A knowledge-based system for automatic interpretation of an analytical profile of complement factors.

A comprehensive assay to evaluate the complement system includes functional tests of both classical and alternative pathways and immunochemical measurements of C3, C4, B, C1-INA, and C3d. The purpose of this analytical profile is to screen for rare hereditary deficiencies and acquired abnormalities of complement and to define the activation pathway in cases of complement consumptive processes. Based on several years' experience, a routine was established in our laboratory to report the data to the clinician, together with a computer-generated interpretive statement. This routine was formulated into a knowledge base by specifying a series of decision rules for each of the complement disorders. After the rules were tested and updated against some 400 complement profile analyses, reasonable analytical comments were produced by the system. This knowledge-based system for reporting and interpreting complement results offers several advantages: the interpretative work is facilitated and made more reliable; a consistent interpretative comment is generated that is recognized and therefore more meaningful for the clinician; the communication of analytical procedures and policy is enhanced.