 0.001 ). Significant thrombo cy topa emia (Platelets 70,000/ul) was observed only in Gfo of the subjects and none had any haemorrhagic symptoms. The effect was independent of age or degree of parasitaemia. Pre- and post-treatment leucocyte counts were similarly different (7952+2043 vs. 9221+3071 t = −2.81; P<0.05). Haematocrit values did not change significantly. However, in the response to platelet aggregating agents, it was found that the second wave of ADP-induced aggregation was regularly abolished during the parasitaemia.It is concluded that in hyperendemic Plasmodium falciparum environment, the malaria may often lead to mild depression of platelet count but that severe thrombocytopaenia is uncommon. The platelets may not be optionally functional.

scholarly journals Epidemiological trends of malaria in the Western regions of Saudi Arabia: a cross sectional study

2020 ◽  
Vol 14 (11) ◽  
pp. 1332-1337
Author(s):  
Omar SO Amer ◽  
Mohamed I Waly ◽  
Izhar W Burhan ◽  
Esam S Al-Malki ◽  
Amor Smida ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Saudi Arabia ◽  
Malaria Infection ◽  
Plasmodium Malariae ◽  
Cross Sectional Study ◽  
Age Group ◽  
Cross Sectional ◽  
The Mean ◽  
Almost All ◽  
Epidemiological Trends

Introduction: Saudi Arabia has successfully reduced malaria cases to be constrained largely in the western regions. This study aimed to determine the epidemiological trends of malaria infection in five western regions of Saudi Arabia. Methodology: A retrospective analysis was conducted to investigate the epidemiological trends of malaria infection in the western regions, based on the published registry of the Saudi Ministry of Health, during the period from 2014 to 2017 using the appropriate statistical tools. Results: A total of 8925 confirmed cases of malaria were reported in the western regions during the period from 2014 to 2017 with the mean of 2231 malaria cases per year. The minimum (n = 1097) and maximum (n = 4075) number of cases were reported in 2014 and 2016 respectively. The highest (n = 5919, 66.3%) number of cases were reported from Jazan region, while lowest (n = 86, 1.0%) number of cases were reported from Al-Bahah region. Plasmodium falciparum was the most frequently reported species with 7485 (83.9%) cases, while Plasmodium vivax accounted 1386 (15.5%) cases. Plasmodium malariae and mixed infections were insignificant and accounted 0.5% (n = 48) and 0.1% (n = 6) cases respectively. In relation to malaria infection and age group, malaria was predominant in > 15 age group. The highest number of malaria cases in almost all years was observed from January until March and the lowest number was reported from May until July. Conclusions: Plasmodium falciparum was the most dominant species in this survey and Jazan was the most affected region.

scholarly journals Erythrocytic Antioxidant Enzymes, Plasma Malondialdehyde and Haemoglobin Levels in Plasmodium Falciparum Infected Malaria Patients in Lagos, Nigeria

2021 ◽  
pp. 1-12
Author(s):  
Ugochukwu Okechukwu Ozojiofor ◽  
Paul Gbenga Olawale ◽  
Ebipade Kereakede ◽  
Abba Umar Hassan ◽  
Kingsley Onuh ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Plasmodium Falciparum ◽  
Human Subjects ◽  
Age Groups ◽  
Oxidative Stress Biomarkers ◽  
Control Subjects ◽  
Anti Oxidant ◽  
The Mean ◽  
Plasma Malondialdehyde

This study investigated the effect of malaria parasitaemia on Plasmodium falciparum infected human erythrocytes oxidative stress biomarkers and haemoglobin levels. Seventy (70) human subjects of fifty (50) P. falciparum positive and twenty (20) control subjects between the ages of 10-60 years were selected for this study. Rapid Diagnostic Test (RDT) and microscopy were used to identify P. falciparum. The samples were matched based on age, sex and level of parasitaemia. Samples of blood were collected for the determination of P. falciparum, level of parasitaemia, anti-oxidant assay and haemoglobin levels; to assess the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), malondialdehyde (MDA), total protein (PRO), reduced glutathione (GSH), haemoglobin and Parasite density. Haemoglobin level was determined using a Coulter A-T Pierce haematology analyzer (Beckman Coulter, Inc. Fullerton, CA, USA). This study showed that the mean level of PRO, CAT, MDA and SOD was significantly higher among the P. falciparum positive patients to those in the control while GPx level was lower, also, the mean level of HGB was significantly lower in the P. falciparum positive patients to those in the control. MDA, SOD, GSH and PRO level were higher among age group (10-20) in the P. falciparum infected patients and lower in the control subjects when compared to other age groups. MDA, SOD and PRO level were higher in the males than the females in both the malaria positive and controls. This study indicates that high parasitaemic patients are at greater risk of anaemia and oxidative stress compared to low parasitaemic ones.

scholarly journals Plasmodium falciparum infection during pregnancy in an unstable transmission area in eastern Sudan

2003 ◽  
Vol 9 (4) ◽  
pp. 570-580 ◽  
Author(s):  
G. El Ghazali ◽  
I. Adam ◽  
A. Hamad ◽  
M. I. El Bashir
Keyword(s):  
Plasmodium Falciparum ◽  
Haemoglobin Concentration ◽  
Antenatal Clinic ◽  
Falciparum Infection ◽  
Plasmodium Falciparum Infection ◽  
Significant Difference ◽  
Transmission Area ◽  
Malaria During Pregnancy ◽  
The Mean ◽  
Eastern Sudan

A 1-year prospective community-based study of malaria during pregnancy was conducted in an area of seasonal and unstable malaria transmission in eastern Sudan. At a village antenatal clinic, 89 non-pregnant controls and 86 pregnant women were enrolled and followed every 2 weeks until 6 weeks after delivery. The incidence of Plasmodium falciparum infection was significantly higher among pregnant than control women [17.4% versus 5.6%] with no difference between primigravidae and multigravidae [22.2% versus 15.2%]. There was no significant difference in the mean haemoglobin concentration between infected and uninfected mothers [9.1 +/- 1.3 versus 9.5 +/- 0.6 g/dL] but the mean birth weight of their babies was significantly lower [2.72 +/- 0.26 versus 2.95 +/- 0.05 kg] despite prompt case management of infected women

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