Sequential analysis of erythrocyte aggregation in P. falciparum malaria with and without ASAQ therapy by optical signal and image analysis

Abstract

The aggregation of erythrocytes is an important mechanism for blood flow through the cardiovascular system. In malaria, this is complicated by infection caused by P. falciparum and is further complicated by the severity of parasitemia. Hence analysis of this micro-mechanism is essential to know the changes in blood not only in diseased conditions but also after artemisinin combination therapy (ASAQ) to alleviate suffering. For analysis purposes, aggregation of erythrocytes was determined by LED laser aggregometer, represented in terms of various parameters related to the changes in laser transmitted intensity. Formed aggregates are further analyzed by imaging and image-processing methods. For this study blood samples from young adults (18 – 40 years old) infected with P. falciparum (n= 80), without any other serious illness, were performed. These samples were selected based on the severity of parasitemia, and were divided into low (LP), medium1 (MP1), medium 2 (MP2), and high (HP) parasitemia. For three days, the selected individuals were treated with artemisinin-based combination therapy ASAQ (Artesunate 4 mg/kg and amodiaquine 10 mg base/ kg once a day). Healthy subjects (n=20) without any history of the disease were selected as a control group. The results, as obtained by various parameters, show a significant elevation of aggregation of erythrocytes (P< 0.05) in P. falciparum malaria with the increase of parasitemia level. There was a decrease in the aggregation after treatment on day four tending towards normal. Thus the current study shows the potential beneficial role of ASAQ on erythrocytes aggregation, which may contribute to reducing the harmful effects on various organs in P. falciparum-infected blood.