Hemolysis, icterus, and lipemia/turbidity (HIL) indices are often measured on serum and plasma, to assess sample quality. This document offers consensus guidelines for the use of automated HIL indices by laboratories, as an aid to annotating potentially affected results as well as the rejection of a specimen or result.
This guideline is intended for use by:
? Manufacturers responsible for establishing HIL indices and alert indices (cutoff values) for use in the automated HIL detection systems in their clinical laboratory instruments
? Laboratory directors, managers, supervisors and medical technologists for establishing or evaluating HIL indices and making judgments about the acceptability of specimens and test results
C56 provides recommendations for:
? Establishing HIL indices to assess sample quality
? Estimating interference effects of hemoglobin, bilirubin, and turbidity to generate alert indices and gray zones
? Reporting (by manufacturers) interference effects of HIL in the reagent instructions for use (IFU)
? Establishing error flags for HIL interference
? Verifying HIL indices in the clinical laboratory
? Managing potential process outcomes of HIL measurements (reporting or rejecting specimens/results due to HIL interference)
This document provides a comprehensive review of the currently available automated HIL detection systems in clinical analyzers. C56 aims to enhance understanding of the mechanisms and interpretations of HIL indices and alert levels in the clinical laboratory. Procedures for investigating, identifying, and characterizing the effects of interfering substances on clinical chemistry test results are not discussed in detail in C56, as these are described in CLSI document EP07.
CLSI C56-A-2012 history
2012CLSI C56-A-2012 Hemolysis, Icterus, and Lipemia/Turbidity Indices as Indicators of Interference in Clinical Laboratory Analysis; Approved Guideline