Background: Malaria is a disease caused by a parasite called Plasmodium, which is transmitted by the bite of infected female anopheles mosquito. Plasmodium is a hemiparasite that affects red blood cells leading to their destruction (Hemolysis). In malaria disease, there is an increased bilirubin levels due to hemoglobin breakdown, decreased red blood cell count due to hemolysis and increased erythrocyte sedimentation rate value due to inflammation.

Aim: This study was aimed at evaluating the effects of malaria parasitemia on erythrocyte sedimentation rate (ESR), red blood cell count (RBC), and bilirubin levels in affected adults attending federal university teaching hospital, Owerri, Nigeria.

Method: A total of 90 subjects were recruited for the study. 50 were patients infected with malaria parasitemia, while 40 age - matched healthy subjects served as controls. Seven (7) milliliters of venous blood sample was collected at the antecubital vein aseptically. 2ml was dispensed into ethylenediaminetetraacetic acid containers for RBC estimation, 2ml was dispensed into sodium citrate bottles for ESR determination, while 3ml was dispensed into plain containers for bilirubin estimation. The EDTA, sodium citrate and plain containers were properly labeled with the subjects’ names, sample numbers and date of collection. The blood dispensed into the EDTA, sodium citrate containers, were stored in a refrigerator at -4oC while the serum was stored in a freezer at - 200C prior to use. ESR was analyzed using Westergren method, RBC count using hematology analyzer, and Bilirubin was analyzed using Jendrassik Grof's method. The procedure was carried out at the Federal University Teaching Hospital in Owerri. 

Results: The results of the tests were analyzed using SPSS version. The mean values of ESR (14.51±5.79) mm/hr, total bilirubin (1.15±0.35) mg/dl, conjugated bilirubin (0.19±0.08) mg/dl and unconjugated bilirubin (0.93±0.25) mg/dl were significantly increased in patients with malaria infection when compared to controls (7.7±5.79) mg/dl,(0.68±0.22) mg/dl, (0.15±0.06) mg/dl and (0.53±0.17) mg/dl (p=0.000, p=0.000, p=0.018 and p=0.000). The mean value of RBC (3.99±0.27) x10 12/L was significantly reduced in adult patients with malaria infection when compared to controls (4.56±0.47) x1012/L (p=0.000). There was a significant positive correlation (r=0.38, p=0.007) of total bilirubin with ESR in adult patients with malaria infection. There was a significant negative correlation of total bilirubin with RBC in adult patients with malaria infection (r=-0.65, p=0.000).

Conclusion: This study showed that levels of ESR, RBC count and bilirubin in malaria-infected adults are altered. Therefore, there is need to monitor these parameters in malaria disease. The results of these tests can help to determine the severity of the infection and to identify patients who are at risk for complications or death. Early identification of patients at high risk is essential for ensuring timely and appropriate treatment, which can improve outcomes and reduce mortality..

Malaria is a vector-borne infectious disease caused by the parasite Plasmodium. It is transmitted to humans through the bite of infected female Anopheles mosquitoes (Rabinovich et al., 2017) Malaria is a major global health concern, particularly in tropical and subtropical regions, affecting around 200 million people annually and causing approximately 400,000 deaths each year, mostly among children under the age of five. It remains a significant public health issue in many tropical and subtropical regions, leading to millions of infections and deaths annually. Nigeria, including the city of Owerri, is one of the countries heavily affected by malaria (Cruz et al., 2018). Malaria has been documented for thousands of years, with references dating back to ancient Greek and Roman times. It has had a significant impact on human health and socio-economic development throughout history. Malaria is caused by Plasmodium parasites, with five species being responsible for human malaria. The parasite is transmitted through the bite of infected female Anopheles mosquitoes. Different species of Plasmodium have varying degrees of severity and are prevalent in different regions. Symptoms of malaria typically include high fever, chills, headache, and muscle aches. Severe cases can lead to complications like anemia, organ failure, and cerebral malaria, which can be fatal if not promptly treated. There are several types of Plasmodium parasites that can cause malaria in humans, with Plasmodium falciparum being the most deadly and responsible for the majority of malaria cases and deaths. Other types include Plasmodium vivax, Plasmodium ovale, Plasmodium malaria, and Plasmodium Knowles. Symptoms of malaria usually appear within 7-30 days after the infected mosquito bite (Kumar and Saravu., 2017) Malaria can be diagnosed by examining blood smears under a microscope to identify the Plasmodium parasites or through rapid diagnostic tests that detect specific parasite antigens. Molecular techniques such as PCR (polymerase chain reaction) can also be used for accurate and sensitive diagnosis.  Antimalarial drugs are used for treating malaria, with the choice of medication depending on the species of Plasmodium and the severity of the infection. Prevention strategies include vector control measures (such as insecticide-treated bed nets and indoor residual spraying), chemoprophylaxis for travelers to endemic areas, and research towards the development of effective vaccines (Rabinovich et al., 2017). Malaria has a significant impact on public health, economic development, and healthcare systems worldwide. 

Vaccines are also being developed, with the RTS, S/AS01 vaccine (Mosquirix) being the first and only licensed malaria vaccine so far. Efforts to control and eliminate malaria globally have shown significant progress in recent years, but the disease remains a major public health concern, especially in the areas with limited resources and infrastructure (Chowdhury et al., 2015).

Hematological parameters play a crucial role in the diagnosis, management, and monitoring of malaria infections.

The ESR is a commonly used test to assess inflammation or infection in the body. It measures the rate at which red blood cells settle in a tube over time. Malaria infection can often cause inflammation, leading to an increase in ESR levels. Monitoring ESR can help assess the severity and progression of the disease and the response to treatment. ESR stands for erythrocyte sedimentation rate, which is a blood test used to measure inflammation in the body. The test measures how quickly red blood cells settle at the bottom of a tube over a specific period of time. When there is inflammation in the body, certain proteins called fibrinogen attach to the red blood cells, making them heavier and causing them to settle faster (Kishimoto et al., 2019). ESR is a non-specific test, meaning it does not diagnose a specific condition, but rather indicates the presence of inflammation and helps in monitoring the progression or response to treatment of an underlying condition. The test is typically performed by taking a blood sample from a vein in the arm. The blood is then placed in a specialized tube and allowed to settle for a certain period of time, usually one hour. The distance at which the red blood cells have fallen within that time is measured and reported as the ESR value, measured in millimeters per hour (mm/hr). A higher ESR value indicates increased inflammation in the body (Kishimoto et al., 2019).

ESR can be influenced by various factors, including age, gender, anemia, pregnancy, certain medications, and chronic conditions such as arthritis, infections, or autoimmune diseases. Therefore, ESR results are usually interpreted in combination with other clinical findings and tests.

It is important to note that while ESR is a useful tool in assessing inflammation, it is not specific to any one condition and additional tests may be required to determine the underlying cause of inflammation (Baek et al., 2016).

The RBC count is a measure of the number of red blood cells present in a given volume of blood. Malaria affects red blood cells directly by infecting and destroying them, resulting in a decrease in RBC count. RBC stands for red blood cells. When it comes to malaria, red blood cells play a significant role in the disease cycle.

Once infected female anopheles’ mosquito is inside the body, the Plasmodium invades the liver cells, where it multiplies and matures before infecting the red blood cells (Rabinovich et al., 2017).

Within the red blood cells, the parasites continue to multiply, leading to their rupture and the release of more parasites into the bloodstream. This cycle causes episodes of fever, chills, and flu-like symptoms that are characteristic of malaria. Moreover, malaria affects the shape and functioning of red blood cells. The presence of the parasite causes the infected red blood cells to become sticky and adhere to the walls of blood vessels, leading to blockages and reduced blood flow. This can cause further complications in organs such as the brain, liver, and spleen (Cruz et al., 2018).

In severe cases of malaria, the destruction of red blood cells can result in anemia, a condition where the body lacks enough healthy red blood cells to deliver oxygen to tissues and organs. Treatment for malaria aims to eliminate the parasite from the bloodstream and prevent further infection of the red blood cells. Antimalarial drugs are commonly used to target the parasite at different stages of its life cycle, both inside the liver cells and the red blood cells. Monitoring RBC count can provide insights into the extent of red blood cell damage and the severity of anemia associated with malaria infection (Philipose and Umashankar., 2016).

Bilirubin is a yellow pigment produced during the breakdown of red blood cells. Malaria-induced hemolysis can lead to an increased release of bilirubin into the bloodstream. Elevated levels of bilirubin, specifically indirect bilirubin, can indicate liver and red blood cell dysfunction associated with malaria infection. It is primarily metabolized and excreted by the liver. In the context of malaria, bilirubin levels can be affected due to the destruction of red blood cells by the malaria parasite. When Plasmodium parasites infect red blood cells, they multiply and eventually cause the cells to burst, leading to the release of hemoglobin. The breakdown of hemoglobin results in the production of bilirubin (Abass et al., 2015).

Elevated levels of bilirubin in the bloodstream are observed during malaria infection, particularly in severe cases. This is often indicative of hemolysis, the destruction of red blood cells, which is a characteristic feature of malaria. The liver plays a crucial role in processing the excess bilirubin produced during hemolysis, leading to an increase in bilirubin levels in the blood. Bilirubin levels can be elevated in malaria due to increased red blood cell destruction and subsequent release of hemoglobin. However, it is important to note that bilirubin levels alone are not diagnostic for malaria and should be interpreted along with other clinical signs and laboratory tests (Kumar and Saravu., 2017).

Malaria remains a significant public health concern globally, particularly in developing countries. There are several reasons why it is important to evaluate some hematological parameters and bilirubin levels in malaria infected adults. The clinical manifestations of malaria are variable, and hematological parameters can help to confirm the diagnosis.

Hematological parameters can help to monitor the progress of the disease and assess the effectiveness of treatment. Bilirubin levels are a key indicator of the severity of malaria infection.

This information can help to identify people who are at risk for developing complications from malaria. The results of this study will provide valuable information on the Characteristics of malaria infection in this population and may contribute to improved management of the disease.

In addition, the study will provide a baseline for future research on the topic. The study will help to fill a gap in the literature on some hematological parameters and Bilirubin. Furthermore, malaria has a significant economic impact on Nigeria, as it causes loss of productivity and increased healthcare costs. This study will provide valuable information that can be used to inform policies and programs aimed at reducing the burden of malaria. Evaluating ESR levels can help differentiate malaria from other febrile illnesses and assess disease severity. Malaria infection affects RBCs leading to anemia and other hematological abnormalities. Quantitative analysis of RBC count, hemoglobin concentration, and hematocrit levels can provide insights into disease severity and inform treatment decisions.

Elevated levels of total and indirect bilirubin may serve as markers of malaria infection and provide information about the degree of hemolysis, liver function and disease progression.

Malaria is a major public health concern in Nigeria, with a significant impact on the health and economy of the country. There is limited information on the effects of malaria on hematological parameters and bilirubin in adult patients (Pacheco et al., 2016).

The lack of specific data on the effects of malaria on hematological parameters and bilirubin in adult patients in Nigeria. The need for more research on the effects of malaria in this population. The importance of understanding the effects of malaria in order to inform clinical practice and public health interventions (Baird et al., 2016). The limitations of existing research on this topic, including the lack of standardization of measurement methods and the lack of data from different regions of Nigeria. The potential benefits of the study, such as improving the quality of patient (Kotepi et al., 2015).

Study Area: This research study was carried out at Federal University Teaching Hospital, Owerri, Imo state, from January to March, 2024.

Subjects: The subjects that were recruited for this study included fifty (50) malaria infected patients of both sexes who were attending the medical outpatient clinic of federal university teaching hospital, Owerri. Fifty (50) apparently healthy subjects of both sexes (10 males and 10 females) were also recruited to serve as control. All the subjects were between the ages 20-70 years

Study Design: This study was a cross -sectional research study that involved individuals infected with malaria parasitemia.  Malaria – infected adult patients at the out - patient department were recruited for this study. They were enrolled after providing their informed consents. Questionnaires were administered to obtain their medical history. A capillary blood sample (a drop of blood) was collected through finger prick with needle, a thick smear was made with the drop of blood and used for screening for malaria parasite through rapid field staining technique. Forty non- malaria infected adults were enrolled and used as controls.

Seven millimeters of venous blood were collected from each subject by means of a hypodermic needle and syringe at the antecubital vein aseptically. Two millimeters of blood were dispensed into sodium citrate containers and used to determine the erythrocyte sedimentation rate of each patient using westergren method. Three millimeters of the venous blood were collected aseptically and stored in a plane tube. The tube was centrifuged to obtain the serum, Total and direct Bilirubin levels were determined using Jendrassik Grof's spectrophotometric method. Two millimeters of the blood sample was collected and stored in an EDTA container. RBC count was determined using the EDTA anticoagulated blood in a hematology analyzer which worked on the principle of flow cytometry.

Results from malaria infected adults were compared with non-malaria infected controls

Ethical Approval

The study was approved by the ethics committee of the Federal University Teaching Hospital, Owerri, and subjects who gave their informed consent were enrolled in the study.

Statistical Analysis

The results were analyzed using Software Package for the Social Sciences (SPSS). All values were expressed as mean ± standard deviation. The results were analyzed for statistical significance using the student t-test. Values with P<0>

Table 1: Mean Values of ESR, RBC, Total, Conjugated and Unconjugated Bilirubin in Adult Patients with Malaria Infection and Healthy Controls. 

The mean values of ESR (14.51±5.79) mm/hr, total bilirubin (1.15±0.35)mg/dl, 

conjugated bilirubin (0.19±0.08)mg/dl and unconjugated bilirubin 

(0.93±0.25)mg/dl were significantly increased in adult patients with malaria infection when compared to controls (7.7±5.79)mg/dl, (0.68±0.22)mg/dl, (0.15±0.06)mg/dl and (0.53±0.17)mg/dl(p= 0.000, p = 0.018 and p = 0.000).

The mean value of RBC (3.99±0.27) x1012/L was significantly reduced 

in adult patients with malaria infection when compared to controls (4.56±0.47) 

x1012/L(p=0.000).

Table 2: Mean Values of ESR, RBC, Total Bilirubin, Conjugated Bilirubin and Unconjugated in Adult Male and Female Patients with Malaria Infection.

The mean values of ESR (11.67±4.36) mm/hr, total bilirubin (1.02±0.22) mg/dl, 

and unconjugated bilirubin (0.83±0.16)mg/dl were significantly reduced 

in adult male patients with malaria infection when compared to adult females. (16.40±5.92) mm/hr, (1.23±0.39)mg/dl and (0.99±0.29)mg/dl(p=0.004, p=0.036 and p=0.000).

The mean value of RBC (4.12±0.23) x1012/L was significantly increased 

 in adult male patients with malaria infection when compared to adult 

Females. (3.91±0.27) x1012/L(p=0.006).

Table 3: Correlation of Total Bilirubin with ESR and RBC in Adult Patients with Malaria Infection.

There was a significant positive correlation of total bilirubin 

with ESR in adult Patients with malaria infection (r=0.38, p=0.007), and a significant

negative correlation with RBC in adult Patients with malaria infection (r=-0.65, p=0.000).

Table 4: Correlation of Conjugated Bilirubin with ESR and RBC in Adult Patients with Malaria Infection.

There was a significant positive correlation of conjugated 

bilirubin with ESR (r=0.34, p=0.017) and

a significant negative correlation (r = -0.59, p=0.000) with RBC in adult Patients with malaria infection (r = -0.59, p=0.000).

Table 5: Correlation of Unconjugated Bilirubin with ESR and RBC in Adult Patients with Malaria Infection.

There was a significant positive correlation of conjugated bilirubin with ESR (r=0.43, p=0.002), and a significant negative correlation of conjugated bilirubin with RBC in adult Patients with malaria infection (r=-0.59, p=0.000).

Malaria is a complex and multifactorial disease, with a number of different aspects to consider. The study investigated the evaluation of erythrocyte sedimentation 

rate (ESR), red blood cell count (RBC) 

and bilirubin in malaria infected adults at FUTH in Owerri, Imo State, Nigeria.

It was observed from the result of this study that the values of  ESR and bilirubin was significantly increased in adult patients with malaria infection when compared to controls. The significant increase in the mean values of ESR and bilirubin might be due to the underlying liver damage caused by the malaria parasite. The malaria parasite, Plasmodium, can cause damage to the liver, leading to the release of bilirubin into the bloodstream. This explains why the liver is also responsible for producing proteins that are involved in blood clotting, so when it is damaged, the blood may become more clotting-prone, leading to an increase in the ESR (Hashemi et al., 2015).

The mean value of RBC count was significantly reduced in adult patients with malaria infection when compared to controls. The reduction in RBC count, or anemia, is a common complication of malaria infection. Malaria parasites can cause the destruction of red blood cells, leading to anemia. In addition, the body's immune response to the infection can also damage the red blood cells. In severe cases of malaria, the body may also produce cytokines that further damage the red blood. The results of this study agrees with the study (Dahalan et al., 2019).

According to the study carried out by (Korenromp et al., 2015)was significantly decreased in ESR and bilirubin in adults patients with malaria infection, which is in disagreement with this study.

There was a significant positive correlation of bilirubin and ESR in adult patients with malaria infection. The results of this study agrees with the findings of (Narang et al., 2020) who in their study reported similar findings. This is due to the common underlying cause of both conditions. As mentioned earlier, the malaria parasite can damage the liver, leading to an increase in both bilirubin and ESR. Therefore, when there is an increase in one of these markers, it is likely that the other marker will also increase (Richter et al., 2014). There was a significant negative correlation of bilirubin, ESR and RBC in adult patients with malaria infection. This is due to the treatment of the infection. Treatment for malaria can reduce the level of bilirubin and ESR. In addition, the treatment can also increase the level of RBC, as the body can begin to produce more red blood cells once the infection is under control.

The evaluation of ESR, RBC count, and bilirubin in malaria infected adults at FUTH is a valuable tool for assessing the severity of the infection and the response to treatment. The positive correlation between ESR and bilirubin can indicate the presence of liver damage, while the negative correlation between ESR, bilirubin, and RBC can indicate a successful treatment response. It is important to note that these tests should be interpreted in the context of the individual patient's history and clinical presentation, and they should not be used in isolation to make a diagnosis or treatment decision.

It is important to understand that ESR, RBC count, and bilirubin are only a few of the many tests that can be used to evaluate a patient with malaria. Other tests that may be helpful include a complete blood count (CBC), a blood smear, and liver function tests. In addition, the patient's clinical presentation and history should be considered when interpreting the results of any test. For example, a patient with high bilirubin levels may also have jaundice, which can provide additional information about the severity of the infection.

Recommendation

Based on the available evidence, it is recommended that the evaluation of ESR, RBC count, and bilirubin should be considered in the assessment of adults with malaria infection at FUTH. The results of these tests can help to determine the severity of the infection and to identify patients who are at risk for complications or death. Early identification of patients at high risk is essential for ensuring timely and appropriate treatment, which can improve outcomes and reduce mortality. One thing to keep in mind is that there are other factors that can affect the ESR, RBC count, and bilirubin, such as co-infections, nutritional status, and co-morbidities. Therefore, it is important to consider the patient's overall clinical status when interpreting the results of these tests. It is also important to keep in mind that these tests are not diagnostic of malaria, and a definitive diagnosis should be made based on the patient's clinical presentation and the results of a blood smear examination