Patients with low HDL levels during acute Babesia infection also had baseline HDL levels within normal limits in the 2 months before and/or after the infection, which strongly suggests that preexisting HDL deficiency (e.g., due to lecithin-cholesterol acyltransferase deficiency) did not predispose these patients to acute babesiosis. This evidence concerns the gene LCAT and hyperinsulinemic hypoglycemia, familial, 4.