- INTRODUCTION AND LITERATURE REVIEW
Malaria is caused by plasmodium, which is transmitted by mosquitoes and the four species of plasmodium cause malaria infection in humans. These are plasmodium falciparum, plasmodium vivax, plasmodium malariae and plasmodium ovale. Plasmodium falciparum (Nchinda, 1998) is responsible for most deaths and most of the severe complications (Singh and Daneshvar, 2013), including cerebral malaria, anemia and renal failure (Aflalo et al 2014). Effect of plasmodium falciparum varies from asymptomatic to multi-organ manifestation, which could lead to death of the victim (Zaki et al, 2013; WHO, 2010).
Malaria accounts for an estimated 2-3million deaths annually and it is also responsible for untold morbidity in approximately 300-500million people annually (Singh and Daneshvar, 2013). Malaria is one of the most common infectious diseases creating an enormous public health problem. The prevalence of malaria infection is more pronounced in the tropics, especially in the sub Saharan Africa than in other parts of the world (Tauil, 2006). Most species of the plasmodium parasites can infect humans. The most serious forms of the disease are caused by plasmodium vivax, plasmodium ovale and plasmodium malariae may cause milder disease in humans that is not generally fatal (Smolensky et al 2015).
Plasmodium infection causes an acute febrile illness which is most notable for its periodic fever paroxysms occurring at either 48 or 72 hour intervals. The severity of the attack depends on the plasmodium species as well as other circumstances such as the state of immunity and the general health and nutritional status of the infected individual. Malaria is a chronic disease which has a tendency to relapse or recrudesce over months or even years (Ham, 2014).
The most common way to obtain malaria is through the natural transmission by mosquitoes. Malaria can also be transmitted via blood transfusions or sharing syringes (Mali et al 2012). Symptoms of malaria includes fever, joint pains, vomiting, anemia caused by haemolysis, hypoglycemia, hemoglobinuria, retinal damage (Beare, 2006) and convulsion. Hypoglycemia literally means low blood sugar. It occurs when blood sugar (glucose concentration) falls below level necessary to properly support the body’s need for energy ans stability throughout its cells. This can occur during severe malaria because the parasite feeds solely on glucose (Fauci et al, 1998). The signs and symptoms of malaria typically begin 8-25 days following infection (Fairhust and wellems, 2010). However, symptoms may occur later in those who have taken antimalarial medications as prevention.
The classic symptom of malaria is cyclical occurrence of sudden coldness followed by rigor and then fever and sweating lasting 4-6 hours, occurring every two days in plasmodium vivax and plasmodium ovale infections, while every three, for plasmodium malariae (Gay et al,2012). Describing a case of malaria as cured by observing the disappearance of parasites from the blood stream can therefore be deceptive (Nwaneri, 2015).
Malaria and other infectious diseases is on the increase in Nigeria. It is therefore important to know the prevalence level of renal involvement in malaria cases to ensure effective managments of the patients as they report to medical centres. Despite the concerted efforts of the World Health Organization (WHO), government and private organizations, the elimination of malaria parasite remains elusive in the tropical region (Akanbi et al, 2014). Because of the development of drug resistant srains of the parasite, the attention on malaria parasite has now been shifted to the prevention of malaria rather than eradication.
Regardless of the soaring malaria incidence in endemic regions, a certain group of individuals seem to have more immunity to malaria than others. This could be accounted by several factors including haemoglobin variants, ABO blood group system and enzyme action, among others (Otajevwo 2013).
1.1.2 PREVALENCE OF MALARIA
Malaria prevalence continues to decline across Sub-Saharan Africa as a result of various interventions. However, the disease still poses a health concern in the region (Deborah et al 2017).
The disease is widespread in the tropical and subtropical regions that exist in a broad band around equator (Caraballo 2014). This includes much of Sub-Saharan Africa, Asia and Latin America (WHO 2014). In 2016, there were 216 million cases of malaria worldwide resulting in an estimated 445,000 to 731,000 deaths (WHO 2017). Approximately 90% of both cases and deaths occurred in Africa (WHO 2014). In Africa, it is estimated to result in loses of US $12 billion a year due to increased health care costs, lost ability to work, and negative effects on tourism (GreenWood et al 2005).
All malaria species can infect without causing symptoms, but because P. falciparum and P. vivax are more prevalent globally, more asymptomatic infections of these two species occur than the other two human malaria species. Asymptomatic infections with P. ovale are rare but have been noted, whereas P. malariae is known to persist in the bloodstream for decades without causing any, or only mild, symptoms (Scuracchio et al 2011). Individuals with P. vivax develop immunity more quickly than with P. falciparum and consequently are able to control parasite densities to a greater degree, but it is not clear whether this translates into a different proportion of infections that are asymptomatic by species. Few comparisons of the prevalence of symptoms among individuals infected with P. falciparum and P. vivax have been conducted in areas where the two species are sympatric, and results are contradictory. Using microscopy to diagnose infections, a larger proportion of P. falciparum infections (37.5%) compared with P. vivax infections (18.5%) in Brazil were asymptomatic (presenting with none of the 13 malarial symptom (L da Silva-Nunes and Ferreira 2007). In comparison, a greater propor- tion of P. vivax infections (97.1%) in the Solomon Islands compared with P. falciparum infections (82.2%) were asymp- tomatic (axillary temperature: <38°C) (Harris et al 2010). Few studies have reported both the number of species-speci c malaria cases and species-speci c symptom rates, and diagnosed all infections by PCR; in Cambodia, 92% of the P. falciparum and 83% of the P. vivax infections were asymptomatic ( Hoyer et al 2012), whereas in Brazil, these proportions were 78 and 93%, respectively (Alves et al 2002). While it appears that the majority of prevalent infections of both species are asymptomatic in cross-sectional surveys, there are no data to suggest that either species is associated with a larger reservoir of asymptomatic infections.
1.1.3 JUSTIFICATION OF THE STUDY
Information on the association of malaria with impairment of renal function in a Nigeria is scanty but very important because malaria is highly endemic in the country. The mortality and morbidity rates of the malaria infection is also high especially in children and pregnant women.
It becomes absolutely necessary that malaria involvement in renal impairment be assessed. This will ensure proper management of malaria infection with its associated complications.
- MAIN OBJECTIVES
- To measure the overall prevalence and intensity of renal impairment in malaria and non-malaria patients by age and sex.
- To determine the relationship between malaria parasitemia and kidney features and functions in malaria patients.
- Study the association between biochemical renal parameters and plasmodium species.
- To determine the relationship between urea and creatinine levels malaria parasite density.