Stein and Myers state that plasma appearance is a simple, inexpensive way of screening specimens for elevated triglycerides: clear serum indicates concentrations of less than 200 mg/dL, turbidity indicates concentrations between 300 and 600 mg/dL, and opacity of serum is associated with concentrations of more than 600 mg/dL Further, the
standing plasma test can indicate need for dilution in triglyceride testing, and can indicate the need for special handling in HDL-cholesterol testing.[1] In my experience, triglycerides are seldom measured in hospitalized patients; the laboratory reporting of lipemic or turbid serum may call the physician's attention to a significant lipid problem.