Drug interferences with tests performed by a 12-channel autoanalyzer

The information reported in a variety of sources on drug interferences with routine laboratory tests (serum concentrations of sodim, potassium, carbon dioxide, chloride, glucose, BUN, cholesterol, total protein, albumin, total bilirubin, alkaline phosphatase, and SGOT) performed by a 12-channal autoanalyzer was reviewed. A determination was made whether or not the information was based on an evaluation of original articles, if the study was done in vitro or in vivo, what medium was used, if the drug level causing the interference would be encountered in a patient's serum, and if the reported conclusions were clinically significant. The review narrowed considerably the list of drug interactions with laboratory tests performed by 12-channel autoanalyzer methods. Clinically significant interactions were found for (1) aminosalicylic acid and the test for serum glucose; (2) gamma globulins and cholesterol measurement; (3) sulfonamides and paramethadione and the test for albumin; (4) albumin from placental sources and alkaline phosphatas measurement; (5) erythromycin estolate and aminosalicylic acid and the determination of SGOT; and, possibly (5) medications releasing bromide ions and the measurement of serum chloride. The study showed the need to determine the relevancy of drug interactions to the specific methods used in the laboratory of each medical institution.