This study describes the alterations in the plasma
lipoproteins from nine young Tunisian children with active
visceral Leishmaniasis. The plasma
lipid profile from affected patients was characterized by a marked hypertriglyceridaemia associated with reduced levels of total and
high density lipoprotein (
HDL)-cholesterol and a significant increase in the plasma ratio of unesterified to total
cholesterol. Quantitative determination of plasma
apolipoproteins revealed significantly decreased levels of all measured
apolipoproteins, especially of
apolipoproteins A-I and A-II, with the exception of
apolipoprotein E, the levels of which were markedly increased. Moreover, at least two
isoforms of the
apolipoprotein serum amyloid A (SAA), an
acute phase protein, were detected in all patients' plasma using two-dimensional electrophoresis. Immunochemical evidence was presented that
apolipoproteins E and SAA, although both primarily associated with
apolipoprotein A- (A-I and A-II) as well as with
apolipoprotein B-containing
lipoproteins, could occur as LP-E and LP-SAA subspecies, devoid of
apolipoproteins A and B. However, it should be pointed out that LP-SAA particles were found in HDL2 from only two patients whereas the abnormal LP-E particles were detected in
LDL and HDL2 from all investigated patients. The polydispersity and heterogeneity of patients' HDL3 were assessed by electron microscopy. It was further suggested that the profound changes in the
lipoprotein metabolism of these young patients may be due to the increased hepatic synthesis of
apolipoprotein SAA and/or to their altered immune function during active
visceral Leishmaniasis.