Gender Based Variations of Haematological Parameters of Patients with Asymptomatic Malaria in Akure, Ondo State, Nigeria

The study was done to evaluate the variations of haematological parameters of patients with asymptomatic malaria based on gender. The study is a cross-sectional study among asymptomatic malaria patients and patients who are apparently healthy individuals. The subjects were selected Original Research Article Obeagu et al.; JPRI, 33(8): 75-80, 2021; Article no.JPRI.65994 76 using a well-structured questionnaire who were age and sex matched. This study was conducted on asymptomatic malaria patients and apparently healthy individuals in the Oda Road area of Akure, Ondo State. Two hundred (200) asymptomatic malaria patients, 100 subjects each for males and females were recruited for this study. 5ml of venous blood was collected from each participant into an EDTA bottle which was then used for the determination of full blood count and Malaria. The results showed increase in PCV (p=0.000), RBC (p=0.000), Hb (p=0.000) and no significant difference in WBC (p=0.180), LYM (p=0.841), GRAN (p=0.986), MID (p=0.395), MCV (p=0.111), MCH (p=0.191), MCHC (p=0.791), Plt (p=0.959) when compared between male and female respectively. The study showed increase in packed cell volume, haemoglobin and red blood cells of male compared to females of asymptomatic malaria patients. There were no variations in other haematological parameters studied. The changes in the red cell line may be associated to bone marrow activity difference in the patients and effects of hormonal difference on the males and females.

using a well-structured questionnaire who were age and sex matched. This study was conducted on asymptomatic malaria patients and apparently healthy individuals in the Oda Road area of Akure, Ondo State. Two hundred (200) asymptomatic malaria patients, 100 subjects each for males and females were recruited for this study. 5ml of venous blood was collected from each participant into an EDTA bottle which was then used for the determination of full blood count and Malaria. The results showed increase in PCV (p=0.000), RBC (p=0.000), Hb (p=0.000) and no significant difference in WBC (p=0.180), LYM (p=0.841), GRAN (p=0.986), MID (p=0.395), MCV (p=0.111), MCH (p=0.191), MCHC (p=0.791), Plt (p=0.959) when compared between male and female respectively. The study showed increase in packed cell volume, haemoglobin and red blood cells of male compared to females of asymptomatic malaria patients. There were no variations in other haematological parameters studied. The changes in the red cell line may be associated to bone marrow activity difference in the patients and effects of hormonal difference on the males and females.

INTRODUCTION
Malaria is a life-threatening infectious disease of widespread burden. Globally, in 2017, 219 million people were stricken with malaria, which was an increase of 2 million cases as compared to the previous year; of these, approximately 435,000 died due to related complications [1]. Malaria remains a leading communicable disease in the developing countries of the world. It occurs mostly in the tropical and subtropical regions and accounts for considerable morbidity and death. It causes the death of more than one million in Africa every year, and is responsible for fifteen percent (15%) of clinical illnesses in the tropical regions of the continent [2]. Malaria is widespread in tropical and subtropical regions because of the significant amounts of rainfall and consistent high temperatures and high humidity, along with stagnant waters which provide mosquitoes the environment needed for continuous breeding [3,4,5].
It has been documented that asymptomatic malaria parasitaemia (ASMP) serves as reservoir for malaria due to gametocyte transmission [6] and represents, perhaps, one step in the heterogeneous set of the disease pathways [6]. Asymptomatic malaria is prevalent in highly endemic areas of Africa, with only a small percentage of individuals exhibiting clinical symptoms [7]. The clinical consequence of asymptomatic malaria is not fully understood. Some researchers are of the view that asymptomatic parasitaemia is involved in the development of partial immunity and may protect against clinical disease from new infections [7]. The asymptomatic parasitaemics are healthy carriers of malaria parasites and serve as reservoir of infection. The symptomatic people can be treated during their clinical manifestation but the asymptomatics remain unnoticed posing public health danger to the population as long as there is high mosquito vector density to transmit the parasites [8]. So-called "asymptomatic" malaria infections have been recognized for many years, and result from partial immunity (sometimes referred to as premonition, which controls but does not completely eliminate the infection. Although there is no standard definition for "asymptomatic" malaria infections, it is generally accepted to be malarial parasitaemia of any density, in the absence of fever or other acute symptoms, in individuals who have not received recent antimalarial treatment [9]. At any given time, the vast majority of individuals with detectable malaria parasitemia can be categorized as asymptomatic based on this definition, regardless of the level of malaria transmission (Ingrid et al. 2016). This definition includes early detection of rising parasitaemia that has yet to reach the pyrogenic threshold (i.e., the density of parasitized erythrocytes that is sufficient to trigger innate immune responses and fever) [10], infections that are intermittently symptomatic but not severe enough to cause the person to seek health care, and long-standing infections imperfectly controlled by the immune response.
Changes in haematological parameters are likely to be influenced by any disease condition which affects the haemopoetic physiology at any level [11,12,13]. This is likely to happen with an endemic disease such as malaria that affects the host homeostasis at various fronts resulting in a myriad of clinical presentation. Typically, microscopic slide examination of peripheral blood remains the most widely used test and is the gold standard for detecting malaria infection [14].
However, it requires technical expertise and is time-consuming in smear examinations. Moreover, the World Health Organization (WHO) recommends the use of antimalarial drugs based on a definitive demonstration of parasites in the peripheral blood film [15].
Haematological changes are some of the most common complications in malaria and they play a major role in malaria pathology. These changes involve the major cell lines such as red blood cells, leucocytes and thrombocytes [16]. The haematologic picture, however, varies from person to person and largely depends on nutritional status (parameters are severely depleted in malnourished as compared to wellnourished children), intensity of malaria transmission, age, and co-morbidities, such as helminthiasis [17]. Also, Malaria infected patients tend to have significantly lower platelets, WBCs, lymphocytes, eosinophils, RBCs and Hb level, while monocyte and neutrophil counts were significantly higher in comparison to non-malaria infected patients [18]. The most common complication during malaria infection is thrombocytopenia. The most significantly altered parameters are haemoglobin and packed cell volume [19]. To foster the knowledge of haematological parameters, the study was aimed at evaluating the variations of haematological parameters of patients with asymptomatic malaria based on gender in Akure, Ondo State, Nigeria.

Research Design
The study is a cross-sectional study among asymptomatic malaria patients and patients who are apparently healthy individuals. The subjects were selected using a well-structured questionnaire who were age and sex matched.

Study Area
This study was conducted on asymptomatic malaria patients and apparently healthy individuals in the Oda Road area of Akure, Ondo State.

Target Population
Two hundred (200) asymptomatic malaria patients, 100 subjects each for males and females and 100 subjects apparently healthy individuals as the control were recruited for this study.

Blood Collection
5ml of venous blood was collected from each participant into an Ethylene Diamine Tetra-acetic Acid (EDTA) bottle which was then used for the determination of full blood count and Malaria.

Methods of the Test
Screening for Malaria parasite was carried out using Rapid Diagnostic Test. A pink line at the positive and control band indicated a positive reaction whereas only one pink line at the control band indicated negative reaction. No pink line at both positive and negative control bands indicates an invalid result. Thick and thin blood films from each blood specimen were made, allowed to air-dry and stained in 10% Giemsa stain solution for 30 min. The stained smears were rinsed in buffer solution and allowed to airdry. The stained thick films were examined under bright field light microscope for estimation of malaria parasite density while the thin films were examined for species of Plasmodium.

Malaria Parasite Density = (Number of parasite / Number of White blood cell (200)) × 8000
Full Blood Count (FBC): Measurement of haemoglobin, red blood, cells, white blood cells and platelets count were done by using ADVIA® 2120i Haematology system (SIEMENS). The cell count was cross-checked by experienced Medical Laboratory Scientist on duty.

Methods of Data Analysis
The data were presented in tables and as mean ± standard deviation and analyzed using studenttest for parametric data and chi-square for non parametric data by statistical packages for social sciences (SPSS, Version 20.0) and level of significance set at as p≤ 0.05.

RESULTS AND DISCUSSION
The Table 1 showed significant difference in PCV (38.80 ± 4.89%, 31.84 ± 4.86%, p=0.000) RBC (4.70 ± 0.84x10 12 /L, 3.80 ± 0.64 x10 12 /L, p=0.000), HGB (12.97 ± 1.55 g/dL, 10.59 ± 1.63 g/dL, p=0.000), PDW (7.64 ± 1.51 fL, 8.54 ± 1.37 fL, p=0.033) and no significant difference in WBC The study showed increase that was statistically significant in packed cell volume, red blood cell and haemoglobin and no changes in other haematological parameters studied of males compared to the females. The increase of these red blood cells, packed cell volume and haemoglobin could be due to hormonal effects and menstrual loss of blood in females. It could also be related to the malaria having a suppressing effect on the bone marrow. Malaria is associated with anaemia in the patients resulting from dyserythropoiesis and ineffective erythropoiesis but may be more pronounced in females due to these variations observed in this study [20,13]. These mechanisms could be responsible for the decrease in the haemoglobin level observed among the seemingly healthy parasitaemic subjects. A report suggested that persistent asymptomatic malarial infections significantly increase the risk of becoming anaemic [20]. The physicians taking care of the male and females with asymptomatic malaria should take note of these variations in the red cell lines. The red cell indices did not show any variations and the white cell lines.
The changes in the red cell line may be associated to bone marrow activity difference in the patients and effects of hormonal difference on the males and females.

CONCLUSION
The study showed increase in packed cell volume, haemoglobin and red blood cells of male compared to females of asymptomatic malaria patients. There were no variations in other haematological parameters studied. The changes in the red cell line may be associated to bone marrow activity difference in the patients and effects of hormonal difference in the males and females.

CONSENT
Informed consent was obtained from the subjects who participated in the study. The purpose of the study was explained to all participants. Participation in the study was entirely voluntary. Anonymity and confidentiality was ensured and maintained.

ETHICAL APPROVAL
As per international standard or university standard written ethical approval has been collected and preserved by the authors.