Thrombocytopenia and Plasmodium falciparum malaria in children with different exposures

Thrombocytopenia and Epistaxis Complicating Plasmodium falciparum Malaria: Case Report Study

Malaria is one of the vector-borne diseases with major public health problems to date, especially in endemic areas. Malaria is usually associated with various degrees of reduced red blood counts, and thrombocytopenia is a common association of malaria, but it is rarely associated with hemorrhagic manifestations. This case report presents two Sudanese patients, who presented to a private clinic in North Bahri. The patients were infected with Plasmodium falciparum; they developed thrombocytopenia and were presented clinically with epistaxis. A 36-year-old male and a 41-year-old male presented with the clinical features of malaria and epistaxis and were diagnosed with P. falciparum malaria. Both patients had significant thrombocytopenia in complete blood count (CBC). They showed clinical and laboratory improvement of thrombocytopenia after successful treatment of malaria. Although bleeding is a rare complication of malaria associated with thrombocytopenia, it should be considered even if it presents as a minor bleeding such as epistaxis or bleeding from gum.

Disease-specific plasma protein profiles in patients with fever after traveling to tropical areas

Fever is common among individuals seeking healthcare after traveling to tropical regions. Despite the association with potentially severe disease, the etiology is often not determined. Plasma protein patterns can be informative to understand the host response to infection and can potentially indicate the pathogen causing the disease. In this study, we measured 49 proteins in the plasma of 124 patients with fever after travel to tropical or subtropical regions. The patients had confirmed diagnoses of either malaria, dengue fever, influenza, bacterial respiratory tract infection, or bacterial gastroenteritis, representing the most common etiologies. We used multivariate and machine learning methods to identify combinations of proteins that contributed to distinguishing infected patients from healthy controls, and each other. Malaria displayed the most unique protein signature, indicating a strong immunoregulatory response with high levels of IL10, sTNFRI and II, and sCD25 but low levels of sCD40L. In contrast, bacterial gastroenteritis had high levels of sCD40L, APRIL, and IFN-γ, while dengue was the only infection with elevated IFN-α2. These results suggest that characterization of the inflammatory profile of individuals with fever can help to identify disease-specific host responses, which in turn can be used to guide future research on diagnostic strategies and therapeutic interventions.

Elevated Levels of Procoagulant Microvesicles and Tissue-Factor Bearing Microvesicles in Malaria Patients

Background

Procoagulant microvesicles (MVs) are submicron membrane fragments released from activated cells and cells undergoing apoptosis. The procoagulant activity of MVs is enhanced in the presence of tissue factor (TF). MVs and TF are active mediators that induce pro-inflammatory response and prothrombotic tendency and have been linked to the severity of several disorders, including malaria infection. The current study aimed to measure the levels of circulating procoagulant MVs and TF-bearing MVs in malaria patients and correlate these levels with other hematological parameters and parasitemia.

Materials and Methods

Levels of MVs and TF-bearing MVs in the plasma of children and adult patients infected with Plasmodium falciparum were measured alongside matched healthy controls.

Results

Patients with Plasmodium falciparum infection had ~3.8 times MVs (p < 0.0001) and ~13.0 times TF-bearing MVs compared to the matched healthy controls. MVs showed inverse significant correlation with platelet count (p = 0.0055), hemoglobin (p = 0.0004) and parasitemia.

Conclusion

Elevated levels of MVs and TF-bearing MVs could be useful biomarkers to evaluate the procoagulant activity, inflammatory response and parasitemia levels in malaria infection, aiding in better management of the disease.

Platelet Parameters and Their Correlation with Parasitemia Levels Among Malaria Infected Adult Patients at Jinella Health Center, Harar, Eastern Ethiopia: Comparative Cross-Sectional Study

Background

Malaria is a major public health problem with the highest morbidity and mortality in developing countries. Hematological changes play a great role in malaria pathogenesis through platelets and platelet parameters. However, the changes in platelet parameters are not clearly described in Ethiopia. Therefore, this study aimed to compare platelet parameters and their correlation with parasitemia among malaria-infected adult patients and healthy adults.

Methods

An institutional-based comparative cross-sectional study was conducted involving 186 (93 malaria-infected patients and 93 healthy adults) study participants using a convenient sampling technique at Jinella health center, Harar, Eastern Ethiopia, from July 10-August 10, 2022. Five milliliters of venous blood were collected from each study participant, and platelet parameters were analyzed using a Unicel (DxH 800) automated hematologic analyzer. A drop of blood was taken from malaria-suspected patients for blood film preparation. Results between two groups were compared using the Mann-Whitney U-test. Spearman's rank correlation coefficient was used to evaluate the relationships between two continuous variables. A P-value of < 0.05 was considered statistically significant.

Results

Platelet, plateletcrit, and mean platelet volume of malaria-infected patients were significantly lower as compared with healthy adults (103 x103cells/μL vs 268 x103cells/μL, 0.13 fl vs 0.23 fl, and 9.6 fl vs 15.3 fl), respectively). Conversely, platelet distribution width and platelet large cell ratio were higher in malaria-infected patients than healthy adults (19.2% vs 15.3% and 0.35% vs 0.29%), respectively). Parasitemia levels had a moderately inverse correlation with platelet count (r= -0.419) and a weakly positive correlation with mean platelet volume (r=0.278).

Conclusion

The platelet, plateletcrit, and mean platelet volume of malaria-infected patients were significantly lower as compared with healthy adults. Malaria parasitemia had a moderate inverse correlation with platelet count and a weak positive correlation with mean platelet volume. Thrombocytopenia and alteration of platelet parameters should be considered in malaria patients.

Evaluation of Antimalarial Activity of Ethanolic Extract of Annona muricata L.: An in vivo and an in silico Approach

In Nigeria, Annona muricata L. has been used to treat a variety of ailments. The mechanism of the antimalarial activity of ethanolic leaf extract of Annona muricata (EEAML) was investigated using both an in vivo and an in silico approach. The experimental mice were divided into five groups: A-F. The mice in groups B-F were inoculated with Plasmodium berghei NK-65 and treated accordingly. Groups A and B are the negative and positive controls (infected and untreated), respectively. Group C received 10 mg/kg chloroquine (standard drug), whereas groups D-F received 100, 200, and 300 mg/kg body weight of the extract orally respectively. The mice were euthanized eight days after infection, and their liver and blood were collected and used in biochemical tests. Molecular docking was performed using the extract's HPLC compounds and Plasmodium falciparum proteins. In the suppressive, prophylactic, and curative tests, there was a significant decrease (p < 0.05) in parasitemia levels in groups treated with the extract compared to the positive control and standard drug. When compared to the positive control, there was a significant (p < 0.05) reduction in liver MDA, total cholesterol, and total triglyceride levels. The binding energies of luteolin and apigenin-pfprotein complexes were significantly (p < 0.05) higher compared to their respective references. The anti-plasmodial activity of the extract may result from its hypolipidemic effect, which deprives the parasite of essential lipid molecules needed for parasite growth, as well as from the inhibitory effects of apigenin and luteolin on specific proteins required for the Plasmodium metabolic pathway.

Hematological indices and abnormalities among patients with uncomplicated falciparum malaria in Kosti city of the White Nile state, Sudan: a comparative study

BACKGROUND

Hematological abnormalities are common features in falciparum malaria but vary among different populations across countries. Therefore, we compared hematological indices and abnormalities between Plasmodium falciparum-infected patients and malaria-negative subjects in Kosti city of the White Nile State, Sudan.

METHODS

A comparative, cross-sectional study was conducted at the Clinical Laboratory Unit of Kosti Teaching Hospital from June to December 2018. A total of 392 participants (192 P. falciparum-infected patients and 200 malaria-negative subjects) were recruited in the study. Hematological indices of hemoglobin (Hb), red blood cells (RBCs), white blood cells (WBCs) and platelets were measured, and their median values were statistically compared.

RESULTS

The majority of P. falciparum-infected patients (67.6%) showed a low-level parasitemia. The median values of Hb concentration, RBC count, mean corpuscular volume (MCV), mean corpuscular Hb (MCH) and mean corpuscular Hb concentration (MCHC) were significantly lower in P. falciparum-infected patients, while the median red cell distribution width (RDW) was significantly higher in the patients compared to malaria-negative subjects. Anemia, low MCV, low MCH, low MCHC and high RDW were significantly associated with falciparum malaria, but parasitemia level was not significantly associated with anemia severity. The median total WBC count was non-significantly higher in P. falciparum-infected patients, with neutropenia being significantly associated with falciparum malaria. The median platelet count was significantly lower in P. falciparum-infected patients, with thrombocytopenia being significantly associated with falciparum malaria.

CONCLUSIONS

Falciparum malaria among patients in Kosti city of the White Nile State, Sudan is predominantly of low-level parasitemia. It is significantly associated with anemia, low MCV, low MCH, low MCHC, high RDW, thrombocytopenia and neutropenia. However, parasitemia level is not a significant predictor of anemia severity. On the other hand, leucopenia is not useful to predict falciparum malaria. Further large-scale studies in community and healthcare settings and inclusion of patients with complicated or severe malaria and those with high parasite densities are recommended.

Haematological profile of children with malaria in Sorong, West Papua, Indonesia

Background

Malaria remains a major public health problem in Indonesian Papua, with children under five years of age being the most affected group. Haematological changes, such as cytopenia that occur during malaria infection have been suggested as potential predictors and can aid in the diagnosis of malaria. This study aimed to assess the haematological alterations associated with malaria infection in children presenting with signs and symptoms of malaria.

Methods

A retrospective study was performed by collecting data from the medical records of malaria patients at Sorong Regional General Hospital, Sorong, West Papua, Indonesia, both from outpatient and inpatient clinics, from January 2014 until December 2017. The laboratory profile of children suffering from malaria was evaluated.

Results

One hundred and eighty-two children aged 1 month to 18 years old were enrolled. The subjects were mostly male (112, 61.5%) with a mean age of 6.45 years (SD = 4.3 years). Children below 5 years of age suffered the most from malaria in this study (77, 42.3%). One hundred two subjects (56%) were infected with Plasmodium falciparum. Half of the enrolled subjects (50%) had haemoglobin level (Hb) between 5.1 and 10 gr/dL. A total of 41 children (53.2%) less than 5 years old suffered from P. falciparum infection. In the age group of 5–10 years, there were 34 children (57.6%) who suffered from P. falciparum, and in the age group > 10 years, 27 children (58.7%) suffered from P. falciparum infection. Only 4 subjects (5.2%) in the less than 5 years old age group had mixed malaria infection. Among eight predictors of the haematological profile, there were five predictors that were significantly associated with the diagnostic criteria, namely haemoglobin, haematocrit, leukocytes, platelets and monocytes (p < 0.05). Generally, clinical symptoms are not significantly associated with a malaria diagnosis, and only one variable showed a significant relationship, pale, with a P value of 0.001.

Conclusions

Children with malaria had changes in some haematological markers, with anaemia, low platelet count, white blood count, and lymphocyte count being the most important predictors of malaria infection in the study area. These markers could be used to raise suspicion of malaria in children living in high endemic areas, such as West Papua.

Thrombocytopenia in malaria patients from an arid region of Western Rajasthan (India)

Context

The arid climate of Western Rajasthan is challenging for malaria transmission, with the number of cases correlating directly with the annual rainfall pattern. Moreover, >90% of the cases in this region are caused by Plasmodium vivax, which has recently been shown to cause a similar degree of thrombocytopenia as Plasmodium falciparum.

Aims and Objectives

The aim of the study was to determine the degree of thrombocytopenia in malaria patients and its association with different species of malaria in this region with an unstable malaria epidemiology.

Materials and Methods

This retrospective study was conducted on all microbiologically confirmed malaria patients with documented platelet counts from August 2017 to October 2018. Microbiological diagnosis was established by rapid diagnostic tests and peripheral blood film examination. Platelet counts were used to assess the degree of thrombocytopenia.

Results

A total of 130 cases were included in the study, of which 118 (91%) were caused by P. vivax, while the rest 12 (9%) were caused by P. falciparum. Thrombocytopenia was present in 108 (83%) cases, and the mean values of platelets in thrombocytopenic patients with P. vivax and P. falciparum infection were 72600/μL and 48500/μL, respectively. Although P. falciparum infection was significantly associated with severe thrombocytopenia (odds ratio: 4.7, [95% confidence interval 1.3-16.1]), extremely low platelet counts (n = 5) warranting platelet transfusions (n = 1) were seen only in P. vivax cases. Only one patient required platelet transfusions in these patients suggesting good tolerance to thrombocytopenia.

Conclusions

Avoiding unnecessary transfusions in febrile thrombocytopenic patients with an established malaria diagnosis can help in reducing transfusion-transmitted infections.

Uncomplicated falciparum malaria among schoolchildren in Bajil district of Hodeidah governorate, west of Yemen: association with anaemia and underweight

BACKGROUND

Malaria, malnutrition and anaemia are major public health problems in Yemen, with Hodeidah being the most malaria-afflicted governorate. To address the lack of relevant studies, this study was conducted to determine the prevalence of Plasmodium falciparum and its relation to nutritional status and haematological indices among schoolchildren in Bajil district of Hodeidah governorate, west of Yemen.

METHODS

A cross-sectional study was conducted among 400 schoolchildren selected randomly from four schools in Bajil district. Data about demographic characteristics, risk factors and anthropometric measurements of age, height and weight were collected. Duplicate thick and thin blood films were prepared, stained with Giemsa and examined microscopically for malaria parasites. The density of P. falciparum asexual stages was estimated on thick films. EDTA-blood samples were examined for the haematological indices of haemoglobin (Hb) and blood cell counts.

RESULTS

Plasmodium falciparum was prevalent among 8.0% (32/400) of schoolchildren with a mean parasite density of 244.3 ± 299.3/µL of blood and most infections showing low-level parasitaemia, whereas Plasmodium vivax was detected in one child (0.25%). Residing near water collections was a significant independent predictor of falciparum malaria [adjusted odds ratio (AOR) = 2.6, 95.0% CI 1.20-5.72; p = 0.016] in schoolchildren. Mild anaemia was prevalent among more than half of P. falciparum-infected schoolchildren and significantly associated with falciparum malaria (AOR = 5.8, 95.0% CI 2.39-14.17; p < 0.001), with a mean Hb concentration of 10.7 ± 1.0 g/dL. Although the mean values of the total white blood cells, monocytes and platelets were significantly lower in infected than non-infected schoolchildren, they were within normal ranges. More than half of the children were malnourished, with stunting (39.3%) and underweight (36.0%) being the most prevalent forms of malnutrition; 6.3% of children were wasted. Underweight (AOR = 5.3, 95.0% CI 2.09-13.62; p < 0.001) but not stunting or wasting, was a significant predictor of falciparum malaria among schoolchildren.

CONCLUSION

Asymptomatic falciparum malaria is prevalent among schoolchildren in Bajil district of Hodeidah Governorate, with predominance of low parasitaemic infections and significant association with mild anaemia and underweight. Residence near water collection is a significant predictor of infection with falciparum malaria among schoolchildren. Further studies among children with severe malaria and those with high parasite densities are recommended.

Impact of malaria on haematological parameters of urban, peri-urban and rural residents in the Ashanti region of Ghana: a cross-sectional study

Background: We aimed at investigating the impact of malaria on the haematological parameters of residents from different demographic settlements in the Ashanti Region of Ghana. Malaria parasites trigger changes in certain haematological parameters, which may result in a number of clinical manifestations. Differences in demographic settlements, such as rural, peri-urban and urban settlements may also influence these changes, but this has not been extensively studied in Ghana. Methods: We conducted a hospital-based, cross-sectional study from January to December 2018 in three different settlements. A total of 598 participants were recruited. Blood smears were examined to detect and quantify malaria parasitaemia, while haematological parameters were measured using a haematology analyser. Results: Participants from the rural settlement had the highest malaria prevalence (21.3%) compared to urban (11.8%) and peri-urban areas (13.3%); however, the peri-urban area had the highest median parasite density (568; IQR=190.0-1312.0). Age was significantly associated with the odds of malaria positivity (OR: 0.97; CI:0.96 - 0.99;  p=4.96*10 -4). When haematological parameters of the malaria-infected study participants were compared to the parameters of uninfected participants, red blood cell count (p=0.017), haemoglobin (p=0.0165), haematocrit (p=0.0015), mean corpuscular volume (p=0.0014), plateletcrit (p<0.0001) and platelet count (p<0.0001) were all significantly lower in the malaria infected group. In addition to age, haemoglobin and plateletcrit levels were also inversely correlated with the odds of testing positive for malaria, suggesting that children who were anaemic and/or thrombocytopaenic were likely to be infected. After fitting the data to a logistic regression model comprising the three variables, the model correctly categorised 78% of uninfected study participants, but only 50% of the malaria-positive participants. Conclusions: Study participants who were positive for malaria were younger and had low haemoglobin and plateletcrit levels compared to uninfected individuals. Further studies are needed to more precisely elucidate the relationship between malaria infection,demographic and haematological parameters.

Impact of malaria on haematological parameters of urban, peri-urban and rural residents in the Ashanti region of Ghana: a cross-sectional study

Background: We aimed at investigating the impact of malaria on the haematological parameters of residents from different demographic settlements in the Ashanti Region of Ghana. Malaria parasites trigger changes in certain haematological parameters, which may result in a number of clinical manifestations. Differences in demographic settlements, such as rural, peri-urban and urban settlements may also influence these changes, but this has not been extensively studied in Ghana. Methods: We conducted a hospital-based, cross-sectional study from January to December 2018 in three different settlements. A total of 598 participants were recruited. Blood smears were examined to detect and quantify malaria parasitaemia, while haematological parameters were measured using a haematology analyser. Results: Participants from the rural settlement had the highest malaria prevalence (21.3%) compared to the urban (11.8%) and peri-urban areas (13.3%); however, the peri-urban area had the highest median parasite density (568; IQR=190.0-1312.0). Age was significantly associated with the odds of malaria positivity (OR: 0.97; CI:0.96 - 0.99). When haematological parameters of the malaria-infected study participants were compared to the parameters of uninfected participants, red blood cell count (p=0.017), haemoglobin (p=0.0165), haematocrit (p=0.0015), mean corpuscular volume (p=0.0014), plateletcrit (p<0.0001) and platelet count (p<0.0001) were all significantly lower in the malaria infected group. In addition to age, haemoglobin and plateletcrit levels were also inversely correlated with the odds of testing positive for malaria, suggesting that children who were anaemic and/or thrombocytopaenic were likely to be infected. After fitting the data to a logistic regression model comprising the three variables, the model correctly categorised 78% of uninfected study participants, but only 50% of the malaria-positive participants. Conclusions: Study participants who were positive for malaria were younger and had low haemoglobin and plateletcrit levels compared to uninfected individuals. Further studies are needed to more precisely elucidate the relationship between malaria infection,demographic and haematological parameters.

Impact of malaria on haematological parameters of urban, peri-urban and rural patients in the Ashanti region of Ghana: a cross-sectional study

Background: This study aimed at investigating haematological changes in malaria patients across different demographic settlements. Malaria parasites trigger changes in certain haematological parameters, which may result in a number of clinical manifestations. Differences in demographic settlements, such as rural, peri-urban and urban settlements, may also influence these changes, but this has rarely been studied. Methods: We conducted a hospital-based, cross-sectional study from January to December 2018 in three different settlements. A total of 598 participants were recruited. Giemsa-stained blood smears were examined to detect and quantify malaria parasitaemia, while haematological parameters were measured using a haematology analyser. Results: The rural settlement had the highest malaria prevalence compared to the other study communities (p=0.009). The difference in parasite densities across the three communities was also significant (p=0.0149). When the malaria-infected population was compared to the uninfected, there were differences in red blood cell count (p=0.0170), haemoglobin levels (p=0.0165), mean corpuscular volume (p=0.0139) and platelet counts (p<0.0001). The difference in median white blood cell (p-value <0.0001), neutrophil (p-value <0.0001) and lymphocyte (p-value <0.0269) count were significantly higher in infected patients from the peri-urban area compared to malaria patients from the rural and urban areas. There were also significant differences in platelet ( p=0.0002), plateletcrit ( p=0.0041), mean platelet volume ( p=0.0009) and platelet large cell ratio ( p=0.0046) levels between patients from the urban, peri-urban and rural areas. Conclusions: Patients infected with malaria generally had low red blood cell, haemoglobin and platelets in comparison to uninfected patients. There were also significant differences in several haematological parameters between malaria-infected patients from the three demographic settlements. Atypical results from routine haematological assays, especially findings of anaemia and thrombocytopenia, may be indicative of malaria and, in cases where the infection is asymptomatic, may improve diagnosis by prompting a more thorough search for the parasite in the peripheral circulation.

Effects of malaria parasitaemia on some haemostatic parameters among pregnant women of African descent in Specialist Hospital Sokoto, Nigeria

BACKGROUND

Malaria in pregnancy is a major contributor to adverse maternal and prenatal outcome. In hyper endemic areas like ours, it is a common cause of anaemia in pregnancy and is aggravated by poor socioeconomic circumstance. This study evaluated the prothrombin time and activated partial thromboplastin time of malaria parasitized pregnant women.

METHOD

A total of 90 pregnant women participated in the study, 60 of which were malaria positive and 30 of which were malaria negative. Participants were recruited from the antenatal Clinic of Specialist Hospital Sokoto, Nigeria. A structured interviewer-administered questionnaire was used to obtain some socio-demographic characteristics of subjects. Blood samples were collected in ethylene diamine tetra acetic acid and examined for malaria parasite and platelet count while citrated samples were used for the determination of some haemostatic parameters (prothrombin time and activated partial thromboplastin time). Data generated was analyzed using SPSS 25.0 statistical package. A p-value ⩽ 0.05 was considered significant in all statistical comparisons.

RESULT

There was a statistically significant decrease (p= 0.000) in the platelet counts of the parasitized subjects compared to the non-parasitized controls. We observed a significant prolongation on both the prothrombin time and activated partial thromboplastin time among the parasitized subjects compared to the non-parasitized controls (p= 0.000).

CONCLUSION

This study has shown that malaria in pregnancy causes a significant decrease in the platelet count and prolongation in the prothrombin (PT) and the activated partial thromboplastin time (APTT). There is need for the malaria and haemostatic parameters to be assayed routinely on pregnant women particularly those presenting to antenatal clinic with febrile illness.

Characterization of platelet count and platelet indices and their potential role to predict severity in malaria

The association of hematological parameters especially platelet parameters with disease severity in malaria is poorly understood. We aimed to characterize the platelet parameters across Plasmodium falciparum and Plasmodium vivax malaria stratified by severity and to elucidate the potential role of platelet parameters to predict disease severity. Individuals > 18 years, of either gender with microscopically proven symptomatic malaria were prospectively enrolled between October 2014 and August 2016 in a tertiary center in Manipal, India. Severity of malaria was defined as per the WHO definition. Among 159 patients, 32 (20.1%) had severe malaria. 116 (73%) had infection with P. vivax, 37 (23%) P. falciparum and 6 mixed infection. Thrombocytopenia was seen in 32 (86.4%) of P. falciparum and 105 (90.5%) of P. vivax malaria cases. Patients with renal failure (p=0.02), shock (p=0.04) and liver dysfunction (p<0.001) had significantly lower platelet count compared to those who did not. Admission platelet count of 50,000 cell/mm³ had a sensitivity and specificity of 65.6% and 70.6% respectively, to discriminate severe malaria. A plateletcrit of 0.05% had a sensitivity and specificity of 65.6 % and of 70.6% respectively. Thrombocytopenia was seen in 89.3% of malaria cases due to both P. vivax and P. falciparum. Platelet count and plateletcrit could be used as markers of disease severity. P. vivax malaria which has been traditionally regarded as 'benign' can be as sinister and menacing as P. falciparum malaria and hence warrants equal attention. Unnecessary transfusion of platelets should be avoided.

Effect of Plasmodium falciparum infection on blood parameters and their association with clinical severity in adults of Odisha, India

The extent of abnormalities in blood indices and their subsequent effects on clinical severity in malaria differ among populations of different endemicity. However, these alterations have not been well investigated in Odisha, India and their prognostic implications in the context of multi-organ dysfunction (MODS) in severe malaria (SM) are not identified so far. The present study was carried out in 200 adult patients each from uncomplicated malaria and severe malaria groups to examine whether host haematological and biochemical parameters in Plasmodium falciparum infection can act as diagnostic marker for SM in adults patients of Odisha. The results showed thrombocytopenia as a potential risk factor for SM irrespective of disease features with least median platelet counts observed in patients with MODS (Platelet count: 144.5, P = < 0.0001) compared to mild malaria. Logistic regression analysis identified anemia (<10 mg/dl) as independent predictor of MODS (OR = 12.78, 95% CI = 4.93-33.2). The prognostic utility of thrombocytopenia (platelet count: ≤100,000/μl) as marker of MODS was largely modulated by hemoglobin and blood glucose level. Co-existence of hypoglycemia and thrombocytopenia was also observed. Our study revealed changes in blood indices such as low platelet, hemoglobin and blood glucose during falciparum infection in adults can be used as diagnostic criteria for predicting SM in combinations. The study also provides important clue for plausible hypoglycemia mediated platelet necrosis and clearance. Further studies in different endemic regions need to be conducted for validation of these findings and their implication as criteria for diagnosing SM in adults.

Hematological Parameters and Hemozoin-Containing Leukocytes and Their Association with Disease Severity among Malaria Infected Children: A Cross-Sectional Study at Pawe General Hospital, Northwest Ethiopia

Hematological parameter changes are the most common complications in malaria. We aimed to determine the hematological parameters and hemozoin-containing leukocytes and their association with disease severity in malaria infected children aged between 1 and 15 years. A facility-based cross-sectional study was conducted at Pawe General Hospital from July 31 to December 30, 2014. Demographic and clinical data were collected using structured questionnaire. Blood specimen was collected from each study participant for hematological investigations. Data were analyzed using SPSS version 20. The overall prevalence of anemia was 40.3%, most of which were mildly anemic. Leukocytosis was found in 15.4% of study participants. More than a fourth (27%) of the children had severe malaria. Hemozoin-containing monocytes and neutrophils were found in 80.1% and 58.9% of the study participants, respectively. Under-five years of age (AOR = 3.01, 95% CI: 1.83–7.39, P < 0.001), leukocytosis (AOR = 3.20, 95% CI: 1.65–6.24, P = 0.001), mean hemozoin-containing monocytes >5% (AOR = 6.26, 95% CI: 2.14–14.29, P < 0.001), mean hemozoin-containing neutrophils >5% (AOR = 7.93, 95% CI: 3.09–16.86, P < 0.001), and high density parasitemia (AOR = 1.90, 95% CI: 1.13–3.18, P = 0.015) were associated with severe malaria. Hemozoin-containing leukocytes, leukocytosis, and other identified associated factors should be considered for proper management of children with severe malaria.

Platelet profile is associated with clinical complications in patients with vivax and falciparum malaria in Colombia

INTRODUCTION

Thrombocytopenia is a common complication in malaria patients. The relationship between abnormal platelet profile and clinical status in malaria patients is unclear. In low and unstable endemic regions where vivax malaria predominates, the hematologic profiles of malaria patients and their clinical utility are poorly understood. The aim of this study was to characterize the thrombograms of malaria patients from Colombia, where Plasmodium vivax infection is common, and to explore the relationship between thrombograms and clinical status.

METHODS

Eight hundred sixty-two malaria patients were enrolled, including 533 (61.8%) patients infected with Plasmodium falciparum, 311 (36.1%) patients infected with Plasmodium vivax and 18 (2.1%) patients with mixed infections.

RESULTS

The most frequently observed changes were low platelet count (PC) and high platelet distribution width (PDW), which were observed in 65% of patients; thrombocytopenia with <50,000 platelets/µL was identified in 11% of patients. Patients with complications had lower PC and plateletcrit (PT) and higher PDW values. A higher risk of thrombocytopenia was identified in patients with severe anemia, neurologic complications, pulmonary complications, liver dysfunction, renal impairment and severe hypoglycemia. The presence of thrombocytopenia (<150,000 platelets/µL) was associated with a higher probability of liver dysfunction.

CONCLUSIONS

Young age, longer duration of illness and higher parasitemia are associated with severe thrombocytopenia. Our study showed that thrombocytopenia is related to malaria complications, especially liver dysfunction. High PDW in patients with severe malaria may explain the mechanisms of thrombocytopenia that is common in this group of patients.

Severe malarial thrombocytopenia: a risk factor for mortality in Papua, Indonesia

Background

The significance of thrombocytopenia to the morbidity and mortality of malaria is poorly defined. We compared the platelet counts and clinical correlates of patients with and those without malaria in southern Papua, Indonesia.

Methods

Data were collated on patients presenting to a referral hospital between April 2004 and December 2012.

Results

Platelet measurements were available in 215 479 patients (23.4%), 66 421 (30.8%) of whom had clinical malaria. Patients with Plasmodium falciparum monoinfection had the lowest platelet counts and greatest risk of severe thrombocytopenia (platelet count, <50 000 platelets/µL), compared with those without malaria (adjusted odds ratio [OR], 6.03; 95% confidence interval [CI], 5.77–6.30]). The corresponding risks were 5.4 (95% CI, 5.02–5.80) for mixed infections, 3.73 (95% CI, 3.51–3.97) for Plasmodium vivax infection, and 2.16 (95% CI, 1.78–2.63) for Plasmodium malariae infection (P < .001). In total, 1.3% of patients (2701 of 215 479) died. Patients with severe malarial anemia alone (hemoglobin level, <5 g/dL) had an adjusted OR for death of 4.93 (95% CI, 3.79–6.42), those with severe malarial thrombocytopenia alone had an adjusted OR of 2.77 (95% CI, 2.20–3.48), and those with both risk factors had an adjusted OR of 13.76 (95% CI, 10.22–18.54; P < .001).

Conclusions

Severe thrombocytopenia identifies both children and adults at increased risk of death from falciparum or vivax malaria, particularly in those with concurrent severe anemia.

Effect of malarial infection on haematological parameters in population near Thailand-Myanmar border

Background

Malaria is a major mosquito-borne public health problem in Thailand with varied haematological consequences. The study sought to elucidate the haematological changes in people who suspected malaria infection and their possible predictive values of malaria infection.

Methods

Haematological parameters of 4,985 patients, including 703 malaria-infected and 4,282 non-malaria infected, who admitted at Phop Phra Hospital, Tak Province, an area of malaria endemic transmission in Thailand during 2009 were evaluated.

Results

The following parameters were significantly lower in malaria-infected patients; red blood cells (RBCs) count, haemoglobin (Hb), platelets count, white blood cells (WBCs) count, neutrophil, monocyte, lymphocyte and eosinophil counts, while mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), Mean corpuscular haemoglobin concentration (MCHC), neutrophil-lymphocyte ratio (NLR), and monocyte-lymphocyte ratio (MLR) were higher in comparison to non-malaria infected patients. Patients with platelet counts < 150,000/uL were 31.8 times (odds ratio) more likely to have a malaria infection. Thrombocytopenia was present in 84.9% of malaria-infected patients and was independent of age, gender and nationality (P value < 0.0001).

Conclusion

Patients infected with malaria exhibited important changes in most of haematological parameters with low platelet, WBCs, and lymphocyte counts being the most important predictors of malaria infection. When used in combination with other clinical and microscopy methods, these parameters could improve malaria diagnosis and treatment.

Increased detection of Plasmodium knowlesi in Sandakan division, Sabah as revealed by PlasmoNex™

BACKGROUND

Plasmodium knowlesi is a simian malaria parasite that is widespread in humans in Malaysian Borneo. However, little is known about the incidence and distribution of this parasite in the Sandakan division, Malaysian Borneo. Therefore, the aim of the present epidemiological study was to investigate the incidence and distribution of P. knowlesi as well as other Plasmodium species in this division based on a most recent developed hexaplex PCR system (PlasmoNex™).

METHODS

A total of 189 whole blood samples were collected from Telupid Health Clinic, Sabah, Malaysia, from 2008 to 2011. All patients who participated in the study were microscopically malaria positive before recruitment. Complete demographic details and haematological profiles were obtained from 85 patients (13 females and 72 males). Identification of Plasmodium species was conducted using PlasmoNex™ targeting the 18S ssu rRNA gene.

RESULTS

A total of 178 samples were positive for Plasmodium species by using PlasmoNex™. Plasmodium falciparum was identified in 68 samples (38.2%) followed by 64 cases (36.0%) of Plasmodium vivax, 42 (23.6%) cases of P. knowlesi, two (1.1%) cases of Plasmodium malariae and two (1.1%) mixed-species infections (i e, P. vivax/P. falciparum). Thirty-five PlasmoNex™ positive P. knowlesi samples were misdiagnosed as P. malariae by microscopy. Plasmodium knowlesi was detected in all four districts of Sandakan division with the highest incidence in the Kinabatangan district. Thrombocytopaenia and anaemia showed to be the most frequent malaria-associated haematological complications in this study.

CONCLUSIONS

The discovery of P. knowlesi in Sandakan division showed that prospective studies on the epidemiological risk factors and transmission dynamics of P. knowlesi in these areas are crucial in order to develop strategies for effective malaria control. The availability of advanced diagnostic tool PlasmoNex™ enhanced the accuracy and accelerated the speed in the diagnosis of malaria.

How Reliable Are Hematological Parameters in Predicting Uncomplicated Plasmodium falciparum Malaria in an Endemic Region?

BACKGROUND

Malaria remains endemic in Sub-Saharan Africa. Hematological changes that occur have been suggested as potential predictors of malaria. This study was aimed at evaluating the diagnostic relevance of hematological parameters in predicting malaria.

METHODS

A cross-sectional study involving 370 patients with signs and symptoms of malaria was conducted at Mulago Hospital, Kampala, from May, 2012 to February, 2013. Thin and thick blood films were prepared for each patient and stained with Giemsa to aid the detection of malaria parasites. Patients' hematological parameters were determined.

RESULTS

Out of the 370 patients, 61 (16.5%) had malaria. Significant differences in the hematological parameters between P. falciparum malaria parasitemic patients and nonparasitemic patients were only observed in mean (±SD) of the differential monocyte count (10.89 ± 6.23% versus 8.98 ± 5.02%, p = 0.01) and the platelet count (172.43 (± 80.41) ×10³ cells/μl versus 217.82 ± (95.96) ×10³ cells/μl p = 0.00). The mean (±SD) values of the red blood cell indices (hemoglobin count, MCV, MCH, and MCHC), the differential neutrophil and lymphocyte counts, and the mean platelet volume (MPV) did not significantly differ between the two groups.

CONCLUSION

Hematological changes are unreliable laboratory indicators of malaria in acute uncomplicated Plasmodium falciparum malaria.

Thrombocytopenia in pregnant women with Plasmodium falciparum malaria in an area of unstable malaria transmission in eastern Sudan

BACKGROUND

Blood platelet levels are being evaluated as predictive and prognostic indicators of the severity of malaria infections in humans. However, there are few studies on platelets and Plasmodium falciparum malaria during pregnancy.

METHODS

A case-control study was conducted at Gadarif Hospital in Eastern Sudan, an area characterized by unstable malaria transmission. The aim of the study was to investigate thrombocytopenia in pregnant women with P. falciparum malaria (cases) and healthy pregnant women (controls).

RESULTS

The median (interquartile) platelet counts were significantly lower in patients with malaria (N = 60) than in the controls (N = 60), 61, 000 (43,000-85,000) vs. 249,000 (204,000-300,000)/μL, respectively, p < 0.001. However, there was no significant difference in the platelet counts in patients with severe P. falciparum malaria (N = 12) compared with those patients with uncomplicated P. falciparum malaria (N = 48), 68, 000 (33,000-88,000)/μL vs. 61, 000 (45,000-85,000)/μL, respectively, p = 0.8. While none of the control group had thrombocytopenia (platelet count <75, 000/μL), it was found that 6/12 (50%) and 27/48 (56.2%) (p <0.001) of the patients with severe malaria and uncomplicated malaria had thrombocytopenia, respectively. Pregnant women with P. falciparum malaria, compared with the pregnant healthy control group, were at higher risk (OR = 10.1, 95% CI = 4.1-25.18; p < 0.001) of thrombocytopenia. Two patients experienced bleeding, and there was one maternal death due to cerebral malaria where the patient's platelet count was only 28,000/μL.

CONCLUSION

P. falciparum malaria is associated with thrombocytopenia in pregnant women in this setting. More research is needed.

[Malaria severity criteria and prognostic factors among children in Dakar]

INTRODUCTION

Severity factors associated with malaria as well as prognostic factors for death were assessed at the Dakar Centre Hospitalier National d'Enfants Albert Royer de Fann (CHNEAR).

PATIENTS AND METHODS

A prospective study was carried out from January 1 to December 31, 2007 involving children from 0 to 15 years of age, admitted for plasmodium falciparum malaria with positive thick drop examination, meeting at least one of the WHO 2000 malaria severity criteria. Acidosis was not studied.

OUTCOME

The rate of severe malaria cases in our hospital was 6.4%. The sex ratio was 1.4 and the median age of patients at 91 months. A peak was observed during the 4th trimester (75.5%). Convulsions (52.5%) and obtundation (49.4%) were the most common signs of clinical severity while hyperparasitemia and severe anemia ranged at 27.2% and 21.6%, respectively. Lethality was 11.1% and the main death risk factors were young age (p = 0.025), coma (p = 0.007), respiratory distress (p = 0.04), or hypoglycemia (p = 0.001).

CONCLUSION

Reducing malaria hospital mortality in Senegal may be obtained by proper management of poor prognostic factors such as coma, respiratory distress, and hypoglycemia.

Impact of Plasmodium falciparum infection on haematological parameters in children living in Western Kenya

Background

Malaria is the commonest cause of childhood morbidity in Western Kenya with varied heamatological consequences. The t study sought to elucidate the haemotological changes in children infected with malaria and their impact on improved diagnosis and therapy of childhood malaria.

Methods

Haematological parameters in 961 children, including 523 malaria-infected and 438 non-malaria infected, living in Kisumu West District, an area of malaria holoendemic transmission in Western Kenya were evaluated.

Results

The following parameters were significantly lower in malaria-infected children; platelets, lymphocytes, eosinophils, red blood cell count and haemoglobin (Hb), while absolute monocyte and neutrophil counts, and mean platelet volume (MPV) were higher in comparison to non-malaria infected children. Children with platelet counts of <150,000/uL were 13.8 times (odds ratio) more likely to have malaria. Thrombocytopaenia was present in 49% of malaria-infected children and was associated with high parasitaemia levels, lower age, low Hb levels, increased MPV and platelet aggregate flag. Platelet aggregates were more frequent in malaria-infected children (25% vs. 4%, p<0.0001) and associated with thrombocytopaenia rather than malaria status.

Conclusion

Children infected with Plasmodium falciparum malaria exhibited important changes in some haematological parameters with low platelet count and haemoglobin concentration being the two most important predictors of malaria infection in children in our study area. When used in combination with other clinical and microscopy, these parameters could improve malaria diagnosis in sub-patent cases.

Hyponatraemia in imported malaria is common and associated with disease severity

BACKGROUND

Hyponatraemia (serum sodium < 135 mmol/L) has long been recognized as a complication of malaria. However, few studies have been done in non-immune adult populations. It has not been investigated previously how hyponatraemia is distributed among the various Plasmodium species, and its association with malaria severity is unknown.The aim of this retrospective cohort study was to determine the prevalence of hyponatraemia and its association with malaria severity in a large cohort of patients with imported malaria caused by various Plasmodium species.

METHODS

All patients that were diagnosed with malaria in the Harbour Hospital and Institute for Tropical Diseases in Rotterdam in the period 1999-2009 and who had available serum sodium on admission were included. Severe malaria was defined according to the modified WHO criteria. Prevalence of hyponatraemia and its association with malaria severity were investigated by univariate comparison, ROC analysis and multivariate logistic regression analysis.

RESULTS

A total of 446 patients with malaria (severe falciparum malaria n = 35, non-severe falciparum malaria n = 280, non-falciparum malaria n = 131) was included. Hyponatraemia was present in 207 patients (46%). Prevalence and severity of hyponatraemia were greatest in severe falciparum malaria (77%, median serum sodium 129 mmol/L), followed by non-severe falciparum malaria (48%, median serum sodium 131 mmol/L), and non-falciparum malaria (34%, median serum sodium 132 mmol/L). Admission serum sodium < 133 mmol/L had a sensitivity of 0.69 and a specificity of 0.76 for predicting severe malaria. Multivariate logistic regression showed that serum sodium < 131 mmol/L was independently associated with severe falciparum malaria (odds ratio 10.4, 95% confidence interval 3.1-34.9). In patients with hyponatraemia, hypovolaemia did not appear to play a significant role in the development of hyponatraemia when prerenal azotaemia and haematocrit were considered as surrogate markers for hypovolaemia.

CONCLUSIONS

Hyponatraemia is common in imported malaria and is associated with severe falciparum malaria. From a clinical point of view, the predictive power of hyponatraemia for severe malaria is limited. The precise pathophysiological mechanisms of hyponatraemia in malaria require further study.

[Imported malaria: diagnostic traps and rapid tests]

Imported malaria is a disease prevalent in France: 6,000 to 8,000 cases a year, of which 15% are pediatric cases. Despite this high incidence, the diagnosis is often delayed. The patient may then evolve to a severe form. This diagnostic delay is due to non-specific clinical symptoms in children. The most common symptoms are fever and digestive disorders (diarrhea, vomiting). In the absence of thrombocytopenia, the laboratory tests are not very useful for diagnosis. Parasitological examinations are dependent on the experience of the biologist, particularly in cases of low parasitemia as those observed in children who have received partial chemoprophylaxis. The recent introduction of rapid tests based on the detection of Plasmodium proteins, allows emergency remedy to this problem. The blood smears remains the gold standard and has to be used to confirm the results of rapid tests. If rapid tests improve the detection of Plasmodium in 2009, it remains mandatory to evoke the diagnosis of malaria in any febrile child coming from an endemic area.

Clinical and laboratory features of human Plasmodium knowlesi infection

BACKGROUND

Plasmodium knowlesi is increasingly recognized as a cause of human malaria in Southeast Asia but there are no detailed prospective clinical studies of naturally acquired infections.

METHODS

In a systematic study of the presentation and course of patients with acute P. knowlesi infection, clinical and laboratory data were collected from previously untreated, nonpregnant adults admitted to the hospital with polymerase chain reaction-confirmed acute malaria at Kapit Hospital (Sarawak, Malaysia) from July 2006 through February 2008.

RESULTS

Of 152 patients recruited, 107 (70%) had P. knowlesi infection, 24 (16%) had Plasmodium falciparum infection, and 21 (14%) had Plasmodium vivax. Patients with P. knowlesi infection presented with a nonspecific febrile illness, had a baseline median parasitemia value at hospital admission of 1387 parasites/microL (interquartile range, 6-222,570 parasites/microL), and all were thrombocytopenic at hospital admission or on the following day. Most (93.5%) of the patients with P. knowlesi infection had uncomplicated malaria that responded to chloroquine and primaquine treatment. Based on World Health Organization criteria for falciparum malaria, 7 patients with P. knowlesi infection (6.5%) had severe infections at hospital admission. The most frequent complication was respiratory distress, which was present at hospital admission in 4 patients and developed after admission in an additional 3 patients. P. knowlesi parasitemia at hospital admission was an independent determinant of respiratory distress, as were serum creatinine level, serum bilirubin, and platelet count at admission (p < .002 for each). Two patients with knowlesi malaria died, representing a case fatality rate of 1.8% (95% confidence interval, 0.2%-6.6%).

CONCLUSIONS

Knowlesi malaria causes a wide spectrum of disease. Most cases are uncomplicated and respond promptly to treatment, but approximately 1 in 10 patients develop potentially fatal complications.

Changes in the total leukocyte and platelet counts in Papuan and non Papuan adults from northeast Papua infected with acute Plasmodium vivax or uncomplicated Plasmodium falciparum malaria

BACKGROUND

There are limited data on the evolution of the leukocyte and platelet counts in malaria patients.

METHODS

In a clinical trial of chloroquine vs. chloroquine plus doxycycline vs. doxycycline alone against Plasmodium vivax (n = 64) or Plasmodium falciparum (n = 98) malaria, the total white cell (WCC) and platelet (PLT) counts were measured on Days 0, 3, 7 and 28 in 57 indigenous Papuans with life long malaria exposure and 105 non Papuan immigrants from other parts of Indonesia with limited malaria exposure.

RESULTS

The mean Day 0 WCC (n = 152) was 6.492 (range 2.1-13.4) x 10(9)/L and was significantly lower in the Papuans compared to the non Papuans: 5.77 x 10(9)/L vs. 6.86 x 10(9)/L, difference = -1.09 [(95% CI -0.42 to -1.79 x 10(9)/L), P = 0.0018]. 14 (9.2%) and 9 (5.9%) patients had leukopaenia (<4.0 x 10(9)/L) and leukocytosis (>10.0 x 10(9)/L), respectively. By Day 28, the mean WCC increased significantly (P = 0.0003) from 6.37 to 7.47 x 10(9)/L (73 paired values) and was similar between the two groups. Ethnicity was the only WCC explanatory factor and only on Day 0.The mean Day 0 platelet count (n = 151) was 113.0 (range 8.0-313.0) x 10(9)/L and rose significantly to 186.308 x 10(9)/L by Day 28 (P < 0.0001). There was a corresponding fall in patient proportions with thrombocytopaenia (<150 x 10(9)/L): 119/151 (78.81%) vs. 16/73 (21.92%, P < 0.00001). Papuan and non Papuan mean platelet counts were similar at all time points. Only malaria species on Day 0 was a significant platelet count explanatory factor. The mean D0 platelet counts were significantly lower (P = 0.025) in vivax (102.022 x 10(9)/L) vs. falciparum (122.125 x 10(9)/L) patients.

CONCLUSION

Changes in leukocytes and platelets were consistent with other malaria studies. The Papuan non Papuan difference in the mean Day 0 WCC was small but might be related to the difference in malaria exposure.

Laboratory indicators of the diagnosis and course of imported malaria

When travellers return from malaria-endemic areas and present to hospital with fever, microscopy of blood smears remains the leading method to verify a suspected diagnosis of malaria. Additional laboratory abnormalities may, however, also be indicative of acute malaria infection. We monitored prospectively a group of patients with imported Plasmodium falciparum (n=28) or P. vivax/P. ovale (n=12) infection, respectively, and assessed haemoglobin, leucocytes, thrombocytes, C-reactive protein, coagulation factor II-VII-X, lactate dehydrogenase and bilirubin during 7 d of admission and weekly until d 28. For comparison, admission values of a group of febrile patients with suspected malaria, but with negative blood slides, were also assessed (n=66). The thrombocyte, leucocyte counts and coagulation factor II-VII-X were significantly lower in the malaria group compared to the non-malaria group, whereas the C-reactive protein, lactate dehydrogenase and bilirubin were significantly higher in the malaria group. The differences were particularly strong with falciparum malaria. By contrast, haemoglobin levels were not affected. In conclusion, our study emphasizes the role of a few commonly analysed laboratory parameters, in particular thrombocyte counts, in guiding the clinician managing a returning traveller with fever.

Delay in diagnosis of imported Plasmodium falciparum malaria in children

The study reported here prospectively evaluated the time-to-diagnosis of imported Plasmodium falciparum malaria in children in seven French pediatric emergency departments during a 1-week period. For the 29 patients included, the mean patient, doctor and total delays were 3.1, 1.5 and 4.7 days, respectively. The late medical diagnosis for 11 patients was mainly due to the treating physician's failure to consider malaria, despite having been informed that the child had been in an endemic area, and erroneously making a diagnosis of viral infection. The five patients who were diagnosed correctly without delay had higher mean platelet counts than the others (206,000 vs 118,541/mm(3); p=0.008). The results indicate that greater awareness of the risk of malaria in returning travelers may help reduce delays in diagnosis and its consequences.